39. GEOLIPID COMPARISON OF BIOGENIC SEDIMENTS FROM DEEP SEA DRILLINGPROJECT HOLES 530B, ANGOLA BASIN, AND 532, WALVIS RIDGE1

Philip A. Meyers and Keith W. Dunham, Oceanography Program, Department of Atmospheric and OceanicScience, The University of Michigan, Ann Arbor, Michigan

ABSTRACT

Distributions of free and bound n-alkanes, n-alkanoic acids, and n-alkanols were determined in order to comparethe character of organic matter contained in organic-carbon-rich sediments from two sites sampled by the hydraulic pis-ton corer. Two diatomaceous debris-flow samples of Pleistocene age were obtained from Hole 53OB in the Angola Ba-sin. A sample of bioturbated Pleistocene diatomaceous clay and another of bioturbated late Miocene nannofossil claywere collected from Hole 532 on the Walvis Ridge. Geolipid distributions of all samples contain large terrigenous con-tributions and lesser amounts of marine components. Similarities in organic matter contents of Hole 53OB and Hole532 sediments suggest that a common depositional setting, probably on the Walvis Ridge, was the original source ofthese sediments through Quaternary, and possibly late Neogene, times and that downslope relocation of these biogenicdeposits has frequently occurred.

INTRODUCTION

Most deep-sea sediments contain less than 0.2% or-ganic carbon (Degens and Mopper, 1976), suggestingthat the circumstances favoring accumulation and pres-ervation of organic matter in the ocean bottom rarelyoccur. However, factors such as high rates of primaryproduction, enhanced sinking rates of detritus, an ex-panded oxygen minimum zone, and high sedimentationrates, all of which are found in upwelling areas, cancombine to allow large concentrations of organic matterto accumulate in oceanic sediments. Such organic mate-rial represents the residue of organisms formed by bio-synthesis in the photic zone of the highly productiveoverlying waters, augmented by land-derived biologicaldetritus transported to ocean basins by water movementand winds.

Upwelling systems provide optimized situations forthe investigation of organic matter inputs to sedimentsbecause underlying sediments contain sufficiently highconcentrations of biogenic matter to permit detailedanalyses of temporal fluctuations in input rates andcharacter. It is evident, however, that even under upwell-ing areas, such as the Benguela Current system offshoreof southwest Africa, the appearance of the circum-stances favoring organic matter accumulation is epi-sodic.

Several locations under the offshore edge of the Ben-quela Current have been sampled as part of the DeepSea Drilling Project/International Phase of Ocean Drilling(DSDP/IPOD). Erdman and Schorno (1978) report or-ganic carbon concentrations as high as 7.2% in uppersections of sediments obtained from Site 362 by rotarydrilling during DSDP Leg 40. Based upon concentra-tion patterns of organic carbon, diatom abundances,and nutrient incorporation in these sediments, a late

' Hay, W. W., Sibuet, J.-C, et al.. Init. Repts. DSDP, 75: Washington (U.S. Govt. Print-ing Office).

Miocene onset of upwelling has been proposed by Dies-ter-Haass and Schrader (1979) and Seisser (1980). Ship-board organic carbon data from Sites 530 and 532 cor-roborate with those from Site 362 (Hay et al., 1982;Meyers, Brassell, and Hue, this volume).

Sediments from Hole 530B in the Angola Basin con-sist of turbidites and debris-flow deposits, presumablyoriginating from biogenic oozes originally laid down onthe Walvis Ridge. The sediments at Site 532 on theWalvis Ridge are made up of alternating sequences oflight and dark pelagic oozes and are heavily biotur-bated. The dark layers are richer in organic carbon, clayand pyrite (Hay et al., 1982). A possible explanation forthis pattern is episodic increases in wind-driven marineproductivity, creating relative increases in organic mat-ter inputs and sedimentation rates. The increased claycomponent of the dark layers may be the result of an in-creased eolian input of continental material.

