the last glacial: insights from continuous coring on the new jersey continental shelf

Marine Geology 335 (2013) 78–99

Contents lists available at SciVerse ScienceDirect

Marine Geology

j ourna l homepage: www.e lsev ie r .com/ locate /margeo

The Last Glacial: Insights from continuous coring on the New Jersey continental shelf

Beth A. Christensen a,c,d,⁎, Clark Alexander b, John A. Goff c, R. Jessica Turner d, James A. Austin Jr. c

a Adelphi University, Environmental Studies Program, 1 South Ave, Garden City, NY 11530, United Statesb Skidaway Institute of Oceanography, 10 Ocean Science Circle, Savannah, Georgia 31411, United Statesc Institute for Geophysics, Jackson School of Geosciences, University of Texas at Austin, J.J. Pickle Research Campus, Bldg. 196 (ROC), 10100 Burnet Rd. (R2200), Austin, TX 78758-4445, United Statesd Georgia State University, Department of Geosciences, PO Box 4105, Atlanta, GA 30303, United States

⁎ Corresponding author.E-mail addresses: [email protected] (B.A. Chr

[email protected] (C. Alexander), goff@[email protected] (J.A. Austin).

0025-3227/$ – see front matter © 2012 Elsevier B.V. Allhttp://dx.doi.org/10.1016/j.margeo.2012.10.015

a b s t r a c t
a r t i c l e i n f o
Article history:Received 23 September 2011Received in revised form 31 August 2012Accepted 19 October 2012Available online 3 November 2012

Communicated by J.T. Wells

Keywords:New Jerseycontinental shelfbenthic foraminiferasea levelsedimentsmeltwater pulse 1a

Sedimentation on the Pleistocene New Jersey (NJ) shelf is complex, and results from the interaction of pro-cesses chiefly driven by glacioeustatic change. Erosion, non-deposition, downcutting and infilling combineto produce a complicated set of reflectors and sedimentary units that are best interpreted in the shallow sub-surface with the aid of high resolution seismic reflection profiling. The highly variable lithology on the shelfhas historically been an impediment to significant core recovery in this challenging environment. Coringusing the AHC-800 drilling system provided continuous downcore recovery at three sites on the outershelf. The sites targeted fluvial incisions, channel fill and exposure surfaces associated with glacial lowstands.The exceptional cores were analyzed using an integrated approach. Textural and benthic foraminiferal datawere evaluated to determine the environment of deposition and estimate paleodepth. Carbon dating ofwood and shell material provides the temporal framework for interpretation and K–Ar dating of hornblendecrystals provides insights into the source region of sediments.Our integrated analysis indicates the NJ shelf was a dynamic environment from at least 45 ka. Estimates of sealevel from this study are consistent with other studies from the Pleistocene NJ Margin. The oldest sediments(>36 k.y.) recovered by drilling came from below (Site 3) and above (Site 1) R, a time-transgressive regional un-conformity. Best estimates are for formation of R on the mid shelf, between MIS3b and the MIS3b/a transition,~45 ka, under neritic conditions. Channels were incised during late MIS2, between ~30 and 16 ka. Channel infillwas focused in a narrow time frame, during latest MIS 2 (16–14 ka), shortly after the shoreline began tomigratelandward. Rates of 1–2 cm/yr are consistent with modern fluvial/ estuarine sedimentation rates. Reinvigorationand infilling of the channels around 14 ka is associated with meltwater pulse 1A. We find no evidence at ourstudy area for jökelhlaup deposition associated with the Intra-Allerød cold period ~13 ka. Regional deposition(channel infill and interfluvial regions) was underway by latest MIS2/early MIS1 as sea level transgressed theshelf. The uppermost sediments are of Holocene to Recent age and are routinely and likely rapidly reworked,eroded and mixed by shelf processes. The sediment source during MIS3, as determined by hornblende agedates, was bimodal. Older sediments were derived from the Reading Prong/NJ Highlands and younger sedimentswere sourced from along the Hudson River. Delivery to the study area was through a more southerlypaleo-Hudson position that may have resulted in formation of the outer shelf wedge through deltaic sedimenta-tion during at least MIS 3b–3a.

© 2012 Elsevier B.V. All rights reserved.

1. Introduction

The New Jersey (NJ) shelf (Fig. 1) is a natural laboratory for study-ing the sedimentary response to sea-level change. Thick sequencesof sediment deposited on this passive margin have yielded insightsinto the style and timing of sea-level change, especially for thelate Mesozoic through Cenozoic (e.g., Christensen et al., 1996; Milleret al., 2002, 2005, in press; Katz et al., 2003; Pekar et al., 2003; Goff

istensen),.ig.utexas.edu (J.A. Goff),

rights reserved.

et al., 2005; Gulick et al., 2005; Nordfjord et al., 2005, 2006;Browning et al., 2006, 2008; Mountain et al., 2007; Kominz et al.,2008; Kulpecz et al., 2008; Wright et al., 2009). The extensive historyof study in this region provides the opportunity to evaluatecore-based analyses in the context of more than 75 years of research.However, much existing work is focused on long-term sea-levelchange at scales much longer than Milankovitch, or glacial, scales.Despite the greater understanding of sedimentation and sea-levelfluctuations for the Cretaceous to Cenozoic (e.g., Mountain et al.,2007; Miller et al., in press), the latest Pleistocene response toglacioeustatic change has not received as much attention. Workon the outer NJ shelf in the 1990s (e.g., Milliman et al., 1990; Davieset al., 1992; Duncan, 2001) began to illustrate the complexity of the

http://dx.doi.org/10.1016/j.margeo.2012.10.015

mailto:[email protected]




http://dx.doi.org/10.1016/j.margeo.2012.10.015

http://www.sciencedirect.com/science/journal/00253227

74°W 73°W 72°W

39°N

40°N

41°N

-50

-150

NEWJERSEY

Atlantic City

NYC Long Island

Hudson Shelf Valley

Hudson Canyon

Barnegatinlet

paleo-Hudsonvalley

OuterShelf

Wedge1073

Site 2

Site 3 Site 1

N.J.

Highlands

Hudson RiverHudson Highlands

Fig. 1. Study area and potential sediment source regions. The study area (red) and Sites 1, 2 and 3 (yellow) are shown. The modern position of the Hudson River is to the north, andthe Hudson Canyon extends across the outermost continental shelf/continental slope. Potential source regions for hornblende examined in this study are noted in black. Map afterDuncan, 2001.

79B.A. Christensen et al. / Marine Geology 335 (2013) 78–99

region, with much of its history tied to fluvial erosion at or near theLast Glacial Maximum (LGM).

The lower global sea level at the LGM, estimated to be ~120 mbelow present (e.g., Fairbanks, 1989), caused glacial coastlines offwhat is now New Jersey to shift more than 100 km offshoreand turned the continental shelf from a site of marine depositionto a one dominated by glacial and periglacial processes. RecentCHIRP and other high-resolution studies have mapped complexesof paleo-channels on the shelf (Uchupi et al., 2001; Fulthorpe andAustin, 2004; Nordfjord et al., 2005), indicating a once-active and ex-tensive fluvial system during intervals of subaerial exposure. Thesestudies have shown that the character of the shelf is defined by pe-riods of fluvial incision likely related to Pleistocene glacio-eustaticlowstands of sea-level. Further studies have tested an estuarine infillmodel (Dalrymple et al., 1992; Allen and Posamentier, 1993; Zaitlinet al., 1994), with the latest (Nordfjord et al., 2006) aided by the coringto be further discussed in this paper. Some researchers have linkedfluvialincision/estuarine processes with catastrophic flooding (jøhkulaups),the result of releases of glacial meltwater from the collapse of naturaldams caused by terminal moraines along the Hudson River drainage(e.g., Donnelly et al., 2005). Further complicating the evolution of thelate Pleistocene NJ shelf is the proximity of the Laurentide Ice Sheet tothe study area, which influenced both offshore-directed sediment loadsand regional isostatic balance.

One of the reasons for our limited understanding of the impact ofsea level changes on latest Pleistocene sedimentary deposits is that

the many suspected episodes of erosion and deposition associatedwith glacially-forced change are difficult to resolve with traditionaltools. Although seismic reflection profiles are the foundation for in-terpretation of continental margin stratigraphy, especially the olderCenozoic record (see reviews in Miller et al., 2005; Mountain et al.,2007), it is difficult to resolve high-frequency climate events on gen-erally low-frequency multi-channel seismic reflection profiles. In con-trast, high-resolution CHIRP seismic data is an excellent tool forinvestigation of the shallow subsurface, because it can elucidate thepresence of many fine-scale stratigraphic successions not resolvedin the lower resolution seismic data.

Cores complement CHIRP seismic data by providing critical ground-truthing for interpretations of remotely sensed subsurface imagery.Timing and rates of high-frequency sea-level response can also be de-termined from such samples, once age control is established. However,traditional ocean drilling platforms such as ODP Leg 174A on the NJshelf (e.g., Austin et al., 1998) have been unable to recover continuouscore on the shelf, primarily as a result of unlithified and sand-pronelithologies. In an effort to understand the stratigraphic evolution ofthe NJ margin during the latest Pleistocene, the middle and outershelf was drilled to examine surficial patterns of incision and infill.Three sites (Figs. 1, 2) were sampled using the Drilling, Observationand Sampling of the Earths Continental Crust (DOSECC) active heave-compensated system (AHC-800). The AHC-800 system was deployedthrough the moon pool on the R/V Knorr (Woods Hole OceanographicInstitution), providing a stable drilling platform that compensated for

Line 907

73°30’W 73°00’W 72°30’W

39°00’N

75 m

90 m

105 m

120 m

105 m

39°30’N

40°00’N

Site 2

Site 3Site 1

Legend:

Chirp track lines,R/V Endeavor,2001 and 2002

Drill-sites,R/V Knorr, 2002

Bathymetriccontours

OSW

DSW

Channels

907

909

161

326

2 km

R

Fig. 2. Core locations and CHIRP profiles across the NJ shelf. Red lines on bathymetric map indicate CHIRP profile track lines, in several discrete areas. CHIRP lines discussed in thispaper are labeled in bold (161, 326, 907, and 909). Drill sites 1, 2 and 3 are noted with yellow stars. CHIRP profile 907 (lower right) reveals the subsurface expression of the OSWand DSW. CHIRP lines 161, 907 and 909 extend from the regions of dense coverage in the vicinity of Site 3, where the interpreted buried river channels are located, to the shelf edge.Map after Nordfjord et al., 2005.

80 B.A. Christensen et al. / Marine Geology 335 (2013) 78–99


vertical ship motion and allowed for rotary drilling in up to 2.5 m seas(Nielson et al., 2003). A shipboard dynamic positioning (DP) systempermitted deployment of a taut line and heave tests before enteringbottom with the drill string (Alexander and Austin, 2002). Three holes(4.6 to 13.1 m in length) yielded sequences of sediments from above,through, and below latest Pleistocene seismic unconformities andinterpreted fluvial incisions. The continuity of the coring permittedthe study of the timing and nature of paleo-channel incision on the NJshelf during the last lowstand. We relate our sedimentological, forami-niferal and isotopic dating results to other similar studies, specificallytesting the models developed by Gulick et al. (2005) and Nordfjordet al. (2002, 2005, 2006). We suggest a dynamic and highly variableshelf response to glaciation, with the majority of the activity focusedover relatively short intervals of time.

2. The New Jersey margin setting

2.1. Shelf

The NJ shelf is wide (>150 km) and water depths are generallygreater than 100 m on the outer shelf (Figs. 1 and 2). In contrast tothick, relatively continuous sedimentary sequences of Cretaceousthrough Cenozoic sediments, the surface morphology and uppermoststrata of the NJ shelf are defined more by erosional features thandepositional ones, and are generally interpreted as resulting frompast sea-level changes (e.g., Swift et al., 1972; Knebel et al., 1979;Swift and Field, 1981; Stubblefield et al., 1984; Milliman et al., 1990;Nordfjord et al., 2002; Goff et al., 2005).

The outer shelf wedge (OSW) is a prominent feature of the shallowstratigraphy of the outer NJ shelf (Milliman et al., 1990; Figs. 1 and 2).The OSW is oriented southwest from the Hudson Canyon, and includesthe Hudson Apron, a large, clay-rich feature. Gulick et al. (2005) havealso distinguished a deep shelf wedge (DSW) along portions of the NJshelf edge (visible on Lines 907 and 909, Figs. 2 and 3) that postdatesthe OSW and has more steeply-dipping strata.

The variability of the shallow shelf stratigraphy complicates at-tempts to correlate sequences regionally. Presumed fluvial incisions in-terrupt correlations, and many surficial reflectors pinch out or merge.Carey et al. (2005) have used results from vibracores and previouslydrilled boreholes (e.g., AMCOR, Hathaway et al., 1979), new and olderdominantly 3.5 kHz and 8 kJ mini-sparker and Uniboom data, and pre-vious studies (e.g., Knebel and Spiker, 1977; Knebel et al., 1979;Sheridan et al., 2000) to provide a regional synthesis of shallow shelfstratigraphy. They identify four sequences, two of which correspondto major glacial-interglacial changes-MIS6/5 (sequence I) and MIS 2/1(Sequence IV). These units are generally thick near the shelf edge, butthin or are discontinuous across the shelf. As these units also thicken to-wards the north, there is a possible link to deposition associated withcollapse of a glacially induced peripheral bulge during final (post-LGM)deglaciation (Carey et al., 2005). Deposition associated with MIS 4/3(Sequence II) and MIS 3b/3a (Sequence III) is focused near themid-shelf (mid-shelf sediment wedge; MSW). Sequences III and IVcompose the OSW, and Sequences I, II and III are associated with theDSW and uppermost slope. The development of these features has re-quired high sedimentation rates; their deposition is likely tied to amore southerly position of the ancestral Hudson River in MIS 4/3(Carey et al., 2005).

The results of Carey et al. (2005) are in broad agreement withthose of Lagoe et al. (1997), which relied on vibracores to map thesouthwest portion of the OSW. Lagoe et al. (1997) identified three re-flectors and five stratigraphic units associated with the Wisconsinianglaciation (Fig. 4). They placed their unit S5, which underlies basalOSW reflector R, and S3, in the middle Wisconsinian (late MIS3), andcorrelated them to the inner shelf Sequence I defined by Ashley et al.(1991). However, based on age control presented in Lagoe et al.(1997) and Carey et al. (2005), S5 and S3 are likely equivalent to

sequences II and III. Lagoe et al. (1997) did not sample S4. They interpretS2 and S1 as normal marine deposits associated with deglaciation,shifting from a coastal S2 to a deeper slope S1 (Lagoe et al., 1997), andthus equivalent to Sequence IV of Carey et al. (2005). McHugh et al.(2010) have also evaluated late Pleistocene deposition in this region,but they focused on the Hudson Canyon region, to the north of ourstudy area. Using vibracores and CHIRP profiles, they place the LGM(17 Ka) shoreline near the 120 m isobath.

These studies focus on a view of deposition consistent with that ofearlier workers, such as Milliman et al. (1990), whereby interglacial ma-rine sedimentation is interrupted by sea-level fall and glacial erosion ornon-deposition, with marine sedimentation resuming in subsequent in-terglacial periods. Such a pattern of deposition and erosion results ina discontinuous and spatially complicated stratigraphic section. Gulicket al. (2005) have suggested a different sequence of deposition of theOSW. Their high-resolution CHIRP data provide additional detail on thecharacter of construction of the OSW. Utilizing new and older 14C dates(e.g., Knebel and Spiker, 1977; Lagoe, 1994), Gulick et al. (2005) suggestthat the OSW formed as sea-level was falling, after erosion of thetime-transgressive R horizon during MIS 3. Reduced accommodationspace resulting from lowered sea level during MIS2 led to deposition oftwo prograding, offlapping wedges (Fig. 2). Their model accounts forinverted ages in an OSW core (Core 21; Lagoe, 1994); however, thesedates are not unequivocal. In this paper, we present a detailed analysisof the core at OSW Site 1, which allows us to test their model.

The CHIRP data collected on previous expeditions provide an ex-cellent opportunity to identify interpreted fluvial incision events inthe shallow subsurface. These data (e.g., Goff et al., 2005; Nordfjordet al., 2005, 2006) reveal a series of incised channels in the northernpart of the study area (Fig. 1). Nordfjord et al. (2005) have deter-mined that main trunk channels had box-like cross-sections, withv-shaped tributary channels. They infer rapid development andinfilling, with downcutting at the time of the LGM, and infilling andultimately drowning associated with the post-LGM transgression.Correlation of initial shipboard analysis of Site 3 sediments (describedmore fully below) to the seismic geomorphologic interpretation ofthe imaging and a co-located synthetic seismogram, permitted themto generate a model of estuarine infilling (Nordfjord et al., 2006)that can be tested with the paleoenvironmental results from the inte-grated textural and foraminiferal study presented in this paper.

Glacially induced isostatic adjustment is an important element ofany discussion of Pleistocene sedimentation. Dillon and Oldale (1978)have identified a hinge line extending southeast from Barnegat Inlet,NJ (Fig. 1). Using lower resolution seismic reflection profiles, they deter-mined areas south of the shoreline (Site 2) are ~horizontal, indicatinglittle disturbance, and areas to the north of the hinge line dip to thenorth-northeast, flattening out again towards Long Island. Dillon andOldale (1978) have postulated that the boundary faults of one of themany underlying rift blocks or fracture zones were reactivated duringglaciation. Sites 1 and 3 are at or just north of the location of theirhinge zone. Carey et al. (2005) suggest the interpreted channels horizon(Fig. 4) at Sites 1 and 3 are ~20 m lower than sediments of the sameage at locations farther south. The slightly deeper glacial water depthscould have provided essential accommodation space for deposition atthe deep shelf wedge.

2.2. New Jersey Margin benthic foraminifera

The long history of research of the NJ margin has resulted in nu-merous studies of foraminiferal distribution and environmental affin-ity, with sometimes conflicting results. Variability in local conditionsor even methods of analysis is often the cause of these conflicts.Also, downcore studies cannot distinguish between living and deadspecimens, and have the potential for vastly different assemblagesdue to transport, selective preservation, and relict sedimentation.

Gravel(%)

50 101000

Sand(%)

1000

Silt(%)

1000

Clay(%)

8000

No. BenthicForaminifera

1000

Elphidium spp.(%)

0

A. beccarii(%)

300

Cib. spp.(%)

300

Deeper WaterBenthics (%)

500

0

100

200

300

400

K/Ar Age(Ma)

Lithologic Units

0

100

200

300

400

500

Dep

th (

cm)

A

B

C

D

930 ± 20

930 ± 20

850 ± 20

a b c d

Site 1abc

d

0

5 m

10

0 50 m

R

A

D

C

B

10.8 Ka

35.9 Ka

43.7 Ka

Transparent

NW SE

82B.A

.Christensenet

al./Marine

Geology

335(2013)

78–99


Katz et al. (2003) have developed a comprehensive tabulation ofprevious studies of the NJ margin species in the scientific literature.Their compilation provides the basis for our benthic foraminiferalpaleoenvironmental indicators (Table 1). Although Elphidium speciesare found over a wide depth range, when found in combination withAmmonia beccarii and Trochamina inflata, abundant Elphidium speciesindicate nearshore, saline (i.e., estuarine) environments (Poag, 1981).Elphidium species dominate the inner continental shelf environment(Parker, 1948; Poag et al., 1980; Poag, 1981; Culver and Snedden, 1996).The middle shelf is associated with an assemblage of Angulogenerinaangulosa, Quinqueloculina, and Triloculina species (Loeblich and Tappan,1953; Gevirtz et al., 1971; Matoba and Fukasawa, 1992; and Lagoe et al.,1997). Middle-to outer-shelf foraminifera include the assemblage ofCassidulina spp. and Bulimina marginata (Poag, 1981). The outer shelf isdominated by an assemblage of Sphaeroidina bulloides and Cibicidoidesspp., with Cibicidoides spp. associated with the shelf edge (Poag, 1981;Matoba and Fukasawa, 1992). These are not the only species living inthese environments and at these depths, but they comprise the dominantand distinctive assemblages for the designated water depths.

Buck et al. (1999) have used benthic foraminifera to evaluate thepaleoenvironment of a filled fluvial/estuarine channel and the region-al reflector “R” in vibracores from the mid-and outer-shelf wedges,focused west-southwest of Site 3. They identified four assemblages:1) Group A, dominated by Cibicides lobatulus and interpreted as amodern, mid-outer-shelf environment; 2) Group B, composed ofQuinqueloculina spp. coupled with shell hash, and interpreted as amiddle-shelf environment; 3) Group C, dominated by E. excavatumand interpreted as inner-middle shelf environment; and 4) Group D,a marginal marine environment dominated by A. becarrii, althoughcontaining a significant number of Cibicides refulgens. Below the ve-neer of modern sands (Group A), they identified a series of shifts inpaleoenvironment, between mostly groups B and C, reflecting environ-mental shifts resulting from an interpreted regional transgression pro-ceeding from the SE to NW. The Buck et al. (1999) analysis of the infill(~12.5 ka) of a seismically observed channel incision (~45 ka) revealsfrequent variations between marginal-marine and middle-shelf envi-ronments, but we will show that the timing is different for our study.Our distribution of species, and thus assemblages, also differs fromthat of Buck et al. (1999). For example, our study does not contain a sin-gle example of Group B (Quinqueloculina spp. Dominant, with lowabundances of Elphidium spp.) or Group D (A. beccarii dominant, withsecondary abundance of Elphidium spp.). But this is not surprising,considering the highly variable and dynamic nature of the NJ shelfenvironment.

3. Methods

Cores were collected from the R/V Knorr equipped with the DOSECCAHC-800 heave-compensated drilling rig during 2002. Cores from threesites from the NJ shelf (identified in Figs. 1 and 2 as Sites 1–3) ranged inlength from 4.6 to 13.1 m. Three types of tools were employed: anon-rotating hydraulic piston corer (HPC), non-rotating extendednose push corer (XN), and a rotating diamond-bit corer (Alexanderand Austin, 2002). Maximum core quality and recovery (80–90%)were achieved with the HPC using half stroke (1.5-m) penetration(Alexander and Austin, 2002). Unlike earlier shelf studies, which uti-lized vibracores and piston cores, core recovery was high using theAHC-800 (Site 1A/HPC, 89.9%, 4.6 m recovered over 5.1 m penetration;

Fig. 3. CHIRP profile 909 and lithostratigraphic, textural and foraminiferal results for Site 1. Severtical line indicates the core location and approximate depth of penetration on the crossing C1A-1-2, 90–120 cm; b = Unit C, 1A-1-2, 120–150 cm; c = Unit C, 1A-2-1, 60–90; d = Unit D,Depths of hornblende analyses and ages of hornblende crystals (see Table 5) are shown in thand vertical exaggeration is ~12.5×. Note that reflector R at this site is located below the targe

Site B, C XN, 45–48%; Site 2HPC, 85 to 100% recovery; Site 3 43.9%, 0.9 mrecovered over upper 2 m penetration, and 100% in the lower 6.2 m).

Coreswere collected in plastic liners; cut into 1.5 m lengths on deck;logged with a multi-sensor track logger; and split, photographed anddescribed in the laboratory. Samples were taken shipboard for porositycalibration and AMS C-14 analyses. The 62-mm diameter cores werestored in D-tubes and archived at the Lamont-Doherty EarthObservato-ry (LDEO) ODP core repository and integrated into the ODP database.They have since been sub-sampled extensively for detailed analysis oftime stratigraphy, sediment texture, and depositional environment.The cores were also imaged using the LDEO X-ray machine to revealsedimentary structure.

A total of 303 samples were analyzed for detailed textural analysisat 0.25-phi intervals, using sieves for the fraction coarser than 63 μmand a Sedigraph 5100 for the fraction finer than 63 μm (Table 2).Sixty-three samples for detailed age control were analyzed for 14Cage using Accelerator Mass Spectrometry (AMS) techniques at theWHOI NOSAMS laboratory and at the University of Georgia Centerfor Applied Isotope Studies (Table 3). Ages were calibrated usingCALIB 6.0 (Stuiver et al., 2005) with a marine reservoir correction of733 year and DR of 333+78 years. These materials were collectedon board the R/V Knorr or during a later trip to the ODP repositoryto collect additional dateable materials, aided by examination of the~120 X-radiographs produced from the cores.

Eighty samples were dried, weighed, and washed with de-ionizedwater through a 63 μm sieve for foraminiferal analysis (Table 4). The>63 μm fraction was dried at ~60 °C and weighed. Samples wereseparated in a 150 μm sieve and all individuals were picked. Thecoarse fraction was picked for benthic foraminiferal species, sortedby species and counted. Due to the high incidence of abrasion andbreaking of specimens, Elphidium and Cibicides species were sortedby genera rather than species. There were usually not enough pristineforaminifera to generate a statistically valid special analysis (300 areneeded), and so both abraded/broken and pristine foraminiferawere used in this study. Even so, the total number of individualswas often below 300. In the rare instances when foraminifera wereabundant, the sample was split to achieve an aliquot of ~300specimens.

Paleo-water depths were determined by comparison to modernassemblages (Table 1), based on multiple studies (Parker, 1948;Loeblich and Tappan, 1953; Gevirtz et al., 1971; Poag et al., 1980;Poag, 1981; Matoba and Fukasawa, 1992; Culver and Snedden,1996; Lagoe et al., 1997, that were compiled and cited in Katz etal., 2003). The low benthic foraminiferal abundances meant thedata were used to provide a guide to depositional environment,rather than absolute water depths. We assumed no isostatic adjust-ment and did not perform a backstripping analysis to remove com-paction due to the very shallow nature of the cored holes. Ourassumption is justified on the basis of estimates by Wright et al.(2009) of limited subsidence (~5 m at MIS 4 and ~0 at MIS 3) atthe interpreted paleoshorelines in this region, although they noteup to +15 m error is possible. However, we recognize the potentialfor glaciostatic change, especially since the hinge line is located soclose to the study area, and provide alternate interpretations inthe discussion below.

Hornblendes were picked from six samples at Sites 1 and 3 afterseparation of heavy minerals. Ages from these hornblendes were de-termined using K–Ar in the laboratory of Marion Wampler at Georgia

e Fig. 4 for key to lithostratigraphy. Radiocarbon ages (see Table 3) are shown in red. RedHIRP profile. Photographic insets illustrate significant lithologies and contacts (a= Unit B,1A-2-2, 128–150) and their relative stratigraphic positions are shown on the CHIRP line.e lower panel. Water depth at the coring site is 129 m, depth to base of core is 6 mbsf,t depth and hence was not sampled.

100

200

300

400

A

B

C

D

R

OSW: upper transparent unit

OSW: Lower Layered unit

Deep Shelf Wedge

Site 3 & Buck et al., 1999 piston core

Site 2

Site 1

OS Veneer

Lagoe et al., 1997stratigraphy

S

S5

S4

S3

S2S1

0

100

200

300

400

500

600

700

800

Dep

th (

cm)

A

B

B

C

D

E

F

C

R

0

100

200

300

400

500

600

800

900

1000

1100

1200

1300

1400

A

B

B

C

D

Site 1Site 3 Site 2

700

C

Incision

Holocene veneer

Outer ShelfWedge

Outer Shelf

Wedge

Channel InfillChannel

Infill

Incision

Change inChannel Morphology

Key to Lithologysands with shell hash

sands

interbedded sand/mud

chaotic mud

mud

Fig. 4. Stratigraphic relationships of sites 1, 2 and 3. The lithostratigraphy and depositional patterns are shown below a cartoon of NJ mid-to outer shelf deposition including theapproximate locations of cores (after Lagoe et al., 1997; Buck et al., 1999). Although coring yielded nearly continuous recovery, a few gaps are present at shelf Sites 2 and 3 withinsandy Unit B. OSW Site 1 was continuously cored, with no apparent gaps. Key to the lithology applies to Figs. 3, 4, 6 and 7.


Institute of Technology (Table 5). Approximately 3–5 mg were re-moved from the >0.125 mm size fraction, rinsed in an acid bathand then crushed under ethanol. Samples were digested for both K

and Ar determinations, which were performed on a Perkin ElmerAAS 3100 (K) and AEI MS-10 (Ar). See Turner (2005) for additionalmethods.

Table 1Benthic foraminiferal paleoenvironment indicators. Compilation based on Katz et al. (2003).

Environment Indicator species Comments References

Estuarine A. beccariiElphidium spp.T. inflata

Nearshore-salineNearshore (with A. beccarii)

Poag, 1981

Inner shelf(b~20 m w.d.)

Dominant Elphidium spp. Poag, 1981; Poag et al., 1980; Culver and Snedden, 1996; Parker, 1948

Middle shelf(30–90 m w.d.)

A. angulosaQuinqueloculina spp.Triloculina spp.

Lagoe et al., 1997; Gevirtz et al., 1971; Loeblich and Tappan, 1953;Matoba and Fukasawa, 1992

Middle to outer shelf(60–180 m w.d.)

Cassidulina spp.B. marginata

Poag, 1981

Outer shelf(>100 m w.d.)

S. bulloidesCibicidoides spp.(Shelf edge)

Matoba and Fukasawa, 1992; Poag, 1981


4. Textural and foraminiferal results and depositional environment

4.1. Site 1

Site 1 (39.2391° N, 72.6863°W; 127 m w.d.; Figs. 2–4) penetrated6.7 m into the OSW and terminated above R, a regionally prominentreflector. Because of the stratigraphic uncertainty related to coringHoles B and C (6.7 m to 4.6 m), we have focused our research onthe upper, 4.6 m long Site 1, Hole A, recovered using HPC.

4.1.1. Unit 1D: 461 (Base) to 352 cmbsf (1A-2-2, 147 cm–37 cm)Basal Unit D is dominated by fine-grained sediments, indicating a

low energy depositional system (Figs. 3 and 4). The lowermost mudscontain broken, reduced shell material or wood (Figs. 3 and 4) indi-cating a higher energy interval near the base. The basal shell layer isdated at 43.7+0.21 ka (MIS 3b/3a; Table 3; and Fig. 5). The mudsfrom 461 to 405 cmbsf are stiff but not laminated, and are overlainby more chaotic muds from 405 to 353 cmbsf.

We interpret that Unit 1D consists of an estuarine environment atthe base, deepening upward to an inner shelf environment. The lower-most foraminiferal sample contains a fairly high number of specimens(123 individuals, Fig. 3 and Table 4), dominated by Elphidium spp.;A. beccarii is also present (8.1%), along with microscopic iron nodulesand iron-staining of the Elphidium spp. (see photographic inset d, Fig. 3).Iron-staining is commonly associated with estuarine paleoenvironments,but also with a subaerial exposure surface. The absence of the third estu-arine co-indicator, Trochaminina spp., and presence of Cibicidoides spp.(middle-outer shelf) and Quinqueloculina spp. (middle shelf), all suggestsome mixing and/or deposition of reworked sediments. Upper Unit 1D(361 cmbsf, 1A-2-2, 45–47 cm; 352.5 cmbsf, 1A-2-2, 39–36 cm) is dom-inated by Elphidium spp. (97%) but contains no A. beccarii, which suggestsa shallow marine (inner shelf-estuarine) environment.

This interval on the crossing CHIRP profile has zones of transpar-ency (Fig. 3), and further suggests an erosional incision into underly-ing sediments and disturbance of preexisting reflectors. The erosionalboundary between laminated strata below and transparent sedimentwithin the interpreted incision occurs regionally and has beeninterpreted by Goff and Austin (2009) as iceberg scour duringHeinrich event 3 (H3). The H3 age (~30 ka) is younger than radiocar-bon ages frommaterial deposited after the erosion event. However, asnoted in Gulick et al. (2005), Goff and Austin (2009), and our ownanalysis at Site 3 (below), reworking can result in inverted radiocar-bon ages. The cap of chaotic muds within Unit D may be relatedto erosion and redeposition consistent with a shallow marine deposi-tional environment.