Based upon general similarities in microfossils, sedi-ment texture, and organic matter character, Hay et al.(1982) concluded that Miocene and younger sedimentsat Site 530 in the Angola Basin represent relocated mate-rial which was originally deposited on the Walvis Ridge.Meyers, Brassell, and Hue (this volume) give concentra-tions of organic carbon and C/N ratios of organic mat-ter of Neogene and Quaternary samples from Sites 530and 532. The values are quite similar in both the turbi-ditic and debris-flow samples from Hole 530B and inthe bioturbated oozes from Hole 532, agreeing with thelithologic similarities described by Hay et al. (1982).

This chapter gives further comparisons of the organ-ic matter content of sediments from Holes 53OB and532. Distributions of extractable and bound n-alkanes,w-alkanoic acids, and π-alkanols are examined as indica-tors of sources and preservation of organic matter.

METHODS

Biogenic sediments were obtained by continuous hydraulic pistoncoring, a procedure which minimizes sediment disturbance, at DSDPSites 530 and 532 (Fig. 1). Samples were selected shortly after core sec-

1089

P. A. MEYERS, K. W. DUNHAM

10° N

0° r

10° S

10 W 0c 10° E 20° 30°

Figure 1. Locations of Site 530 in the Angola Basin and Site 532 on the Walvis Ridge which were sampledby hydraulic piston coring during DSDP Leg 75. Site 532 is about 1 km downslope from Site 362,which was sampled by rotary drilling during DSDP Leg 40. (Bathymetric contours given in m.)

tions were opened on board D/V Glomar Challenger and frozen im-mediately in Kapak bags for storage. The samples were subsequentlyfreeze-dried in preparation for shore-based analysis.

Two Pleistocene samples from Hole 530B in the Angola Basin (wa-ter depth 4639 m) and one Pleistocene sample from Hole 532 on theWalvis Ridge (water depth 1341 m) were chosen for comparison. Inaddition, a late Miocene sample (Sample 532-58-2, 80-90 cm) was se-lected for contrast. General descriptions of these samples and their or-ganic matter contents are given in Table 1.

A two-stage extraction procedure was used to obtain the geolipidcontents of the freeze-dried samples. Soxhlet extraction with toluene/methanol yielded the easily extracted, unbound fraction of geolipids.A second extraction with 0.5 N KOH in methanol/toluene providedthe hydrolyzable and bound components. Both fractions were treatedwith methanolic boron trifluroide to convert fatty acids to their meth-yl esters, and then geolipid subfractions were separated by columnchromatography on alumina over silica gel. The subfractions so ob-tained were alkanes, fatty acid methyl esters, and hydroxy lipids. Thehydroxy subfraction was silylated with BSTFA prior to gas chromatog-raphy.

Splitless injection gas-liquid chromatography was employed tocharacterize the geolipid subfractions. A Hewlett-Packard 5880 FIDgas chromatograph equipped with a 20 m SE54 fused silica capillarycolumn was used with hydrogen as carrier gas. Individual compoundswere tentatively identified by retention times in this preliminary quali-tative survey. Data have been corrected for laboratory contaminantsand for mass discrimination over the wide molecular-weight rangessurveyed.

RESULTS AND DISCUSSION

General

The Pleistocene samples listed in Table 1 are rich indiatom remains and have concentrations of organic car-bon substantially higher than the mean of 0.2% givenfor modern deep-ocean sediments by Degens and Mop-per (1976). Abundant concentrations of biogenic opaland organic carbon are two of the important indicators

Table 1. General descriptions and organic contents of hydraulic piston core samples, from DSDP Leg 75.a

Sample(interval in cm)

Angola Basin

530B-4-1, 75-80

530B-9-2, 110-120

Walvis Ridge

532-5-2, 100-110

532-58-2, 80-90

Waterdepth (m)

4629

4629

1331

1331

Sub-bottomdepth (m)

12

35

20

237

Age

Pleistocene

Pleistocene

Pleistocene

late Miocene

Sedimentdescription (

Debris flow diatom-nannofossil ooze

Debris flow diatom-nannofossil ooze

Bioturbated dark-olivediatom clay

Bioturbated dark-olivenannofossil clay

6

15

4

44

) C o r g (%)

2.7

1.8

9.7

2.1

Atomic C/N

15.6

7.8

26.3

16.1

From Meyers, Brassell, and Hue (this volume).