4.1.2. Unit 1C: 352–165 cmbsf (1A-2-2, 37 cm to 1A-1-2, 120 cm)Unit 1C is characterized by sand concentrations ranging from b5%

to >10% within an overall clay matrix (>50%, Figs. 3 and 4; Table 2).These muds contain planar laminations throughout, except for tilted

laminations from 315 to 231 cmbsf (see the photographic inset c inFig. 3). A decrease in silt and increase in clay occurs from ~250 to190 cmbsf (photographic inset b Fig. 3), suggesting an overall waningof depositional energy.

There is no stratigraphic control for this interval. The number offoraminifera is zero or close to zero (Fig. 3; Table 4). The few speci-mens in the lowermost sample (352 cmbsf) are iron-stained; an estu-arine or inner shelf environment is a likely interpretation. Mudsampled at 219.5 cmbsf contains a few foraminifera (Table 4) thatalso suggest an inner shelf environment.

4.1.3. Unit 1B: 165 cmbf to 64 cmbsf (1A-1-2, 120–19.5 cm)This unit is characterized by inter-bedded sands and muds, with

higher percentages of sand than the underlying units (see photographicinset a in Fig. 3) persisting over tens of centimeters (e.g., ~100–75 cmbsf, Figs. 3 and 4; Table 2). The change between units 1C and 1B(Fig. 4), frommuds with thin sand and silt laminations below to thickerlayers of sand and mud above, suggests an increase in energy. A radio-carbon age of 35.9+0.12 ka (MIS 3) was recovered from material at129.5 cmbsf (Table 3) and may be related to reworking associatedwith possible ice scouring at Heinrich event 3, ~30 cal ka (Goff andAustin, 2009). Two intervals near the bottom of this unit (161 and150 cmbsf) contain abundant foraminifera (503 and 353 individuals,respectively) (Fig. 3; Table 4). The assemblages are dominated byElphidium spp. and, like Unit 1D, include estuarine (A. beccarri, 1.4%),middle shelf (Quinqueloculina spp. 5.7%) andmiddle-outer shelf (abrad-ed Cibidicoides spp., 10.1%) indicators (Table 4). Bulimina marginata andother Bulimina spp. also increase in abundance (Table 4), which sug-gests deeper water depositional conditions. This is a mixed estuarineand deeper water assemblage, and based on the radiocarbon age, maybe reworked.

4.1.4. Unit 1A: 64 cmbsf to top (1A-1-2, 19.5 cm to 1A-1-1, 0 cm)Unit 1A is characterized by high abundances of sand (Figs. 3 and 4).

Age control is provided by a radiocarbon date of 10.8+.17 ka (onwood) at 40 cmbsf, placing it within MIS 1 and after the YoungerDryas Event (12,650–11,500 yr B.P., Björck et al., 1998). Abundant fora-minifera are dominated by a diverse assemblage of -middle-outer shelfforaminifera, consistent with the modern water depth of 129 m (Fig. 3;Table 4).

4.1.5. Depositional history of Site 1The sediments and foraminifera reflect the position of Site 1 within

the OSW. FollowingWright et al. (2009) which assumes little or no iso-static adjustment, sea level during MIS 3a (post-R) was in the range of~40 m lower than today (Fig. 5); modern water depths are ~127 m,so MIS3a water depths are predicted to be much deeper (middle toouter shelf) than the foraminifera indicate (estuarine to inner shelf)for Units 1D, 1C and 1B. A peripheral bulge would have relaxed byMIS 3, making the predicted depths even greater, so isostatic

Table 2Textural data for Sites 1, 2, and 3.

Site/hole/core/section

Depth insection(cm)

Cumulativedepth(cm)

Gravel(%)

Sand(%)

Silt(%)

Clay(%)

Mean size(phi)

1-A-1-1 1 1 1.88 87.41 5.11 7.48 2.541-A-1-1 11 11 2.79 85.20 5.98 8.82 2.801-A-1-1 21 21 2.18 79.63 8.52 11.85 3.081-A-1-1 31 31 2.53 85.19 6.21 8.60 2.821-A-1-1 40 401-A-1-1 41 41 3.03 76.26 5.85 14.86 3.191-A-1-2 1 45.5 0.83 67.81 9.55 21.80 4.121-A-1-2 11 55.5 1.44 74.20 7.67 16.69 3.441-A-1-2 21 65.5 0.09 13.01 22.52 64.38 8.311-A-1-2 31 75.5 1.02 71.28 9.97 17.74 3.791-A-1-2 41 85.5 0.66 51.38 13.55 34.42 5.421-A-1-2 51 95.5 0.20 58.74 9.86 31.20 4.971-A-1-2 61 105.5 0.00 0.48 18.43 81.09 10.001-A-1-2 71 115.5 0.15 75.98 6.38 17.49 3.451-A-1-2 81 125.5 0.00 7.19 15.67 77.14 9.301-A-1-2 91 135.5 0.56 17.05 22.36 60.04 8.101-A-1-2 101 145.5 0.00 5.01 31.44 63.55 8.741-A-1-2 111 155.5 0.00 11.32 34.64 54.04 8.121-A-1-2 121 165.5 0.00 1.75 16.97 81.28 9.971-A-1-2 131 175.5 0.63 10.40 26.10 62.88 8.631-A-1-2 141 185.5 0.00 3.90 19.70 76.40 9.651-A-1-2 146 190.5 0.00 0.75 14.88 84.37 10.241-A-2-1 1 206 2.20 6.85 15.20 75.75 9.191-A-2-1 11 216 0.00 12.58 19.22 68.20 8.991-A-2-1 21 226 0.00 1.16 27.20 71.65 9.371-A-2-1 31 236 0.00 5.03 32.27 62.70 8.721-A-2-1 41 246 0.00 10.76 34.56 54.67 8.121-A-2-1 51 256 0.00 3.41 43.53 53.07 8.221-A-2-1 61 266 0.00 10.91 25.72 63.37 8.841-A-2-1 71 276 0.00 2.28 32.74 64.99 9.031-A-2-1 81 286 0.00 6.46 29.23 64.31 8.861-A-2-1 91 296 0.00 14.04 32.67 53.29 8.041-A-2-2 1 316 0.00 3.02 36.27 60.71 8.711-A-2-2 11 326 0.00 23.22 15.51 61.27 8.491-A-2-2 21 336 0.00 6.85 37.07 56.08 8.341-A-2-2 31 346 0.00 4.88 36.29 58.84 8.551-A-2-2 41 356 0.00 1.37 33.31 65.32 9.111-A-2-2 51 366 0.00 0.31 36.87 62.81 8.881-A-2-2 61 376 0.04 3.99 29.75 66.21 8.801-A-2-2 71 386 0.00 2.38 28.04 69.58 9.211-A-2-2 81 396 0.00 1.02 35.07 63.91 8.991-A-2-2 91 406 0.00 3.04 32.77 64.19 8.891-A-2-2 101 416 0.00 1.79 34.44 63.77 8.981-A-2-2 111 426 0.00 0.83 28.68 70.49 9.281-A-2-2 121 436 0.00 0.69 37.19 62.12 8.891-A-2-2 131 446 2.61 6.31 38.46 52.61 8.111-A-2-2 141 456 0.00 1.56 30.63 67.81 9.292-C-1-1 1 12 4.63 94.12 0.54 0.71 0.972-C-1-1 11 22 44.47 54.85 0.50 0.18 0.022-C-1-1 22 33 1.45 97.59 0.56 0.40 1.232-C-1-1 31 42 0.00 99.17 0.33 0.50 1.412-C-1-1 41 52 1.82 97.26 0.56 0.36 1.322-C-1-1 51 62 0.15 99.20 0.15 0.49 1.262-C-1-1 61 72 0.22 98.72 0.74 0.32 1.292-C-1-1 71 82 0.45 98.63 0.62 0.31 1.262-C-1-1 81 92 0.10 98.61 0.89 0.40 1.282-C-1-1 91 102 0.13 99.03 0.43 0.41 1.272-H-1-1 1 214 0.05 95.16 1.26 3.54 1.302-H-1-1 11 224 44.21 51.62 2.12 2.05 0.062-H-1-1 21 234 1.06 96.24 0.99 1.71 1.352-H-1-1 31 244 0.00 97.27 0.54 2.19 1.402-H-1-1 41 254 0.00 97.54 0.69 1.77 1.302-H-1-1 51 264 0.00 97.17 0.55 2.28 1.302-H-1-1 61 274 0.00 98.55 0.37 1.08 1.302-H-1-1 71 284 0.00 98.60 0.79 0.61 1.302-H-1-1 81 294 0.14 98.49 0.86 0.51 1.302-H-1-1 91 304 0.13 98.72 0.78 0.36 1.302-H-1-1 101 314 0.00 99.00 0.71 0.29 1.102-H-1-2 1 324 0.00 99.03 0.48 0.49 1.302-H-1-2 11 334 0.00 99.05 0.16 0.79 1.302-H-1-2 21 344 0.00 98.99 0.12 0.90 1.402-H-1-2 31 354 0.20 98.88 0.26 0.66 1.302-H-1-2 41 364 0.00 99.32 0.01 0.66 1.30

Table 2 (continued)


Depth insection(cm)

Cumulativedepth(cm)

Gravel(%)

Sand(%)

Silt(%)

Clay(%)

Mean size(phi)

2-H-1-2 51 374 0.00 99.48 0.21 0.31 1.252-H-1-2 61 384 0.03 99.97 0.00 0.00 1.212-H-1-2 71 394 0.06 99.47 0.29 0.18 1.272-H-1-2 81 404 0.06 99.94 0.00 0.00 1.312-H-1-2 91 414 0.10 99.30 0.30 0.30 1.292-H-1-2 101 424 0.03 99.55 0.21 0.21 1.332-H-1-2 111 434 1.49 98.10 0.21 0.21 1.272-H-1-2 121 444 1.51 97.87 0.00 0.00 1.302-H-1-2 131 454 0.18 99.29 0.00 0.00 1.282-H-1-2 141 464 0.51 98.82 0.49 0.19 1.372-I-1-1 5 2.59 77.94 4.12 15.34 3.732-I-1-1 11 453 0.35 93.34 1.97 4.34 1.492-I-1-1 21 463 2.59 91.90 2.38 3.13 1.332-I-1-1 31 473 3.92 90.54 2.68 2.86 1.222-I-1-1 41 483 25.04 71.90 1.37 1.69 0.402-I-1-1 51 493 31.82 65.33 1.06 1.79 -0.022-I-1-2 2 501 12.30 83.60 2.64 1.46 0.382-I-1-2 11 510 5.16 90.69 1.32 2.83 1.162-I-1-2 21 520 11.84 85.24 1.97 0.94 0.922-I-1-2 31 530 5.40 91.02 1.63 1.95 1.172-I-1-2 41 540 11.23 85.84 1.90 1.03 0.972-I-1-2 51 550 33.91 63.88 0.84 1.37 0.292-I-1-2 61 560 5.16 92.65 0.22 1.97 1.152-I-1-2 71 570 9.47 88.26 0.56 1.71 1.012-I-1-2 81 580 4.49 92.16 1.37 1.97 1.172-I-1-2 91 590 4.13 92.36 1.54 1.97 1.142-I-1-2 101 600 2.01 95.65 0.79 1.54 1.112-I-1-2 111 610 1.34 95.99 0.96 1.71 1.172-I-1-2 121 620 8.33 89.24 0.97 1.46 1.072-I-1-2 131 630 15.99 82.33 0.76 0.92 0.922-I-1-2 141 640 21.81 76.42 0.57 1.20 0.852-J-1-2 11 653 0.82 56.65 17.38 25.15 5.532-J-1-2 21 663 0.66 66.08 12.54 20.72 4.942-J-1-2 31 673 0.00 65.17 15.57 19.26 4.972-J-1-2 41 683 0.01 83.87 5.65 10.47 3.832-J-1-2 51 693 0.00 74.99 8.44 16.57 4.602-J-1-2 61 703 0.00 64.37 15.81 19.81 5.112-J-1-2 71 713 0.00 54.03 20.74 25.23 5.752-J-1-2 81 723 0.00 46.31 24.96 28.73 6.072-J-1-2 90 732 0.00 78.02 8.20 13.78 4.292-J-1-2 92.5 734.5 0.00 35.43 30.85 33.72 6.532-J-1-2 96 738 0.00 10.62 45.92 43.47 7.732-J-1-2 101 743 0.17 97.16 1.40 1.27 2.182-J-1-2 111 753 36.34 62.11 0.85 0.69 1.022-J-1-2 121 763 0.24 96.79 1.55 1.41 2.382-J-1-2 131 773 0.19 98.66 0.79 0.37 1.882-J-1-2 141 783 0.46 95.91 1.80 1.83 2.062-J-2-1 11 803 4.46 94.62 0.42 0.50 1.582-J-2-1 20 812 10.48 88.15 0.65 0.72 1.302-J-2-1 30 822 7.47 91.07 0.89 0.57 1.182-J-2-1 41 833 0.00 56.08 15.06 28.86 5.922-J-2-1 51 843 0.00 79.51 9.69 10.80 4.232-J-2-1 61 853 0.00 63.60 16.36 20.04 5.282-J-2-1 71 863 0.00 61.04 15.21 23.75 5.482-J-2-1 81 873 0.00 44.75 24.45 30.80 6.242-J-2-1 91 883 0.00 65.61 16.67 17.72 5.012-J-2-1 101 893 0.00 33.95 28.16 37.89 6.912-J-3-1 2 916 0.00 60.75 18.43 20.82 5.312-J-3-1 11 925 0.00 29.27 34.25 36.48 6.862-J-3-1 21 935 0.00 86.17 5.31 8.52 4.042-J-3-1 31 945 0.00 38.58 27.25 34.17 6.552-J-3-1 41 955 0.17 49.82 24.56 25.44 5.792-J-3-1 51 965 0.00 41.70 58.30 30.89 6.322-J-3-1 61 975 0.00 43.88 24.38 31.74 6.342-J-3-1 71 985 0.00 64.09 20.85 15.06 4.892-J-3-1 81 995 0.00 43.56 30.21 26.23 5.992-J-3-1 91 1005 0.00 49.58 25.93 24.48 5.812-J-3-1 101 1015 0.00 75.09 12.24 12.68 4.412-J-3-1 111 1025 0.00 51.14 23.23 25.63 5.822-J-3-1 121 1035 0.20 72.33 12.53 14.94 4.512-J-3-1 123 1037 3.26 89.42 4.27 3.04 1.902-J-3-1 131 1045 0.18 85.97 4.55 9.29 3.062-J-3-1 141 1055 4.09 60.75 14.85 20.31 4.382-J-4-1 1 1068 5.22 85.20 1.94 7.64 2.09


Table 2 (continued)


Depth insection(cm)

Cumulativedepth(cm)

Gravel(%)

Sand(%)

Silt(%)

Clay(%)

Mean size(phi)

2-J-4-1 11 1078 11.85 80.58 1.43 6.13 2.472-J-4-1 21 1088 0.95 88.49 2.24 8.33 3.182-J-4-1 31 1098 9.43 68.90 7.02 14.65 3.442-J-4-1 41 1108 0.62 50.93 16.38 32.07 5.572-J-4-1 51 1118 0.21 12.61 20.75 66.43 8.732-J-4-1 61 1128 0.00 1.72 24.28 74.01 9.602-J-4-1 71 1138 0.00 1.98 26.75 71.27 9.432-J-4-1 81 1148 0.00 1.96 25.00 73.04 9.562-J-5-2 11 1181 0.19 1.78 26.00 72.03 9.492-J-5-2 21 1191 0.27 1.62 27.96 70.15 9.342-J-5-2 31 1201 0.00 1.41 26.74 71.84 9.472-J-5-2 41 1211 0.00 1.39 28.01 70.61 9.422-J-5-2 51 1221 0.00 1.18 23.20 75.61 9.642-J-5-2 61 1231 0.00 0.83 16.07 83.10 10.012-J-5-2 71 1241 0.00 0.98 20.70 78.32 9.752-J-5-2 81 1251 0.00 1.47 26.24 72.29 9.512-J-5-2 91 1261 0.08 1.39 25.77 72.76 9.542-J-5-2 101 1271 0.00 1.55 27.17 71.27 9.472-J-5-2 111 1281 0.00 0.79 28.74 70.46 9.442-J-5-2 121 1291 0.00 1.85 24.19 73.96 9.562-J-5-2 131 1301 0.00 2.23 32.98 64.78 9.072-J-5-2 141 1311 0.00 1.41 28.66 69.92 9.393-A-1-1 1 97 0.52 98.73 0.76 0.00 1.543-A-1-1 11 107 5.68 93.17 1.15 0.00 1.303-A-1-1 21 117 3.97 94.24 1.80 0.00 1.393-A-1-1 31 127 4.41 93.90 1.61 0.08 1.373-A-1-1 41 137 6.75 92.19 1.05 0.00 1.343-A-1-1 45 141 0.45 97.35 0.81 1.39 1.733-A-1-1 51 147 1.47 91.66 2.42 4.45 2.263-A-1-1 61 157 1.95 94.01 1.50 2.54 2.173-A-1-1 71 167 28.40 68.23 0.91 2.46 1.343-A-1-1 81 177 0.94 75.34 7.78 15.93 3.693-B-1-1 11 236 27.71 68.81 2.32 1.16 0.153-B-2-1 23 252 12.87 5.29 26.48 55.37 7.703-B-2-1 31 260 0.00 7.47 37.89 54.64 8.283-B-2-1 41 270 0.10 4.25 41.74 53.91 8.363-B-2-1 51 280 0.00 3.28 40.02 56.70 8.543-B-2-2 1 295 0.00 1.16 34.46 64.38 9.033-B-2-2 11 305 0.00 1.52 32.56 65.92 9.073-B-2-2 21 315 0.00 2.30 33.75 63.96 9.043-B-2-2 31 325 0.00 2.13 35.26 62.61 8.973-B-2-2 41 335 0.00 16.29 30.18 53.53 8.123-B-2-2 51 345 0.00 18.42 49.50 32.08 6.853-B-2-2 61 355 0.00 34.35 29.07 36.58 6.603-B-2-2 71 365 0.08 29.37 17.07 53.49 7.353-B-2-2 81 375 0.00 2.35 17.34 80.31 9.863-B-3-1 11 383 0.09 1.24 13.86 84.81 10.103-B-3-1 21 393 0.00 1.70 13.94 84.35 10.133-B-3-1 31 403 0.00 4.55 14.26 81.18 9.843-B-3-1 41 413 0.00 2.73 13.41 83.86 10.143-B-3-1 51 423 0.00 1.02 15.52 83.45 10.113-B-3-1 91 435 0.00 1.83 13.08 85.10 10.213-B-3-1 101 445 0.00 0.74 10.80 88.47 10.453-B-3-1 111 455 0.00 1.92 11.45 86.63 10.283-B-3-1 121 465 0.00 1.58 11.25 87.16 10.303-B-3-1 131 475 0.00 5.45 16.37 78.18 9.793-B-3-2 1 472 0.00 1.49 14.43 84.09 10.233-B-3-2 11 482 0.00 2.32 14.24 83.45 10.123-B-3-2 21 492 0.00 13.36 15.02 71.62 9.183-B-3-2 31 502 0.00 9.07 14.47 76.46 9.563-B-3-2 41 512 0.00 8.58 14.76 76.65 9.573-B-3-2 51 522 0.00 13.24 13.37 73.39 9.273-B-3-2 132 543 0.53 68.77 5.27 25.44 4.513-B-3-2 140 551 15.66 35.12 6.07 43.15 5.673-B-4-1 31 612 1.36 92.23 3.18 3.22 1.793-B-4-2 1 619 6.04 84.73 6.61 2.62 1.743-B-4-2 11 629 13.64 84.59 0.00 3.50 1.253-B-4-2 21 639 11.67 83.36 3.50 1.45 1.113-B-4-2 31 649 21.94 72.60 3.27 2.19 0.703-B-4-2 41 659 7.89 85.21 3.86 3.04 1.433-B-4-2 51 669 30.04 64.89 1.60 3.46 0.563-B-4-2 61 679 19.06 72.64 3.50 4.80 0.923-B-4-2 71 689 1.20 91.22 4.72 2.87 2.273-B-4-2 81 699 0.00 93.24 3.72 3.04 2.48

Table 2 (continued)


Depth insection(cm)

Cumulativedepth(cm)

Gravel(%)

Sand(%)

Silt(%)

Clay(%)

Mean size(phi)

3-B-4-2 91 709 1.67 91.40 3.85 3.08 2.213-B-4-2 101 719 2.52 84.51 5.90 7.07 1.923-B-4-2 111 729 0.00 87.12 8.08 4.80 2.603-B-4-2 121 739 0.00 86.87 2.81 10.32 2.593-B-4-2 131 749 0.00 90.88 5.32 3.79 2.593-B-4-2 141 759 0.02 62.20 21.00 16.78 2.62


adjustment does not explain the difference. The data are in agreementwith the Gulick et al. (2005) model. The mixed shallow assemblage isconsistent with erosion of sediments originally deposited duringMIS3a and MIS3b and subsequent deposition in deeper, middle-andouter shelf waters during sea- level fall associated with MIS 2. The ob-servedmixture of estuarine, inner-, and -middle-to -outer-shelf forami-nifera found in Units 1D, 1C and 1B is also consistent with this model.The high rate of sedimentation would also explain the low abundanceof in situ foraminifera found in these sediments (Table 4), especiallyfor Unit 1C.

An alternative depositional model involves reinvigoration of theHudson River system and deltaic sedimentation of older, eroded sed-iments at Site 1. In this model, estuarine sediments deposited duringMIS3 would have been eroded from the middle shelf during the sealevel fall into MIS2, and then fluvially deposited in a deltaic settingmuch like the feature (lowstand delta) identified in the HudsonCanyon region by McHugh et al. (2010). Carey et al. (2005) havemapped the paleo-Hudson drainage during MIS 3b to this general re-gion, providing a localized source. The abundant sediment availablefrom the paleo-Hudson could easily have been redistributed to Site 1,as sea level rose during MIS3a, through a combination of tidal currents,storms, and ocean currents on the then narrower, MIS3a shallow conti-nental shelf. The small fining-upward sequences throughout Unit 1C,and thicker, more episodic sequences in Unit 1B both show an increasein energy and sediment volume available for transport. However, wecurrently have no way to differentiate between these two depositionalmodels.

4.2. Site 2

Site 2 (Fig. 2; 39.0359° N, 73.0356°W; 79 m w.d.) penetrated13.1 mbsf in the middle shelf (~79 m w.d.) (Figs. 4 and 6), throughthe base of the thalweg of a large, infilled channel (Fig. 6), and terminat-ing above reflector R. The lowermost unit (2D) penetratesmuddy, OSWsediments similar to Unit D of Site 1. The iron-stained contact betweenunits 2D and 2C is interpreted as an exposure surface, indicating inci-sion and associated subaerial exposure duringMIS 2 (Fig. 4). Sedimentsinfilled the channel rapidly, with a total of ~10 m of sediment accumu-lating in b2 ky (Table 3; Fig. 6). Depositional rates of 0.5 to 1 cm/yr arecommon in modern fluvial and estuarine environments, but the ob-served infilling may have been a catastrophic release, perhaps of melt-water from a collapsing glacial lake to the north of the study area(e.g., Uchupi et al., 2001; Donnelly et al., 2005). Infilling occurred intwo phases. First, sands alternating with muds (Unit 2C) were deposit-ed on the incision surface. Then it appears that the channel was re-cutand modified before an upper, sandier unit (Unit 2B) was deposited.This site has only a thin cap of the Holocene sand sheet (Unit 2A).

4.2.1. Unit 2D: 1320 (Base) to 1112 cmbsf (2J-5-2, 150 cm to 2J-4-1,45 cm)

This unit has very low percentages of sand (b2.5%) and high abun-dances of clay (65%–76%) (Table 2; Fig. 6). The muds are stiff and lami-nated. Foraminiferal abundance is moderate (56–118 individuals) anddominated by Elphidium spp. (Table 4; Fig. 6), many of which areiron-stained, suggesting inner -middle shelf depositional conditions.

Table 3AMS 14C radiocarbon dates. Ages were calibrated using CALIB 6.0.

Site Sample depth(mbsf)

CAIS/UGA lab code Material δ13C 14C age(yr BP)

± Calibrated age(cal BP)

± Age range(cal BP, 2σ)

Calibration fileused

1 0.40 R50526 Bivalve 1.68 10,205 36 10,800 170 10,575–11,079 Marine091.30 R50527 Bivalve 0.09 32,300 122 35,896 120 35,336–36,014 Marine094.70 R50522 Bivalve −1.47 40,323 213 43,672 210 43,131–44,205 Marine09

2 0.99 R50529 Gastropod −0.45 12,565 41 13,648 150 13,423–13,832 Marine092.95 R50520 Wood −27.03 12,294 44 14,198 200 13,969–14,582 Intcal094.28 R50525 Bivalve −0.67 13,522 42 15,195 980 14,664–15,699 Marine095.28 R50519 Wood −28.18 12,285 45 14,177 200 13,955–14,571 Intcal096.37 R50524 Bivalve −1.66 13,417 46 14,979 930 14,282–14,332 Marine097.83 R00628 Wood −24.99 12,232 103 14,139 210 13,814–14,642 Intcal099.53 R00629 Bivalve −1.69 14,075 95 16,363 350 15,545–16,844 Marine0910.81 R50530 Bivalve −0.93 13,542 62 15,251 1000 14,649–15,933 Marine0912.16 R00630 Bivalve 0.65 49,153 2538 48,420⁎ – – None

3 1.25 R50523 Bivalve 1.73 689 27 Modern⁎ – – none1.29 R00631 Bivalve 0.50 7450 91 7600 110 7398–7842 Marine091.38 R50531 Bivalve 2.13 4372 29 4066 170 3831–4313 Marine095.29 R50533 Bivalve 0.74 37,387 152 41,663 150 41,270–42,047 Marine095.53 R50532 Bivalve 1.97 34,067 138 38,116 140 37,384–38,697 Marine096.27 R50534 Gastropod 0.62 41,404 235 44,511 240 44,052–45,040 Marine097.13 R50536 Bivalve 0.03 36,763 157 41,239 160 40,794–41,693 Marine09

All samples were analyzed at the Center for Applied Isotope Studies (CAIS), Athens, GA and are identified by 3 digit (UGA) or 5 digit (CAIS) laboratory codes.Calibrated using CALIB 6.0 and following Stuiver and Reimer (1993), Radiocarbon, 35, 215–230.Cal BP — calibrated age, DR for marine samples (333±78 yr) from Marine Reservoir Correction Database (Reimer, P.J.).⁎ Uncalibrated age; marine reservoir correction of 733 yr subtracted.


Cibicioides spp. (middle -outer shelf) is present, but at very low abun-dance (~2%). We interpret the contact between Unit 2D and Unit 2C,which contains iron-stained interval foraminifera (see photographicinset d in Fig. 6), as an exposure surface (Figs. 4 and 6). An uncorrectedradiocarbon date, 48.42+0.25 ka (Table 3), made on a bivalve test at~1216 cmbsf, could indicate that the sediments were deposited duringearly MIS3 3c or 3b. However, this age is beyond the limit of calibrationand close to the limits of the 14C technique, so it is possible that the ageis a minimum age. Given the similarity in texture and foraminiferal as-semblage to Site 1, Unit D, and its relative position above R in the uppertransparent unit of the OSW (Fig. 4), Unit D of Site 2 is probably equiv-alent to Unit D of Site 1.

4.2.2. Unit 2C: 1112–642 cmbsf (2J-4-1, 45 cm to 2-I-2, 98cm)This interpreted channel-fill unit is divided into four sequences,

which we suggest represents a multi-phase infilling of the observedincision; the crossing CHIRP profile supports this interpretation(Fig. 6). Unit 2C4 (1112–1037 cmbsf; 2J-4-1, 45 to 2J-3-1, 123) isthe lowermost section of this unit and is dominated by shelly,interbedded sands which we interpret as a channel lag (Fig. 4, photo-graphic inset c of Fig. 6; Table 2). There are very few foraminifera, butthose present indicate an inner shelf environment (Figs. 4 and 6;Table 4). A radiocarbon date, 15.25+1.00 ka (Table 3) at 1081 cmbsf,indicates that the fill was deposited around the MIS2/1 boundary. Unit2C3 (1037–827 cmbsf; 2J-3-1, 123 to 2J-2-1, 35) consists of laminatedsands and muds, and contains mica and wood fragments indicative ofa terrestrial source. Foraminifera are generally abundant and dominat-ed by Elphidium spp., indicative of an estuarine environment, withsome middle shelf elements (Quinqueloculina spp.) (Table 4; Fig. 6).The Elphidium spp. are also iron-stained, consistentwith either reducingconditions (i.e., beneath an ambient freshwater table) or occasionalsubaerial exposure. Unit 2C2 (827–740 cmbsf; 2J-2-1, 35 to 2J-1-2,98) is dominated by fine sands with shell hash. The base of Unit 2C2 isdefined by pebbles (Figs. 4 and 6). Wood and shell fragments are com-mon, and a long burrow is present. The foraminiferal assemblage is sim-ilar to Unit 2C3, representing an inner shelf environment. Unit 2C1(740–642; 2J-1-2, 98 to 2J-1-2, 0) consists of interbedded muds andsands, contains wood, and the foraminiferal assemblage is dominatedby Elphidium spp. suggestive of estuarine to inner shelf conditions.There are species from deeper waters (Quinqueloculina spp.) (Figs. 4and 6), too, but they are found at very low abundances (b1%) and

are transported. (See photographic inset c of Fig. 6 for the 2C2/C1boundary)

4.2.3. Unit 2B: 642–35 cmbsf (2I-1-2, 150 to 2C-1-1, 24 cm)This unit is dominantly sands (Figs. 4 and 6; Table 2), with a few

pulses of gravel/shell hash between ~550 and 483 cmbsf, consistentwith a high-energy, inner shelf environment. Unit 2B2 consists ofshelly sands which dominate from 640 to 483 cmbsf (see photo-graphic inset b, Fig. 6). Unit 2B1 consists of massive sands from 473to 234 cmbsf capped by sands containing a fine shell hash (Figs. 4and 6; Table 2) (see photographic inset a, Fig. 6). Most of Unit 2B isbarren of foraminifera or contains very few specimens (b10 individ-uals). The few samples that contain more than ten individuals suggestan inner shelf environment but, as with Unit C, the assemblage alsocontains deeper water elements at low abundance (Fig. 6; Table 4).Wood is common, and the Elphidium spp. are not iron stained,suggesting that they were not deposited in a reducing environmentor subaerially exposed. Deeper water specimens, such as Cibicidoidesspp. and Quinqueloculina spp., are broken and abraded, evidence of arelict or reworked assemblage. Pteropods are present through theunit, even when foraminifera are found in low abundances or barren.Since pteropods are aragonitic and dissolve more easily than carbon-ate, the observed paucity of foraminifera may be due to dilution andnot dissolution.

The radiocarbon dates indicate that Units 2B2 and 2B1 were de-posited essentially instantaneously: the shells and wood were depos-ited at approximately the same time (Table 3). Sedimentation ratesare extremely high, approaching 690 cm/ky (Table 3). The δ13C isoto-pic composition of shell material, which varies among marine shells(4.2 to −1.7‰), fluvial shells (−8.3 to −15.2‰), and terrestriallake shells (6.0 to −2.4‰) (Keith et al., 1964), suggests all the shellmaterial has a marine rather than fluvial origin (Table 3), althoughthere is overlap with lake values. The wood δ13C reflects a terrestrialsource (Table 3), as would be expected.

4.2.4. Unit 2A: 35 cmbsf — top. (2C-1-H-1, 24 to 2C-1-H-1, 0)This unit is separated from Unit 2B by an abrupt contact at

35 cmbsf (Fig. 4). Unit 2A sands are coarse grained, containing mudclasts and shell hash (Figs. 4 and 6), and is similar in thickness toUnit 2A at Site 1. Foraminifera indicate a middle-outer shelf assem-blage (Fig. 6; Table 4). A pteropod, which is generally a pelagic


species, was also found in the sample at 19 cmbsf, in what we inter-pret as a modern, Holocene sand sheet deposit.