1090

GEOLIPID COMPARISON OF BIOGENIC SEDIMENTS

of high productivity resulting from upwelling that arelisted by Diester-Haass (1978). The late Miocene sam-ple, although also rich in organic carbon, contains lessopal and may represent an earlier stage in the develop-ment of the upwelling flora in this part of the easternSouth Atlantic Ocean. All four of these Leg 75 samplescontain more opal and have much greater amounts oforganic carbon than do Pleistocene-through-Miocenesamples from DSDP Sites 525 and 528 on the WalvisRidge (Meyers and Keswani, in press). These Leg 74sites are about 1000 km seaward of the Leg 75 locations,and their sediments accumulated under open-ocean ar-eas having low surface productivity but in water depths1 to 2 km shallower than at Site 530 in the Angola Ba-sin. Suess (1980) has noted that the flux of organic mat-ter to the deep sea continually decreases with increasingdepth, and so the relatively high values of organic car-bon in the Angola Basin samples are exceptional.

Atomic C/N ratios of the four samples in Table 1 arewithin the range reported for young marine sediments(Muller, 1977) but are higher than values found in or-ganic-carbon-lean samples of similar ages from DSDPLegs 58 (Waples and Sloan, 1980), 72 (Meyers andDunham, in press), and 74 (Meyers and Keswani, inpress). The ratios in Table 1 are typical of marine-de-rived organic matter (Muller, 1977). Although the deepersample of each pair of samples from both locations hasa lower C/N ratio than its shallower counterpart, thefull set of C/N data given by Meyers, Brassell, and Hue(this volume) shows no depth-related change in these ra-tios in sediments younger than middle Miocene. The ef-fects of diagenesis in lowering C/N ratios, documentedby Waples and Sloan (1980) in organic-carbon-lean sedi-ments from DSDP Leg 58, evidently is concealed in sed-iments richer in organic matter.

Alkalies

Distributions of both free and bound n-alkanes inPleistocene samples from the Angola Basin (Hole 530B)and in Pleistocene and Miocene samples from theWalvis Ridge (Hole 532) are dominated by odd-carbon,long-chain components (Fig. 2). Land plants commonlyhave hydrocarbon compositions dominated by C27,C29, and C31 «-alkanes, whereas algae contain mostlyshorter-chain components in the C16 to C20 range (Si-moneit, 1978a). Quaternary sediments containing ter-rigenous hydrocarbon distributions like those at theselocations have been reported at other DSDP sites. Someexamples include Sites 436 and 440 in the Japan Trench(Brassell et al., 1980; Rullkötter et al., 1980a), Sites 467,469, and 471 offshore at southern California (Rullköt-ter et al., 1981; McEvoy et al., 1981; Simoneit and Ma-zurek, 1981), and Sites 487 and 491 in the Middle Amer-ica Trench (Brassell et al., 1981). The dominant «-al-kane in these examples is Λ-C29, but it is «-C31 inQuaternary samples from Site 362 on the Walvis Ridge(Boon et al., 1978), Sites 442, 443, and 444 from north-ern Philippine Sea (Rullkötter et al., 1980b), and Sites515 and 517 in the western South Atlantic (Meyers andDunham, in press).

Downslope transport of organic matter derived fromthe African continent north of the Walvis Ridge maycontribute to the hydrocarbon distributions found in theAngola Basin, but it is unlikely that the Namibia coastalareas provide much land-plant matter because of theirdesert conditions. Hence, downslope transport is notlikely to be important in bringing land-derived materialto the Walvis Ridge sediments at Site 532. A more likelytransport process of terrigenous hydrocarbons to thislocation is by eolian dusts. Simoneit (1977) reports thatterrigenous components dominate the lipid character ofdust particles collected over the Atlantic Ocean. Be-cause /7-C31 dominates n-alkane distributions at Sites530 and 532, eolian input may be important to the hy-drocarbon contents of sediments deposited at both theseSouth Atlantic locations.

Chromatograms of the free hydrocarbon fractions ofall four samples contain an unresolved complex mixture(UCM) peaking around W-C20 while those of the boundfractions exhibit no UCM. None of the UCMs consti-tute more than half of the hydrocarbon fraction, andnone of the hydrocarbon chromatograms resemble thoseof potential shipboard contaminants (cf. Doran andJohnson, 1979). It is probable the UCMs arise from mi-crobial or possibly diagenetic processes rather than fromcontamination.

Pristane/phytane ratios in Table 2 are one or greaterin the free hydrocarbon subfractions of three of the foursamples. Such values indicate organic matter accumula-tion under aerobic bottom waters (Didyk et al., 1978).The values of less than one in the free hydrocarbons ofSamples 530B-4-1, 75-80 cm, and in all of the boundhydrocarbons, suggest deposition under anoxic condi-tions, and such conditions may occur as an intensifiedmidwater oxygen minimum zone in this part of theSouth Atlantic. Microbial contributions of hydrocar-bons are indicated by low pristane//i-C17 values in all ofthe Angola Basin subfractions and in the bound hydro-carbons in the Walvis Ridge samples. Because low pris-tane/«-C17 and pristane/phytane ratios are found to-gether, microbial activity may be responsible for bothratios, as well as for the UCMs seen in the free hydro-carbon subfractions.

Alkanoic Acids

Distributions of H-alkanoic acids from PleistoceneSections 530B-4-1, 530B-9-2, and 532-5-2 are comparedin Figure 3. All have strong even-to-odd carbon numberpredominances (Table 2) typical of biogenic acids. Thefree n-acids have bimodal distributions with maxima at«-C16 and n-C26, whereas the bound acid fractions aredominated by n-Clβ and have only small contributionsof longer chain-length acids. Similar differences be-tween distributions of free and bound n-alkanoic acidshave been described in samples of Pleistocene diatoma-ceous clays from DSDP Site 440 in the Japan Trench(Brassell et al., 1980).

Because the free acid subfraction constitutes the ma-jor fraction of the total acids in DSDP samples (Brassellet al., 1980; Meyers, Trull, and Kawka, this volume) and

1091

P. A. MEYERS, K. W. DUNHAM

100Free

50-

Sample530B-4-1,75-80 cm

4-U•

100Bound

5 0 -

Sample 530B-4-1,75-80 cm

o ' i r17 19 21 23 25 27 29 31 33 17 19 21 23 25 27 29 31 33

100-

5 0 -

it p

erce

i

o

Sample 530B-9-2,100-120 cm

• IMM I I I I I - I -

50-

Sample 530B-9-2,100-120 cm

17 19 21 23 25 27 29 31 33

g 100

1 •α>

50-

0

100

Sample 532-5-2,100-110 cm

_LiL

5 0 -

0 -

17 19 21 23 25 2/ 29 31

Sample 532-5-2,100-110 cm

II M-l

33

17 19 21 23 25 27 29 31 33 17 19 21 23 25 27 29 31 33

50-

Sample 532-58-2,80-90 cm

-Φ-

100-

5 0 -

Sample 532-58-2,80-90 cm

17 19 21 23 25 27 29 31 33 17 19 21

n Alkane chain length

23 25 27 29 31 33

Figure 2. Histograms of free (left) and bound (right) n-alkanes normalized to the major component ineach distribution (100%). Sample 532-58-2, 80-90 cm is late Miocene; the others are Pleistocene. Pris-tane and phytane represented by dotted and dashed lines, respectively.