4.2.5. Depositional history of Site 2Based on textural and paleontological similarities, we interpret

Unit D at Site 2 to be part of the OSW complex (Fig. 4). Subsequentchannel formation is constrained to a period when sea level droppedsignificantly, between ~30 ka and the LGM. The initial incision was awide, asymmetric channel (Fig. 6) that was infilled by two sequences(units 2C and 2B) in a generally inner shelf environment throughoutthe latest MIS2 (~15–14 ka).

The Units 2C and 2B infilling sequence was complex but rapid(Figs. 4–6). A basal layer of shelly, interbedded muds and sands indi-cates deposition in a shallow marine environment, soon after fluvialerosion creating the initial incision. Fining upward is evident in theensuing channel infilling, occurring ~15 ka (C4). Infilling continued(Unit 2C3) at lower energy, resulting in observed laminations. Flowwas then reinvigorated, marked by a shell and pebble hash at thebase of Unit 2C2. This flow apparently cut down into previously de-posited 2C3 sediments andmay have cut one of the ancillary channelsobserved in the CHIRP profile crossing Site 2 (Fig. 6). A coarsening up-wards sequence defines Units 2C2 and 2C1, which fill much of thecross-section of the main channel. Based on estimates of sea level atthe time (e.g., Wright et al., 2009), the shoreline just after the LGMwas positioned in this area (Fig. 5). This interpretation is consistentwith reconstructions by Nordfjord et al. (2005) that show interpretedfluvial channels flooding rapidly and functioning like estuaries. Our14C ages (Table 3) place sedimentation within the slower sea-levelrise associated with initial deglaciation (Fig. 5).

A U-shaped channel is associated with Unit 2B deposition ~15 ka,terminating around 13.6 ka. This phase of sedimentation occurred rap-idly and would have been facilitated by the higher sea level associatedwith MWP-1a (see Fig. 5). This rapid rise in sea level shifted the coast-line west of the study area; offshore flow was restricted to channels atfirst, with infilling rapidly following downcutting. The Site 2 region ulti-mately reached a stable inner shelf environment, as illustrated by theoverall coarsening-upwards of Unit 2B, which was predicted by themodeling of Nordfjord et al. (2005). Upon completion of infilling, no sig-nificant sediment accumulated in this area until the Holocene sandsheet (Unit 2A) capped the stratigraphic section at this location.

We consider it unlikely that Site 2 was impacted by subsi-dence associated with the collapse of the peripheral bulge during de-glaciation. Dillon and Oldale (1978) have calculated subsidence rates(10.5 mm/yr) consistent with depositional rates for Site 2, but: 1) theseare for the area north of the hinge zone, and 2) if subsidence were driv-ing sedimentation at Site 2, deposition should have continued past13 ka, as their study indicates high rates of subsidence occurred until9 ka. The ~1 m thick unit of glauconitic sands identified north of theHudson Canyon (McHugh et al., 2010) may be a result of increased ac-commodation space north of the hinge zone.

4.3. Site 3

Site 3 (39.2533°N, 72.8998°W) (Fig. 2) penetrated 7.7 mbsf, throughthe surficial sand sheet, theflankof anotherfilled channel and the “R” ero-sional unconformity in 75 m w.d. (Figs. 4 and 7). The interpreted expo-sure surface “R” (Milliman et al., 1990; Davies et al., 1992; Duncan et al.,2000; Gulick et al., 2005) is recognized by iron staining and its induration,but the latter limited analysis bothwithin theunits containing R (Unit 3D)and pre-R (Units 3E and 3F). Associated shell hash, sand-prone sedi-ments, and foraminiferal assemblages all indicate a nearshore marinesystem that, after exposure, was overlain by reworked sediments of theOSW (Unit 3C). Downcutting associated with glaciation/shelf exposureled to channel formation (Unit 3C) and then infilling as sea level rose(Unit 3B). Site 3 is again capped with the regional sand sheet (Unit 3A).

4.3.1. Unit 3F: 768 (Base) to 752 cmbsf (3B-4-2, 150 to 3B-4 -2, 124 cm)This unit is composed of very hard, indurated dark gray muds

(Figs. 4and 7; Table 2) that caused drilling refusal and were difficultto sample and process (see photographic inset f, Fig. 7). Abundantiron-stained Elphidium spp. (95%) dominate this inner-shelf forami-niferal assemblage (Fig. 7; Table 4). Superposition mandates thisunit is older than the material in overlying Unit E, so these mudsmust have been deposited at least 41 ka, but are likely older, giventheir induration. We suggest that this Pre-R unit was probably depos-ited during MIS 6 or MIS 4 (Fig. 5).

4.3.2. Unit 3E: 752 to 682 cmbsf (3B-4-2,124–64)Unit 3E is composed of sands with mud balls and shell fragments

between ~728 and 718 cmbsf (Figs. 4 and 7; Table 2). We interpretedthese as indicative of a high-energy inner-shelf system. This unit wasnot sampled for foraminifera. A 14C age determination on shell materialat 713 cmbsf indicates deposition in MIS 3b (41.2+0.16 ka) (Table 3),possibly around the MIS 3b/ 3a boundary, although if the shell istransported, deposition may have occurred later than the 14C age deter-minations indicate. The contact with overlying Unit 3D (reflector R)(see photographic inset e, Fig. 7) is defined by an increase in shell hashand orange staining, which we suggest is associated with exposure.

4.3.3. Unit 3D (Reflector R): 682 to 588 cmbsf. (3B-4-2, 64–3B-3-2, 116)We interpret this unit as an exposure surface composed of indurat-

ed, iron-stained sands and muds (Figs. 4 and 7), the base of regional re-flector R. We further divide Unit 3D into two subunits: Unit 3D2 (682–671 cmbsf; 3B-4-2, 64–53), which is composed of iron-stained sandsand muds, and Unit 3D1 (671–588 cmbsf; 3B-4-2, 53–3B-3-2, 116),which consists of sands and shell hash, with intervals of orange-colored sediments with mud at its top. Foraminifera from Unit 3D1 aredominated by Elphidium spp. (56%), with the only other componentsmostly abraded Cibicides spp. (43%) and Quinqueloculina spp. (1%),suggesting an inner shelf environment containing reworked deeperwater components. A 14C date (44.51+.24 ka) at 627 cmbsf, within3D1, falls in MIS 3b, near the 3b/3a boundary (Fig. 5; Table 3). This isslightly older than that the shell material from underlying Unit 3E, sothematerial dated was either eroded from an older unit or altered by ex-posure. The presence of shell hash indicates a high-energy nearshore en-vironment consistent with transport, erosion, and subaerial exposure.Again, the uncalibrated agequoted above is difficult to place in a temporalframework, but the data restricts the age of the upper part of R to ~41 ka.The contact with overlying Unit 3C is visible in the photographic inset d,Fig. 7.

4.3.4. Unit C: 588–358 cmbsf (3B-3-2, 116–3B-2-2, 64)Unit C lithology is mainly clayey mud (Fig. 4, see photographic in-

sets c, d in Fig. 7; Table 2). Foraminifera near the base (526 cmbsf)(Fig. 7; Table 4) are dominated by estuarine components (Elphidiumspp. and A. becarii), a depositional environment which is consistentwith the lithology; furthermore, some of the individuals are ironstained, suggesting a reducing environment and/or subaerial expo-sure, either of which could occur in an estuary. The deeper waterCibicides spp. (19%) and Quinqueloculina spp. (3%) are present, butconsidered relict because they are abraded. Sponge spicules are alsopresent. Shells near the base of the unit are dated at 38.12+.14 ka(553 cmbsf) and 41.66+0.15 ka (529 cmbsf) (MIS 3b/3a; Fig. 5;Table 3). This unit sampled sediments above R (Unit 3D), but belowthe interpreted incised channel (Unit 3B). The inverted shell agesmay be explained by transport or diagenesis associated with the for-mation of R.

4.3.5. Unit 3B: 358–235 cmbsf (3B-2-2, 64 – 3B-2-1, 22)Unit 3B is associated with infilling of a channel (Figs. 4 and 7;

Table 2). Orange-stained, sandy muds define the channel wall, evi-dent from the CHIRP data (Fig. 7), which forms a gradual contact

Table 4Benthic foraminiferal data by species and genera. Total number of foraminifera was used to calculate relative abundance. Samples with few (b50) specimen are italicized.


Depth insection(cm)

Cumulativedepth(cm)

No. ofbenthicforaminifera

Relative abundance of benthic foraminifera

%Elphidiumspp.

%Islandiellaspp.

%Globocassidulinaspp.

%Cassidulinaspp.

%Quinqueloculinaspp.

%Lenticulinaspp.

%Cibicidoidesspp.

1-A-1-1 37–39 38 231 6 25 0 0 1 7 271-A-1-2 14–17 60 720 15 12 11 0 1 3 221-A-1-2 104–107 150 353 37 7 20 0 6 0 221-A-1-2 115–118 161 503 72 1 6 0 9 0 101-A-1-2 124–128 170.5 0 0 0 0 0 0 0 01-A-1-2 133–135 178.5 1 100 0 0 0 0 0 01-A-1-2 147–150 193 1 100 0 0 0 0 0 01-A-2-1 13–16 219.5 17 47 0 6 0 12 12 61-A-2-1 45–47 251 0 100 0 0 0 0 0 01-A-2-1 74–77 280.5 8 75 0 13 0 0 13 01-A-2-2 36–39 352.5 139 100 0 0 0 0 0 01-A-2-2 45–47 361 32 97 0 3 0 0 0 01-A-2-2 143–147 460 123 80 0 6 0 3 0 32-C-1-1 2–6 15 377 14 4 7 0 2 5 442-C-1-1 7–9 19 255 13 2 7 0 6 6 422-C-1-1 12–14 24 76 76 0 0 0 11 1 82-C-1-1 17–19 29 1 100 0 0 0 0 0 02-C-1-1 21–23 33 1 100 0 0 0 0 0 02-C-1-1 27–29 39 9 78 0 0 0 11 0 112-C-1-1 78–80 90 5 80 0 0 0 20 0 02-H-1-1 10–12 224 0 0 0 0 0 0 0 02-H-1-1 17–19 231 3 67 0 0 0 0 0 02-H-1-2 124–128 449 0 0 0 0 0 0 0 02-I-1-1 42–44 42 95 0 0 0 5 0 02-I-1-1 42–46 486 0 0 0 0 0 0 0 02-I-1-2 7–9 507 0 0 0 0 0 0 0 02-I-1-2 13–16 513.5 34 91 0 0 0 6 0 32-I-1-2 64–67 564.5 7 86 0 0 0 14 0 02-I-1-2 134–138 635 11 55 0 0 0 18 0 182-J-1-1 7–9 28 100 0 0 0 0 0 02-J-1-2 6–9 649.5 337 99 0 0 0 0 0 02-J-1-2 36–38 679 346 97 0 0 0 2 0 02-J-1-2 89–91 732 307 99 0 0 0 0 0 02-J-1-2 98–102 742 302 99 0 0 0 0 0 12-J-1-2 124–128 768 401 99 0 0 0 0 0 02-J-1-2 143–147 787 299 98 0 0 0 1 0 12-J-2-1 5–7 798 303 96 0 0 0 2 0 22-J-2-1 26–28 819 194 97 0 0 0 3 0 02-J-2-1 32–34 825 167 97 0 1 0 2 0 02-J-2-1 35–37 829 472 99 0 0 0 1 0 02-J-2-1 64–66 857 243 97 0 0 0 2 0 02-J-2-1 67–70 860.5 446 96 0 0 0 0 0 02-J-2-1 103–105 896 392 98 0 0 0 1 0 02-J-3-1 16–20 932 545 98 0 0 0 0 0 02-J-3-1 60–62 975 307 99 0 0 0 0 0 02-J-3-1 117–119 1032 318 98 0 0 0 1 0 12-J-3-1 122–124 1037 307 96 0 0 0 1 0 12-J-3-1 124–126 1039 241 98 0 0 0 0 0 02-J-4-1 40–42 1108 0 0 0 0 0 0 0 02-J-4-1 42–44 1110 7 100 0 0 0 0 0 02-J-4-1 52–54 1120 118 96 0 0 0 1 0 02-J-5-1 54–58 1126 93 89 0 0 0 8 0 12-J-5-1 134–138 1306 56 89 0 0 0 5 0 23-A-1-1 44–46 141 129 29 0 3 0 3 2 573-B-1-1 4–8 231 34 32 0 3 0 0 3 443-B-2-1 22–24 252 631 96 0 0 0 0 0 03-B-2-1 24–26 254 528 98 0 0 0 0 0 03-B-2-1 56–59 286.5 409 89 0 0 0 0 0 03-B-2-2 4–8 300 495 86 0 0 0 0 0 03-B-2-2 34–36 329 22 86 0 0 0 0 0 03-B-2-2 40–44 336 3 67 0 0 0 0 0 03-B-2-2 63–65 358 0 0 0 0 0 0 0 03-B-3-2 114–116 256 75 0 0 1 3 0 193-B-3-2 147–149 559 75 56 0 0 0 1 0 433-B-4-2 148–150 767 401 95 0 0 0 3 0 1

**Intervals with very low (b50) specimen are italicized.


between Units 3C and Unit 3B (352–344 cmbsf). Unit 3C is capped by athin (9 cm) shell hash that enhances the incision reflector, and Unit 3Bmuds account for the acoustically transparent infill (Fig. 7). The

foraminiferal assemblages are estuarine to inner shelf (Fig. 7;Table 4), and have a high number of individuals. The sample from300 cm, with 330 individuals, has a clearly defined estuarine signal: A.

Table 4Benthic foraminiferal data by species and genera. Total number of foraminifera was used to calculate relative abundance. Samples with few (b50) specimen are italicized.


%Ammoniabeccarii

%Trochaminainflata

%Buliminaaculeata

>%Buliminamarginata

%Buliminasp. A

%Bulliminellaspp.

%Angulogenerinaangulosa

%Bolivinasp. A

%Gyroidinoidesspp.

%Melonisbarleeanum

%Marginulopsisspp.

0 0 1 2 3 0 11 0 0 1 50 0 0 3 13 0 12 0 0 0 21 0 0 4 2 1 0 0 0 0 00 0 0 0 1 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 12 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 08 0 0 0 0 0 0 0 0 0 01 1 1 0 14 1 2 0 0 0 10 0 0 0 20 0 3 0 0 0 00 0 0 1 0 1 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 0

33 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 09 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 01 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 01 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 01 0 0 0 0 0 0 0 0 0 01 0 0 0 0 0 0 0 0 0 01 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 02 0 0 0 0 0 0 0 0 0 01 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 01 0 0 0 2 0 0 0 0 0 02 0 0 0 0 0 0 0 0 0 02 0 0 0 0 0 0 0 0 0 00 0 0 2 3 0 1 0 0 0 00 0 0 6 6 0 0 0 0 0 03 0 0 0 0 0 0 0 0 0 02 0 0 0 0 0 0 0 0 0 0

11 0 0 0 0 0 0 0 0 0 014 0 0 0 0 0 0 0 0 0 014 0 0 0 0 0 0 0 0 0 033 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 01 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 0 0 0 0


becarri (33.3%) and Elphidium spp. (67%). Unfortunately, there is no 14Cage control for the remainder of this interval. Given that Unit 3B overliesthe channel and that a K–Ar date on hornblendes at 358 cmbsf (Table 5)is similar in age to the sample at 141 cmbsf (Site 3, Unit A) (see

discussion in Section 4.4), Unit 3B deposition likely began in late MIS2, after the channel was eroded. Unit 3B has a similar faunal assemblageto Site 2 Unit C (Fig. 4), suggesting that it, too, is channel fill. The top ofUnit 3B is shelly (see photographic inset b, Fig. 7).

Table 4 (continued)Benthic foraminiferal data by species and genera. Total number of foraminifera was used to calculate relative abundance. Samples with few (b50) specimen are italicized.



%Uvigerinaperegrina

%Pyrghospp.

textularids %Lagenaspp.

%Sphaeroidinellopsisbulloides

%Guttulinaspp.

%Polymorphinind

%Osangulariaspp.

%Plectofrondicularaspp.

%Pulliniaspp.