because the extraction procedure used to obtain freeacid subfractions and the procedures employed by otherinvestigators to obtain total acids are similar, distribu-tions of free acids of these Leg 75 samples can be com-pared with total acid distributions from other DSDPsamples. In general, w-alkanoic acid distributions presentin Quaternary sediments from ocean margin areas aresimilar to the free acid distributions shown in Figure 3.Examples of similar distributions are found in Pleisto-cene and Pliocene sediments from Site 362 on theWalvis Ridge (Boon et al., 1978), a Pleistocene samplefrom Site 364 in the Angola Basin (Simoneit, 1978),Quaternary diatomaceous clays from the CaliforniaBorderland (Simoneit and Mazurek, 1981), and Quater-nary sediments from the Middle America Trench (Bras-sell et al., 1981). In these distributions, the prominenceof C24, C26, and C28 H-acids indicates important con-tributions of land-plant acids (cf. Simoneit, 1978a). The

widespread occurrence of W-C16 and n-C18 acids in ter-rigenous plants, marine algae, and bacteria makes themuseful as evidence of biological origin but not as specificsource indicators. The relative abundances of W-C14 inthe free and bound distributions in Figure 3 suggest al-gal or bacterial inputs (Simoneit, 1978; Brassell et al.,1981). In addition, wax esters believed to originate fromdiatoms have been described in modern Namibian shelfsediments (Boon and deLeeuw, 1979) and may contrib-ute to the important amounts of C14, C16, and C18 n-alkanoic acids in the Leg 75 samples.

In contrast to the distributions of fatty acids found inthe Quaternary sediments from near the African andother continental margins, few long-chain, terrigenousw-acids are present in organic-carbon-lean sedimentsfrom the Brazil Basin and Rio Grande Rise (Meyers andDunham, in press) or from Leg 74 sites on the WalvisRidge (Meyers and Keswani, in press). Their absence

1092

GEOLIPID COMPARISON OF BIOGENIC SEDIMENTS

Table 2. Ratios of geolipid components extracted from hydraulic pis-ton core samples from DSDP Leg 75.

Geolipidfraction

Alkanes

Pristane/phytanePristane/n-C17n-C29/n-C17Odd/even1

Alkanoic acids

n-C26/n-C16Even/odd

Alcohols

π-C26/n-C16Even/odd3

C29/C27 stenols

530B-4-175-80

Free

0.60.71.52.0

0.94.2

1.92.50.8

Bound

0.40.33.51.4

0.24.1

1.11.30.6

Sample(interval in cm)

530B-9-2110-120

Free

1.00.69.64.1

2.45.1

4.83.71.6

Bound

0.60.35.82.6

0.34.6

1.31.71.0

532-5-2100-110

Free

2.01.15.71.9

0.75.8

1.92.11.9

Bound

0.70.42.12.6

0.16.5

1.11.01.2

532-58-280-90

Free Bound

1.4 0.61.2 0.6

10.0 7.51.7 1.2

— —

-

Note: Dashes-not analyzed.1 Over range of C17 to C32.2 Over range of C14 to C31.3 Over range of C15 to C28 π-alkanols.

probably reflects their destruction during early diagene-sis, because terrigenous n-alkanes are important constit-uents of the sediment lipids at many DSDP sites andshow that land-plant components are transported todeep-ocean sediments.

Alkanols and Stenols

Distributions of n-alkanols from Pleistocene samplesfrom Holes 53OB and 532 are shown in Figure 4. Thefree «-alkanols are dominated by n-C22, «-C26 andhave obvious even-carbon-number predominances (Ta-ble 2). Bound alcohol fractions in general have weakereven-carbon-number predominances and contain rela-tively smaller contributions of long-chain alkanols.