Other Total

1-A-1-1 1 1 3 0 2 1 0 0 0 0 1 1001-A-1-2 1 0 2 0 0 0 0 0 0 0 0 1001-A-1-2 0 0 0 0 0 0 0 0 0 0 0 1001-A-1-2 0 0 0 0 0 0 1 0 0 0 0 1001-A-1-2 0 0 0 0 0 0 0 0 0 0 0 01-A-1-2 0 0 0 0 0 0 0 0 0 0 0 1001-A-1-2 0 0 0 0 0 0 0 0 0 0 0 1001-A-2-1 0 0 0 0 0 0 0 0 0 0 6 1001-A-2-1 0 0 0 0 0 0 0 0 0 0 0 1001-A-2-1 0 0 0 0 0 0 0 0 0 0 0 1001-A-2-2 0 0 0 0 0 0 0 0 0 0 0 1001-A-2-2 0 0 0 0 0 0 0 0 0 0 0 1001-A-2-2 0 0 0 0 0 0 0 0 0 0 0 1002-C-1-1 0 0 0 0 0 1 1 0 0 0 0 1002-C-1-1 0 0 1 0 0 0 0 0 0 0 0 1002-C-1-1 0 0 0 0 0 0 0 0 0 0 0 992-C-1-1 0 0 0 0 0 0 0 0 0 0 0 1002-C-1-1 0 0 0 0 0 0 0 0 0 0 0 1002-C-1-1 0 0 0 0 0 0 0 0 0 0 0 1002-C-1-1 0 0 0 0 0 0 0 0 0 0 0 1002-H-1-1 0 0 0 0 0 0 0 0 0 0 0 02-H-1-1 0 0 0 0 0 0 0 0 0 0 0 1002-H-1-2 0 0 0 0 0 0 0 0 0 0 0 02-I-1-1 0 0 0 0 0 0 0 0 0 0 0 1002-I-1-1 0 0 0 0 0 0 0 0 0 0 0 02-I-1-2 0 0 0 0 0 0 0 0 0 0 0 02-I-1-2 0 0 0 0 0 0 0 0 0 0 0 1002-I-1-2 0 0 0 0 0 0 0 0 0 0 0 1002-I-1-2 0 0 0 0 0 0 0 0 0 0 0 1002-J-1-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-1-2 0 0 0 0 0 0 0 0 0 0 0 1002-J-1-2 0 0 0 0 0 0 0 0 0 0 0 1002-J-1-2 0 0 0 0 0 0 0 0 0 0 0 1002-J-1-2 0 0 0 0 0 0 0 0 0 0 0 1002-J-1-2 0 0 0 0 0 0 0 0 0 0 0 1002-J-1-2 0 0 0 0 0 0 0 0 0 0 0 1002-J-2-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-2-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-2-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-2-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-2-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-2-1 0 0 0 0 0 0 0 0 0 0 0 982-J-2-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-3-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-3-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-3-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-3-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-3-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-4-1 0 0 0 0 0 0 0 0 0 0 0 02-J-4-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-4-1 0 0 0 1 0 0 0 0 0 0 0 1002-J-5-1 0 0 0 0 0 0 0 0 0 0 0 1002-J-5-1 0 0 0 0 0 0 0 0 0 0 2 1003-A-1-1 0 0 0 0 0 0 0 0 0 0 0 1003-B-1-1 0 0 0 0 0 3 3 0 0 0 0 1003-B-2-1 0 0 0 0 0 0 0 0 0 0 0 1003-B-2-1 0 0 0 0 0 0 0 0 0 0 0 1003-B-2-1 0 0 0 0 0 0 0 0 0 0 0 1003-B-2-2 0 0 0 0 0 0 0 0 0 0 0 1003-B-2-2 0 0 0 0 0 0 0 0 0 0 0 1003-B-2-2 0 0 0 0 0 0 0 0 0 0 0 1003-B-2-2 0 0 0 0 0 0 0 0 0 0 0 03-B-3-2 0 0 0 0 0 0 0 0 0 0 0 1003-B-3-2 0 0 0 0 0 0 0 0 0 0 0 1003-B-4-2 0 0 0 0 0 0 0 0 0 0 0 100


4.3.6. Unit 3A: 182 to 96 cmbsf (top) (3A-1-1, 42-0)Unit A is composed of sands with shell hash (Figs. 4 and 7;

Table 2). Shell layers are concentrated between 128 and 118 cmbsf.Foraminifera indicate a middle-shelf environment, consistent with

the Holocene paleodepths. The assemblages contain abraded compo-nents of older, transported inner-shelf foraminifera (Fig. 7; Table 4).The 14C dates on shell material at 138 (4.07±.17 ka), 91 cmbsf(7.60±.11 ka), and 125 cmbsf (~Modern) (Table 3) all confirm that

Table 5Potassium–argon age determinations for hornblende crystals. Methods are detailed in Turner (2005). Values are plotted on lower panels of Figs. 3 and 7.

Site Depth(cmbsf)

Unit Lat. Long. Size fraction(mm)

K(wt.%)

40Ar*(%)

40A*(pmol/g)

K–Ar age(m.y.)

1 16 A 39.24 72.69 125–250 1.17+0.02 90 2.47+0.05 930+201 60 A 39.24 72.69 125–250 0.93±0.03 97 1.97±0.04 930±201 150 B 39.24 72.69 125–250 1.15±0.02 97 2.17±0.04 850±203 141 A 39.25 72.9 125–250 1.02+0.02 97 2.27+0.04 960+203 358 B 39.25 72.9 125–250 1.09+0.03 97 2.38+0.04 960+303 767 F 39.25 72.9 63–250 0.99+0.03 90 1.93+0.07 880+30

Water D

epth (m)

2

4

3a3c

3b

6

5e

Age (ka)0 50

Pre- “R”Hol

ocen

e V

enee

r

Inci

sion

“R”

MWP- 1A

100

0

100

50

150

5b

MIS 3b

paleo-Hudsonvalley

Site 1

Site 2

Site 3

Post-LGM/ MPW1a

Site 1

Site 2

Site 3

LGM

Site 2

Site 3

MIS 4/6

paleo-Hudsonvalley

Site 1

Site 2

Site 3

MIS 3/2

paleo-Hudsonvalley

Site 1

Site 2

Site 3

Infil

l

3b

Fig. 5. Timing of sea level and paleoshorelines on the NJ margin. The NJ sea level curve of Wright et al. (2009) is shown in red circles with black error bars, and marine isotope stage(MIS) numbers are indicated in black. The timing of R deposition is noted in gray, fluvial incision by green, and infill by purple. Timing of Meltwater Pulse-1A (MWP-1A) is indicatedby the black arrow. Schematic approximations of paleoshoreline are included for MIS 6 (olive), MIS 4 (light green), MIS 3b (blue), MIS 3/2 transition (yellow), LGM (orange), andMWP-1a (purple) and were created using our sea level estimates drawn on modern bathymetric lines. Fluvial incisions mapped by Nordfjord et al. (2005) are shown in dark green.Paleo-Hudson positions mapped by Carey et al. (2005) are show in black.


Gravel(%)

500 401000

Sand(%)

600

Silt(%)

1000

Clay(%)

6000


1000

Elphidium spp.(%)

0

A. beccarii(%)

500

Cib. spp.(%)

250


Lithologic Units

13.6 Ka

14.2 Ka

15.2 Ka

14.2 Ka

15 Ka

14.1 Ka

16.4 Ka

15.2 Ka

48.4 Ka

1400

0

400

800

1000

1200

600

200

1400

0

400

800

1000

1200

600

200

A

B

B

D

C

Site 20 50 m

0

5 m

10

a

d

b

c

A

B

C

D

B

Dep

th (

cm)

a b c d

NS

Fig. 6. CHIRP profile 326 and lithostratigraphic, textural and foraminiferal results for Site 2. Radiocarbon ages (see Table 3) are shown in red (Shell) and green (Wood). Red verticalline indicates the core location and approximate depth of penetration. Photographic insets illustrate significant lithologies and contacts (a=Unit B, 2H-1-2, 90–120 cm; b= Unit B,-2-I-1-2, 120–150 cm; c = Unit C1/C2 Boundary, 2J-1-2, 84–105 cm; d = Unit C4/D Boundary, 2-J-4-1, 33–53 cm) and their approximate stratigraphic positions are shown on theCHIRP line. Note the onlapping of channel infill sediments, and the seismic evidence for multiple erosional episodes within the channel. Water depth is ~79 m, depth to base of coreis ~13 mbsf, and vertical exaggeration is ~6.5×. Key to lithology is found in Fig. 4.


Unit 3A is part of the widespread and actively mixed Holocene sandsheet found in this region. Unit A at Site 3 is similar to the uppermostunits at both sites 1 and 2 (Figs. 3, 4, 6, and 7; Table 2).

4.3.7. Depositional history of Site 3Site 3 sediments below the interpreted filled fluvial channel are

stratigraphically the oldest sampled in the study area. The sequenceincludes inner shelf to estuarine deposition during MIS4 or MIS6(Unit F) and MIS 3b (Unit E), formation of R during MIS 3b/a or MIS3b (Unit D), deposition of mixed OSW sediments during MIS 3a(Unit C), MIS2 incision and then infilling in late MIS 2 (Unit B), andcapping with a sand sheet in MIS 1 (Unit A). The basal unit (F) ofSite 3 is not recognized at any of the other sites (Fig. 4). Since sealevel during MIS 4 was ~75 m lower than modern (Wright et al.,2009; Fig. 5), Site 3 (75 m modern w.d.) Unit 3F would have been

deposited under shallow-water conditions, consistent with the abun-dant Elphidium spp. McHugh et al. (2010) identify a reflector, p1, asMIS 7/6 and so Unit 3F may be the result of the rise in sea level follow-ing the penultimate glacial (Fig. 5). The lithology of the pre-R Unit 3Esediments (sands, shell hash, and mud balls) is also consistent withthe shallow water depths predicted for MIS 3b on the NJ shelf(75 m–65 m=10 m w.d.) (Fig. 5). An age of ~41 ka for R places theformation of R around the MIS3b/MIS3a boundary (Wright et al.,2009), and in agreement with the estimates of Gulick et al. (2005).But R is an exposure surface, and so the age of formation is probablyearlier, in MIS3b, as sea level fell to around −65 m wd (~45 ka).Either age is in agreement with the formation of possible ice scoursmapped on R by Goff and Austin (2009).

Unit 3C contains amixture of estuarine to inner/middle shelf forami-nifera with shell material at the base dated at ~42–38 ka (MIS3a). This

“Channels”

“R”

Seafloor0

5 m

10

0 50 m

A. beccarii(%)

4000

Elphidium spp.(%)

Gravel(%)

500 1000

Sand(%)

600

Silt(%)

1000

Clay(%)

7000


K/Ar Age(Ma)

Lithologic Units

0

100

200

300

400

500

600

700

800

Dep

th (

cm)

A

BB

C

DE

F

CFe Fe Fe

Fe

100

Cib. spp.(%)

600


150

960 + 20

960 + 30

880 + 30

500

0

100

200

300

400

600

700

800

7.6 Ka

4.1 Ka

41.7 Ka

38.1 Ka

44.5 Ka

41.2 Ka

a

bc

def

a b c d e f

D2

NSSite 3

Fig. 7. CHIRP line 161 and lithostratigraphic, textural and foraminiferal results for Site 3. Radiocarbon ages (see Table 3) are shown as horizontal red lines. Red vertical line indicates the core location and approximate depth of penetration.Photographic insets of split core faces illustrate significant lithologies and contacts. (a = Unit A, 3-A-1-1, 27–47 cm; b = Unit B, 3-B-2-1, 28–40 cm; c = Unit C, 3-B-3-2, 110–130 cm; d = Unit C/D Contact, 3-B-1-1, 3–20 cm; e = Unit D/EContact, 3-B-4-2, 42–82 cm; f = Unit F, 3-B-4-2, 120–150 cm) and their relative stratigraphic positions are shown on the CHIRP line. Depths of hornblende analyses and age of crystals are shown (see Table 5). Water depth is ~75 m, depth tobase of core is ~8 mbsf, and vertical exaggeration is ~5.5×. Key to the lithology is found in Fig. 4.

95B.A

.Christensenet

al./Marine

Geology

335(2013)

78–99


unit is probably the same as sediments sampled by Knebel and Spiker(1977), which yielded a recalibrated radiocarbon age of ~32 ka. MIS3awater depths for Site 3 were ~40 m (Fig. 5), deeper than the foraminif-eral data indicate. As at Site 1 Units D and C, Site 3 Unit C has very lowbenthic foraminiferal abundances and the muddy sediments are domi-nated by inner-middle shelf species. We interpret Unit 3C as outer shelfsediment veneer, proposed by Gulick et al. (2005) to have formed be-tween 33 and 31 ka in the vicinity of Site 3. This model is consistentwith the lithology and foraminiferal content, and would constraintiming to an interval (late MIS3a) when water depth was ~−30 m onthe NJ shelf. Site 3 Unit Cmay have been deposited as amixture of erod-ed, shallow water, estuarine sediments with in situ middle shelf muds.A reinvigorated paleo-Hudson River during interstadial MIS 3a couldhave provided the energy required for transport (Carey et al., 2005).The hornblende date in Unit 3C is the same age as a sample recoveredfrom Site 1 Unit C (MIS 3) (Table 5), so the MIS3 sediments all seemto have come from the same source.

4.4. Sediment sources, Paleo-Hudson River system

Analysis of hornblende ages provides insight into origin of a portionof the shelf sediments, and thus potential transport pathways from thecontinent. Turner (2005) has analyzed three sets of hornblende crystalsat Sites 1 and 3 that fall into two clusters of ages (Table 5). Sheinterpreted this as a mixture of the two major sources of hornblendeto the NJ shelf: Grenvillian rocks of the Hudson River drainage basinand NJ Highlands (1000–915 Ma), and younger, Paleozoic rocks of theCortland, Rosetown, and Stony Point complexes (430 Ma) found northof New York City (NYC, Fig. 1). Thus, non-marine sediments on the NJshelf come from two regions: 1) the PrecambrianNJ Highlands/ReadingProng, and 2) the Hudson River (Fig. 1).

One set of hornblende grain ages [850–880 KA (Site 1, Unit B; Site 3,Unit F)] is associated with sediments deposited during MIS6-3 and an-other [930–960 ka (Site 1, Unit A; Site 3, Units A, B)] is associatedwith sediments deposited post-LGM (Table 5; Figs. 3 and 7). Thus, thetwoK–Ar age groupings suggest delivery to the study area from two dif-ferent source areas, or amixture of source areas. The hornblende assem-blage associated with the post-LGM sediments have the oldest ages,and have been interpreted as weathered from Grenvillian basement(Turner, 2005). They are consistent with NJ Highlands and the ReadingProng emplacement ages of 915 to >1000 Ma (Gates et al., 2003).

The assemblages associated with MIS 6–3, lower in the section, haveyounger hornblende ages, and are interpreted as amixture of Grenvillianbasement and younger crystals. There are no rocks in the potential sourceregions that match the age of hornblendes found in the MIS3-aged shelfsediments; an allochthonous glacial origin is possible. Regional sourcesfor younger hornblende crystals are located ~55 km north of NYC alongthe Hudson River. These Paleozoic intrusions include the Cortlandcomplex (420 Ma) and Rosetown pluton (463+10 Ma; 483+10 Ma)(e.g., Dallmeyer, 1975). The other set of local, extrusive rocks, theMesozoic units of NJ (Orange Mountain, Preakness, and Hook Mountain)are not hornblende-rich. However, only ~15% of the young materialwould need to be mixed with the Grenvillian NJ and Hudson High-lands material to arrive at the ages found in the lower part of Sites 1and 3 [(875 Ma=15% Paleozoic rocks (~450 Ma)+85% Grenvillian(~950 Ma)].

The two hornblende assemblages suggest a change in source ofsediment to the study region before and after the last glaciation.The mixed MIS3–aged samples suggest that sediments were deliv-ered to the study area by the paleo-Hudson River (Fig. 1). Thepost-LGM assemblage indicates a lesser or no contribution from thelower Hudson drainage system, or conversely, an even greater contri-bution from the NJ/Hudson Highlands region. The paleo-HudsonRiver had switched to an approximation of its modern position bythe time the post-LGM sediments were deposited (Knebel et al.,1979), allowing for delivery of sediment to the shelf by NJ rivers. It

is possible that the change in hornblende crystal assemblage resultedfrom the enhanced input from these rivers (e.g., paleo-Raritan orpaleo-Mullica) during the period of shelf exposure. Previous studieshave demonstrated an increased significance in the paleo-Raritanfor sediments deposited west of the Hudson Canyon/Hudson Shelfsystem (McHugh et al., 2010). The orientation of fluvial features iden-tified by Nordfjord et al. (2005) (Fig. 5) suggests a NJ shelf drainagesystem dominated during MIS 2 and 1 by a hinterland source otherthan the Hudson River, perhaps another river system to the south.

5. Summary and analysis of Sites 1–3

By ground-truthing high resolution CHIRP seismic reflection profileswith continuous core, we have been able to identify six latest Pleisto-cene sedimentary intervals on the mid-to outer NJ shelf (Fig. 5):1) pre-R deposition; 2) formation of R, 3) exposure and redepositionforming the OSW and DSW, 4) continued shelf exposure and incision/downcutting associated with final glaciation, 5) infilling associatedwith the last post-glacial sea-level rise, and 6) formation of a Holocenemobile sand veneer. These intervals were formed in MIS 6 or 4 (earlypre-R deposition), MIS 3 (latest part of pre-R deposition, R formation),around the MIS3/2 boundary (shelf exposure and formation of OSWand DSW), duringMIS2 (continued shelf exposure and presumed fluvi-al incision/downcutting), late MIS 2 (infilling), and MIS1 (Holoceneveneer).

5.1. MIS 6 or MIS 4 sedimentation

Deposition of Site 3 (75 m w.d.), Unit F occurred prior to ~40 ka.The high degree of induration suggests deposition either during MIS4, when the lower sea level, about−75 m (Fig. 5), brought the coast-line near the study area, or even earlier, during MIS 6, although sealevel during MIS 6 would have placed the coastline far landward ofSite 3 (Fig. 5; Wright et al., 2009). Deposition during MIS 4 is in agree-ment with the limited subsidence (~5 m) estimated for MIS 4 byWright et al. (2009). Furthermore, high rates of subsidence duringMIS 4 would predict the presence of similarly aged sediments onthe slope, but nearby ODP Sites 902–904 lack sediments from MIS4–2 (Christensen et al., 1996), indicating non-deposition/sedimentby-pass, and/or mass wasting related to eustacy and sediment insta-bility (e.g., McHugh et al., 2002). Water depth at Site 3 would alsobe consistent with deposition during a stadial within MIS 5.

5.2. MIS 3 sedimentation

Formation of R began as sea level fell in MIS3b and continued intoMIS3a. Gulick et al. (2005) have proposed that the sediments of theouter NJ shelf were deposited in MIS3 and then subsequently eroded,reworked and redeposited as the OSW and DSW as sea level fell priorto the LGM. Their model explains the overall geometry of the regionand the mixed foraminiferal assemblages. However, the nearbypaleo-Hudson River may also have played a role (Figs. 1 and 5).Carey et al. (2005) have mapped a mid-shelf (paleo-Hudson) channelduring MIS4 that was bisected in MIS 3b by a change in orientation ofthat channel (Fig. 5). This new channel would have provided abun-dant sediment to the study area from an estuarine (paleo-Hudson)environment, consistent with the observed stained foraminifera andiron nodules found in samples of this age. The paleo-Hudson Rivercould have fed a MIS3b/early MIS3a deltaic system in the vicinityof the study area (Fig. 5). Furthermore, the internal geometry ofthe crossing seismic profile (Fig. 3) suggests a delta front- theshallow-water inner shelf deposits (Site 1, Unit D) have a planar ori-entation. As sea level rose into MIS3a, fluvial flow would have beenreduced, and the study area would have returned to a more marineenvironment. In MIS 3a, tilted strata were deposited (Unit 1C),reflecting a more distal position from the river mouth. Limited


carbonate (shell and foraminifera) is also consistent with rapid delta-ic sedimentation, as these depositional settings often have a depau-perate fauna.

5.3. MIS3a to 3/2 boundary (30–24 ka)

Deposition of sediments during this period occurred at Site 1 (UnitB) in an inner-middle shelf environment likely coeval with incision atsites 2 and 3 (Fig. 5). However, it is not possible to determine theexact timing of incision at those sites from the stratigraphy alone.At Site 1, estimates for sea level at 30 Ka are around−75 m, and clos-er to −100 m by ~25 ka (Fig. 5). Sea levels would have been lowerthan at sites 2 and 3 by ~25 ka, leaving them subaerial at this time.Sea level fall would have exposed much of the shelf, but, assuming lit-tle or no flexural response from changes in ice load (Wright et al.,2009), sea level was still high enough at Site 1 to accommodate ma-rine sedimentation there, and therefore allow development of theOSW and DSW through either a deltaic sedimentation mechanismor as proposed by Gulick et al. (2005).

5.4. Early MIS 2 to LGM

Regional fluvial/subaerial incision of the NJ shelf was driven by amajor sea level fall (to−120 m) in MIS2. The exact timing is uncertainin our study area, but McHugh et al. (2010) place the most seawardshoreline at 17 ka north of the Hudson Canyon. Channels were cutinto sediments ofMIS 3 age at Sites 2 and 3 (Figs. 5, 6, and 7), as predict-ed byNordfjord et al. (2006). No sediments of this age are recognized atSite 1, indicating either a lack of accommodation space or subsequenterosion. The channels formed around the time of the LGMwere infilledas deglaciation proceeded and sea- level began to rise across the ex-posed shelf. The infilled channels mapped by Nordfjord et al. (2005),northwest of Site 1 and northeast of Site 3, are interpreted as fluvial in-cision systems associatedwith glacial regression on the basis of channelmorphology and orientations. Nordfjord et al. (2005) also constraindowncutting to between the LGMand15Ka,when seismically observedchannel-lag sediments were deposited. No shell material dated be-tween the ages of 30 and 16 ka was recovered at Sites 1, 2 or 3.

5.5. Late MIS 2 (post-LGM) and meltwater pulse 1A

Site 2 received large volumes of sediment (~10 m; 1112 – 35 cm,units C and B) in a very short period of time (~2 k.y.) (Fig. 6). Theinfill of the seismically observed channel reveals multiple phases of de-position and suggests slumping and soft sediment deformation at thechannel flanks, away from the area that was cored. There are limiteddata available for Site 3 channel infill, but careful examination of theleft-hand portion of the complex channel (Fig. 7) suggests a second de-positional unit within the infill, much like that found at Site 2 (Fig. 6).After incision, sediments could have moved through this channel, butthe very low sea levels in the area at that time (~0 m w.d.) wouldhave limited accommodation space and preventedmuch accumulation.At ~15 ka, sea-level rise permitted accumulation of thicker sedimentarysequences in these channels (1077 cm in b2000 yr). Nordfjord et al.(2006) predict a sequence of infilling that begins with estuarine flankdeposits associated with the post-LGM transgression. Although our es-tuarine/shallow marine interpretation is consistent with their model,we are not able to resolve paleoenvironmental differences in enoughdetail to test their infilling scenario. There is also agreement with thetiming of events determined by McHugh et al. (2010), although thatstudy finds widespread deposition from 15 to 11 ka. We attribute thedifferences to regional variations in subsidence and sediment supply.

Meltwater from the Laurentide Ice Sheet apparently did have adramatic effect on the region. A catastrophic deglacial sedimentaryresponse known as a jökulhlaup has been proposed to explain bothsignificant erosional features and interpreted depositional lobes in

the vicinity of the Hudson Canyon at 13,350 years B.P. (Uchupiet al., 2001; Donnelly et al., 2005). The meltwater release is thoughtto have initiated the Intra-Allerød cold period, a b400 yr-long intervalof reduced thermohaline strength (Donnelly et al., 2005). However,the timing of the jökulhlaup (13,400 – 13,100 y BP; Donnelly et al.,2005) is later than the time of deposition at Site 2, as indicated byboth shell (16,365+350 to 14,979+930 cal yr BP) and wood(14,198+200 to 14,139+210 yr BP). Furthermore, although theinfill rates are high for pelagic processes (excluding turbidites), thesedimentation rates of 0.5–1 cm/yr at Site 2 are not unusual for mod-ern fluvial and estuarine systems. Rather than meltwater, a more like-ly explanation is that an increase in accommodation space related tosea level rise drove infill of seismically observed incisions, as has alsobeen postulated by Duncan et al. (2000) and Nordfjord et al. (2005).Similarly high rates of deposition are found on the slope (e.g., ODPSite 1073 MIS 2 rates are >300 cm/ky, e.g., McHugh and Olson,2002; Mountain et al., 2007), although Site 1073 sits north of thehinge line defined by Dillon and Oldale (1978) and may have benefit-ed from increased rates of post-glacial subsidence. McHugh et al.(2010) find possible evidence that the jökulhlaup was confined tothe Hudson Canyon- incision into the Hudson Canyon floor- butdeem that evidence inconclusive.

However, the infilling was coeval with meltwater pulse 1A(MWP-1A, see Fig. 5; ~14,600 yr BP; Fairbanks, 1989). Estimates forthe rapid global sea level resulting from MWP-1A are as high as~20 m over 500 yrs (Weaver et al., 2003). Stanford et al. (2010)place MWP-1A between 14.3 kyr BP and 12.8 kyr BP, with a maxi-mum rate of rise at 13.8 ka. The sea-level rise associated withMWP-1A could have led to channel infilling by shifting the coastlinelandward of the study area. That would have provided enough ac-commodation space to preserve sediments, first at Site 2 and thenat Site 3 (Fig. 5). The timing of infill sedimentation in Site 2 and bycorrelation, Site 3, is in agreement with the model of Nordfjordet al. (2005) for the nature of formation of these buried channels.The channel infill episode is a unique stratigraphic window into pro-cesses associated with deglaciation.

5.6. MIS 1 (Holocene sand sheet)

Following the infill of the channels at the end of MIS2 and the con-tinuing landward shift in shoreline, sea level kept rising, but at a slowerrate. A second increase in the rate of sea level rise (MWP-1B) occurredbetween 11.5 and 8.8 ka (Stanford et al., 2010),whichmoved the coast-line farther landward and led to Holocene deposition. The Holocenesand veneer is present at all three of our sampling locations in varyingthicknesses, but is slightly thicker on the outer shelf (Site 1: 64 cm,Site 2: 35 cm, Site 3: 45 cm) (Figs. 3, 6, and 7). This mobile sand sheetcontains a high percentage of Cibicicoides spp., many of which areabraded, indicating a relict population that is transported along withnon-biogenic sediment grains. The transition from channel infillingand estuarine/nearshore conditions to more modern shelf conditionsoccurred during this time, when sea level would have been within~20 m of its modern depth (Fig. 5). This is in contrast to the deposition-al regime north of the Hudson Canyon, which has received little sedi-ment since 11 ka (McHugh et al., 2010).

6. Conclusions

Our results are in general agreement with the best available NJ sealevel curve (Wright et al., 2009; Fig. 5), and indicate that no significantsubsidence has impacted the study area during at least the last glacialcycle. Differences in sediment thickness between our sites and thosefarther north of the hinge line (e.g., ODP 1073), alongwith compositionand timing (McHugh et al., 2010), suggest that subsidencemay bemoreof a factor approaching the Hudson Canyon. During MIS3, sea level wassignificantly lower, and the study area was influenced by estuarine/


inner shelf processes. Our mixing model indicates a younger source ofsediments derived from the Hudson River region was delivered to thestudy area. This is consistent with amid-shelf paleo-Hudson River posi-tion within our study area, as postulated by Carey et al. (2005).

Our results indicate the unconformity R was formed around the MIS3b sea level low, ~45 ka. Deposition of the OSW occurred through eithera deltaic model or under a forced regression, thewedge system proposedby Gulick et al. (2005), but the foraminiferal, textural and radiocarbondata are insufficient to point to a specific model. The data are also consis-tent with the H3 ice scour event proposed by Goff and Austin (2009).

The sea-level fall associated with latest MIS 3 and into MIS 2 resultedin non-deposition and/or subaerial erosion at Sites 2 and 3, and there areno sediments at any of our sites of LGM age. The exposure surfacewas re-gionally extensive, and has also been mapped north of the HudsonCanyon area (McHugh et al., 2010). The channels excavated during thesea level lowweremodified during the post-LGM sea- level rise and sub-sequent infilling. From LateMIS 2 intoMIS 1, deposition began again at allsites, as sea level transgressed the shelf. Fluvial infilling began ~16 ka atSite 2 and occurred rapidly in an estuarine to inner-shelf environment.Smaller-scale changes in environment occurred locally as the fluvialchannels were infilled in less than 2000 yr. Preservation of channel infillwas promoted by the rapid MWP-1A sea-level rise. There is no evidencein our study area for a jökulhlaup associated with the subsequentIntra-Allerød cold period at ~13,350 yr BP (Donnelly et al., 2005).

During late MIS2 (LGM) and MIS1, hinterland sediments were pri-marily derived from the Reading Prong (NJ Highlands/Hudson) and de-livered by NJ rivers. This is in agreement with the model of Nordfjord etal. (2006),which shows that themajor river systems (Hudson, Delaware)were reduced in significance. The region is generally overlain by apalimpsest, mobile sand unit with shell material deposited during MIS1.

Our study combines continuous, long cores obtained using theAHC-800 with detailed seismic images at the same scale as the litho-logic changes. The ability to ground truth inferred lithologic changesfrom seismic data with sediment from the NJ margin makes thisstudy valuable and unique. Our analysis has used foraminiferal andsedimentological data to reconstruct fluvial channel infilling andother depositional events during transgression, 14C dates to deter-mine timing of these events, and K–Ar dating on hornblende crystalsto determine sediment sources. This combination of techniques anddata has allowed us to begin to unravel the complex pattern of inter-actions on the latest Pleistocene NJ shelf.

Acknowledgements

This work was supported by the Office of Naval Research awardsN00014-02-1-0245, N00014-04-1-0035 and N00014-04-1-0036 as partof the Geoclutter Initiative. The authors would like to thank colleagues,technicians and students from Skidaway Institute of Oceanography, Uni-versity of Delaware, University of Texas Institute for Geophysics, theUSGS for assisting in core collection and sampling, and the crew of theR/V Knorr and DOSECC team for their hard work collecting the core. Weacknowledge Claudia Venherm for hermajor role in post-cruise samplingand in grain size analysis and Sylvia Nordfjord for generation of theCHIRP images. Christensen would also like to thank Suzanne O'Connelland MaryAnne Holmes for the opportunity to participate in the GAINwriting retreat supported by the Advance Grant Program, NSF 0620101and 0620087. Insightful comments by GregMountain and an anonymousreviewer greatly improved the manuscript. Finally, the authors wouldlike to thank the Integrated Ocean Drilling Program for maintaining andarchiving these cores in their collection. UTIG contribution # 2542.

References

Alexander, C., Austin, J.A., 2002. AHC-800 Coring on the New Jersey Shelf for ONR'sGeoclutter Iniative. Cruise Report- KN 167-168A/B, R/V Knorr, September 27–October17, 2002, Woods Hole, MA–Woods Hole, MA (25 pp.).

Allen, G.P., Posamentier, H.W., 1993. Sequence stratigraphy and facies model of anincised valley fill: the Gironde Estuary, France. Journal of Sedimentary Petrology 63,378–391.

Ashley, G.M., Wellner, R.W., Esker, D., Sheridan, R.E., 1991. Clastic sequences developedduring late Quaternary glacio–eustatic sea-level fluctuations on a passive conti-nental margin: example from the inner continental shelf near Barnegat Inlet,New Jersey. Geologic Society of America Bulletin 103, 1607–1621.

Austin Jr., J.A., Christie-Blick, N., Malone, M.J., et al., 1998. Proceedings of the OceanDrilling Program, Initial Reports, 174A. Ocean Drilling Program, College Station,TX. http://dx.doi.org/10.2973/odp.proc.ir.174a.1998.

Björck, S., Walker, M.J.C., Cwynar, L.C., Johnsen, S., Knudsen, K.-L., Lowe, J.J., Wohlfarth,B., 1998. An event stratigraphy for the last termination in the North Atlantic regionbased on the Greenland icecore record: a proposal by the INTIMATE group. Journalof Quaternary Science 13, 283–292.

Browning, J.V., Miller, K.G., McLaughlin, P.P., Kominz, M.A., Sugarman, P.J., Monteverde,D., Feigenson, M.D., Hernandez, J.C., 2006. Quantification of the effects of eustasy,subsidence, and sediment supply on Miocene sequences, U.S. Mid-Atlantic Margin.Geological Society of America Bulletin 118, 567–588.

Browning, J.V., Miller, K.G., Sugarman, P.J., Kominz, M.A., McLaughlin, P.P., Kulpecz, A.A.,2008. 100 Myr record of sequences, sedimentary facies and sea-level change fromOcean Drilling Program onshore coreholes, U.S. Mid-Atlantic coastal plain. BasinResearch 20, 227–248.

Buck, K.S., Olson, H.C., Austin Jr., J.A., 1999. Paleoenvironmental evidence for latestPleistocene sea-level fluctuations on the New Jersey outer continental shelf: com-bining high-resolution sequence stratigraphy and foraminiferal analysis. MarineGeology 154, 287–304.

Carey, J.S., Sheridan, R.E., Ashley, G.M., Uptegrove, J., 2005. Glacially-influenced latePleistocene stratigraphy of a passive margin: New Jersey's Record of the NorthAmerican ice sheet. Marine Geology 218, 155–173.

Christensen, B.A., Hoppie, B.W., Thunell, R.C., Miller, K.G., Burckle, L., 1996. Pleistoceneage models. In: Mountain, G.S., Miller, K.G., Blum, P. (Eds.), Proceedings of theOcean Drilling Program, Scientific Results, vol. 150. U. S. Govt. Printing Office,Washington.

Culver, S.J., Snedden, J.W., 1996. Foraminiferal implications for the formation of NewJersey shelf sand ridges. Palaios 11, 161–175.

Dallmeyer, R.D., 1975. 40Ar/39Ar spectra of biotite and hornblende from the Cortlandtand Rosetown plutons, New York, and their regional implications. Journal of Geology83 (5), 629–643.

Dalrymple, R.W., Zaitlin, B.A., Boyd, R., 1992. Estuarine facies models: conceptualbasis and stratigraphic implications. Journal of Sedimentary Petrology 62,1130–1146.

Davies, T.A., Austin Jr., J.A., Lagoe,M.B.,Milliman, J.D., 1992. Late Quaternary sedimentationoff New Jersey: new results using 3-D seismic profiles and cores. Marine Geology 108(3–4), 323–343.

Dillon, W.P., Oldale, R.N., 1978. Late Quaternary sea-level curve: reinterpretation basedon glacio–tectonic influence. Geology 6, 56–60.

Donnelly, J.P., Driscoll, N.W., Uchipi, E., Keigwin, L.D., Schwab, W.C., Thieler, E.R., Swift,S.A., 2005. Catastrophic meltwater discharge down the Hudson Valley: a potentialtrigger for the Intra-Allerød cold period. Geology 33, 89–92.

Duncan, C.S., 2001. Late Quaternary stratigraphy and seafloor morphology of the NewJersey Continental Shelf, PhD Thesis, University of Texas, p. 222.

Duncan, C.S., Goff, J.A., Austin, J.A., Fulthorpe, C.S., 2000. Tracking the last sea levelcycle: seafloor morphology and shallow stratigraphy of the latest quaternaryNew Jersey middle continental shelf. Marine Geology 170, 395–421.

Fairbanks, R.G., 1989. A 17,000-year glacio-eustatic sea level record influence ofglacialmelting rates on the Younger Dryas event and deep-ocean circulation. Nature342, 637–642.

Fulthorpe, C.S., Austin Jr., J.A., 2004. Shallowly buried, enigmatic seismic stratigraphyon the New Jersey mid-outer shelf: evidence for latest Pleistocene catastrophicerosion? Geology 32, 1013–1016.

Gates, A.E., Valentino, D.W., Gorring, M.L., Chiarenzelli, J.R., Hamilton, M.A., 2003. Fieldtrip to the western Hudson Highlands. Long Island Association of ProfessionalGeologists, New York. (http://pbisotope.ess.sunysb.edu/lig/Field_Trips/index.htm).

Gevirtz, J.L., Park, R.A., Friedman, G.M., 1971. Paraecology of benthonic foraminiferaand associated microorganisms on the continental shelf off Long Island, New Yotk.Journal of Paleontology 45, 153–177.

Goff, J.A., Austin, J.A., 2009. Seismic and bathymetric evidence for four differentepisodes of iceberg scouring on the New Jersey outer shelf: Possible correlationto Heinrich events. Marine Geology 266, 244–254.

Goff, J.A., Austin, J.A., Gulick, S.P.S., Nordfjord, S., Christensen, B., Sommerfield, C.K.,Olson, H.C., Alexander, C.R., 2005. Recent and modern marine erosion on theNew Jersey outer shelf. Marine Geology 216, 275–296.

Gulick, S.P.S., Goff, J.A., Austin, J.A., Alexander, C.R., Nordfjord, S., Fulthorpe, C.S., 2005.Basal inflection-controlled shelf-edge wedges off New Jersey track sea-level fall.Geology 33, 429–432.

Hathaway, J.C., Poag, C.W., Valentine, P.C., Miller, R.E., Schultz, D.M., Manheim, F.T.,Kohout, F.A., Bothner, M.H., Sangrey, D.A., 1979. US Geological Survey core drillingon the Atlantic shelf. Science 206, 515–527.

Katz, M., Miller, K.G., Mountain, G.S., 2003. Biofacies and lithofacies evidence forpaleoenvironmental interpretations of upper Neogene sequences on the New Jerseycontinental shelf (ODP Leg 174A). Micropaleontologic Proxies for Sea-Level Changeand Stratigraphic Discontinuities: Society for Sedimentary Geology (SEPM) SpecialPublication No. 75.

Keith, M.L., Anderson, G.M., Eichler, R., et al., 1964. Carbon and oxygen isotope compo-sition of mollusk shells from marine and fresh-water environments. Geochimica etCosmochimica Acta 28, 1757–1786.

http://dx.doi.org/10.2973/odp.proc.ir.174a.1998

http://pbisotope.ess.sunysb.edu/lig/Field_Trips/index.htm


Knebel, H.J., Spiker, E., 1977. Thickness and age of surficial sand sheet, Baltimore canyontrough area. American Association of Petroleum Geologists Bulletin 61, 861–871.

Knebel, H.J., Wood, S.A., Spiker, E.C., 1979. Hudson river: evidence for extensive migra-tion on the exposed continental shelf during pleistocene time. Geology 7, 254–258.

Kominz, M.A., Browning, J.V., Miller, K.G., Sugarman, P.J., Misintseva, S., Scotese, C.R.,2008. Late Cretaceous to Miocene sea-level estimates from the New Jersey andDelaware coastal plain coreholes: an error analysis. Basin Research 20, 211–226.

Kulpecz, A.A., Miller, K.G., Sugarman, P.J., Browning, J.V., 2008. Subsurface distributionof Upper Cretaceous sequences and facies, New Jersey Coastal Plain. Journal ofSedimentary Research 78, 112–129.

Lagoe, M.B., 1994. Radiocarbon results: National Ocean Sciences AMS facility. Data Report94–114 (12 pp.).

Lagoe, M., Davies, T.A., Austin, J.A., Olson, H.C., 1997. Foraminiferal constraints on very high-resolution seismic stratigraphy and late Quaternary glacial history, New Jersey conti-nental shelf. Palaios 12, 249–266.

Loeblich Jr., A.R., Tappan, H., 1953. Studies of Arctic foraminifera. SmithsonianMiscellaneousCollections 121, 1–150.

Matoba, Y., Fukasawa, K., 1992. Depth distribution of Recent benthicforaminifera onthe continental shelf and uppermost slope off southern Akita prefecture, northeastJapan (the eastern Japan Sea). In: Ishizaki, K., Saito, T. (Eds.), Centenary of JapaneseMicropaleontology. Terra Scientific Publishing Co., Tokyo, pp. 207–226.

McHugh, C.M.G., Olson, H.C., 2002. Pleistocene chronology of continentalmargin sedimenta-tion: new insights into traditional models, New Jersey. Marine Geology 186, 395–417.

McHugh, C.M.G., Damuth, J.E., Mountain, G.S., 2002. Cenozoic mass-transport facies andtheir correlation with relative sea-level change, New Jersey continental margin.Marine Geology 184, 295–334.

McHugh, C.M.G., Hartin, C.A., Mountain, G.S., Gould, H.M., 2010. The role of glacio-eustasyin sequence formation: Mid-Atlantic Continental Margin, USA. Marine Geology 227,31–47.

Miller, K.G., Browning, J.V., Sugarman, P.J., et al., 2002. 174AX leg summary: sequences,sea level, tectonics, and aquifer resources: coastal plain drilling. In: Miller, K.G.,Sugarman, P.J., Browning, J.V., et al. (Eds.), Proceedings of theOceanDrilling Program, Ini-tial Reports, 174AX. Ocean Drilling Program, College Station TX, pp. 1–40 (Supplement).

Miller, K.G., Kominz, M.A., Browning, J.V., Wright, J.D., Mountain, G.S., Katz, M.E.,Sugarman, P.J., Cramer, B.S., Christie-Blick, N., Pekar, S.F., 2005. The Phanerozoicrecord of global sea-level change. Science 310, 1293–1298.

Miller, K.G., Browning, J.V., Mountain, G.S., Sheridan, R.E., Sugarman, P.J., Glenn, S.,Christensen, B.A., in press. Continental shelf sedimentation on the Middle AtlanticU.S. margin: Evaluating the last glacioeustatic cycle with a 100 Myr perspective.Geological Society of London Special Publication.

Milliman, J.D., Jiezao, Z., Anchun, L., Ewing, J.I., 1990. Late quaternary sedimentation onthe outer and middle New Jersey continental shelf: result of two local deglacia-tions? Journal of Geology 98, 966–976.

Mountain, G.S., Burger, R.L., Delius, H., Fulthorpe, C.S., Austin, J.A., Goldberg, D.S.,Steckler, M.S., McHugh, C.M., Miller, K.G., Monteverde, D.H., Orange, D.L., Pratson, L.F.,2007. The Long-Term Stratigraphic Record on Continental Margins - The long-term re-cord. In: Nittrouer, C.A., Austin Jr., J.A., Field, M.E., Kravitz, J.H., Syvitski, J.P.M.,Wiberg, P.L. (Eds.), Continental Margin Sedimentation: From Sediment Transportto Sequence Stratigraphy. IAS Special Publication No. 37. Blackwell Publishing Ltd.,Oxford, pp. 381–458.

Nielson, D.L., Pardey, M., Austin, J.A., Goff, J.A., Alexander, C., Christensen, B.A., Gulick,S.P., Fulthorpe, C.S., Nordfjord, S., Sommerfield, C., Venherm, C., 2003. ActiveHeave-Compensated Coring On The New Jersey Shelf. Eos Transactions, AmericanGeophysical Union 84 (46) (Fall Meet. Supplement, Abstract OS52B-0908).

Nordfjord, S., Gulick, S.P., Austin Jr., J.A., Goff, J.A., Fulthorpe, C.S., 2002. Late QuaternaryIncisions and Related Shallow Subsurface Stratigraphy on the New Jersey Mid-OuterShelf: Preliminary Results from Ultra-High Resolution Chirp Sonar Images—Part I.Eos Transactions, American Geophysical Union 83 (Fall Meeting Supplement,Abstract OS71C-0299).

Nordfjord, S., Goff, J.A., Austin, J.A., Sommerfield, C.K., 2005. Seismic geomorphology ofburied channel systems on the New Jersey outer shelf: Assessing past environmen-tal conditions. Marine Geology 214, 339–364.

Nordfjord, S., Goff, J.A., Austin, J.A., Gulick, S.P.S., 2006. Seismic facies of incised-valleyfills, New Jersey continental shelf: Implications for erosion and preservationprocesses acting during latest Pleistocene-Holocene transgression. Journal ofSedimentary Research 76, 1284–1303. http://dx.doi.org/10.2110/jsr2006.108.

Parker, F.L., 1948. Foraminifera of the continental shelf from the Gulf of Maine toMaryland. Harvard University, Museum of Comparative Zoology, Bulletin 100,213–241.

Pekar, S.F., Christie-Blick, N., Miller, K.G., Kominz, M.A., 2003. Quantitative constraintson the origin of stratigraphic architecture at passive continental margins: Oligocenesedimentation in New Jersey, U.S.A. Journal of Sedimentary Research 73, 227–245.

Poag, C.W., 1981. Ecologic Atlas of Benthic Foraminifera of the Gulf of Mexico.Hutchinson Ross Publishing Co., Stroudsburg, Pennsylvania . (174 pp.).

Poag, C.W., Knebel, H.J., Todd, R., 1980. Distribution of modern benthic foraminifers onthe New Jersey outer continental shelf. Marine Micropaleontology 5, 43–69.

Stanford, J.D., Hemingway, R., Rohling, E.J., Challenor, P.G., Medina-Elizalde, M., Lester,A.J., 2010. Sea-level probability for the last deglaciation: A statistical analysis offar-field records. Global and Planetary Change 79 (3–4), 193–203.

Stubblefield, W.L., McGrail, D.W., Kersey, D.G., 1984. Recognition of transgressive andpost-transgressive sand ridges on the New Jersey continental shelf. In: Tillman,R.W., Siemers, C. (Eds.), Siliciclastic Shelf Sediments. Society of Economic Paleon-tologists and Minerologists, Tulsa, pp. 1–23.

Stuiver, M., Reimer, P.J., 1993. Extended 14C data base and revised CALIB 3.0 14C agecalibration program. Radiocarbon 35, 215–230.

Stuiver, M., Reimer, P.J., Reimer, R.W., 2005. CALIB 6.0. [WWW program and documen-tation]. http://calib.qub.ac.uk/calib/.

Swift, D.J.P., Field, M.E., 1981. Evolution of a classic sand ridge field: Maryland sectorNorth American inner shelf. Sedimentology 28, 461–482.

Swift, D.J.P., Kofoed, J.W., Saulsbury, F.P., Sears, P., 1972. Holocene evolution of the shelfsurface, central and southern Atlantic shelf of North America. In: Swift, D.J.P.,Duane, D.B., Pilkey, O.H. (Eds.), Shelf Sediment Transport: Process and Pattern.Dowden, Hutchinson & Ross, Stroudsburg, Penn, pp. 499–574.

Turner, R.J., 2005, Provenance and depositional history of late Pleistocene New Jerseyshelf sediments. Unpublished Masters thesis, Georgia State University.

Uchupi, E., Driscoll, N., Ballard, R.D., Bolmer, S.T., 2001. Drainage of late Wisconsinglacial lakes and the morphology and late quaternary stratigraphy of the New Jersey–Southern New England continental shelf and slope. Marine Geology 172, 117–145.

Weaver, J.A., Saenko, O.A., Clark, P.U., Mitrovica, J.X., 2003. Meltwater Pulse 1A fromAntarctica as trigger of the Bølling-Allerød Warm Interval. Science 299 (5613),1709–1713. http://dx.doi.org/10.1126/science.1081002.

Wright, J., Sheridan, R., Miller, K.G., 2009. Late Pleistocene Sea level on the New JerseyMargin: Implications to Eustasy and Deep-sea Temperature. Global and PlanetaryChange 66 (1–2), 93–99.

Zaitlin, B.A., Dalrymple, W., Boyd, R., 1994. The stratigraphic organization of incised-valley systems associated with relative sea-level change. In: Dalrymple, R.W.,Boyd, R., Zaitlin, B.A. (Eds.), Incised-Valley Systems: Origin and SedimentarySequences: SEPM, Special Publication, 51, pp. 45–60.

http://dx.doi.org/10.2110/jsr2006.108

http://calib.qub.ac.uk/calib/

http://dx.doi.org/10.1126/science.1081002

the last glacial: insights from continuous coring on the new jersey continental shelf

Documents