Alkanols extracted from Quaternary sediments fromother DSDP sites either under or near to areas of highmarine productivity, and hence containing relativelyhigh amounts of organic carbon, have distributions sim-lar to those found at these two Leg 75 sites. Some ofthese other locations include Site 362 (Boon et al.,1978), Site 440 (Brassell et al., 1980), and Sites 487 and491 (Brassell et al., 1981). The presence of the long-chain n-alkanols in DSDP sediments has been inter-preted as indicating terrigenous inputs (Brassell et al.,1981) and is consistent with the important contributionsof terrigenous n-alkanes arid /z-alkanoic acids in thesamples from Holes 53OB and 532 (Figs. 2 and 3). Suchrelatively large amounts of land-derived lipids in sedi-ments found under areas of high production of marineorganic matter may result from enhanced preservationof all types of organic materials. Further evidence ofgood preservation is indicated by the presence of unsat-

100-Bound

5 0 -

Sample 530B-4-1,7 5 - 8 0 cm

14 16 18 20 22 24 26 28 30 32100

•| 5 0 -

0

100

Sample 530B-9-2,

100-120 cm

14 16 18 20 22 24 26 28 30 32

5 0 -

Sample 532-5-2,

100-110 cm

• H - I I I I i I i i

100Free

5 0 -

Sample530B-4-1,7 5 - 8 0 cm

14 16 18 20 22 24 26 28 30 32

100

5 0 -

Sample530B-9-2,

100-120 cm

14 16 18 20 22 24 26 28 30 32100-

5 0 -

Sample 532-5-2,

100-110 cm

14 16 18 20 22 24 26 28 30 32 14 16 18 20 22 24 26 28 30 32

n Alkanoic acid chain length

Figure 3. Histograms of free (right) and bound (left) «-alkanoic acids of Pleistocene diatomaceous clays.Distributions are normalized to their major component (100%).

1093

P. A. MEYERS, K. W. DUNHAM

100Free

5 0 -

Sample 530B-4-1,75-80 cm

100Bound

50 -

14 16 18 20 22 24 26 28 30

Sample 530B-4-1,75-80 cm

14 16 18 20 22 24 26 28 30

100

~ 5 0 -

0

100

Sample 530B-9-2,100-120 cm

100

50-

Sample 530B-9-2,100-120 cm

14 16 18 20 22 24 26 28 30 14 16 18 20 22 24 26 28 30

50-i

Sample 532-5-2,100-110 cm

100

50-

Sample 532-5-2,100-110 cm

14 16 18 20 22 24 26 28 30 14 16 18 20 22 24 26 28 30n- Alkanol chain length

Figure 4. Histograms of free (left) and bound (right) n-alkanols of Pleistocene diatomaceous clays. Distri-butions are normalized to their major component (100%).

urated alcohols, stenols, in the Pleistocene samples. Ra-tios of land-derived C29 stenols to marine-derived C27stenols (Huang and Meinschein, 1976) agree with othersource indicators in showing important terrigenous in-puts (Table 2).

Comparison of Samples

Pleistocene sediments from Hole 53OB in the AngolaBasin contain similar amounts of organic matter andhave similar distributions of lipid source indicators ascompared to the Pleistocene sample from Hole 532 onthe Walvis Ridge. These organic matter characteristicsappear to be common to Quaternary sediments foundunder ocean margin areas having high surface produc-tivity and hence are not positive proof of a common ori-gin for the Quarternary sediments at these Leg 75 loca-tions. The similarities in organic character, however, agreewith other similarities in fossil content and sedimentolo-gy. This overall agreement strongly suggests that sedi-ments from Hole 53OB and from Hole 532 originatedfrom similar depositional environments and that theAngola Basin sediments have undergone downslope re-location from areas on the Walvis Ridge. Such reloca-tion is indicated by evidence of debris flows in the hy-draulic-piston-cored Hole 53OB sediments and by therelatively high concentrations of organic carbon in these

sediments, suggesting that deposition was originally atshallower depths (cf. Suess, 1980).

CONCLUSIONS1. Samples of Pleistocene and late Miocene sediment

from Hole 53OB in the Angola Basin and Hole 532 onthe Walvis Ridge have geolipid distributions of mixedmarine and terrigenous character. In general, land-plantcomponents provide larger contributions to distributionsof w-alkanes, /z-alkanoic acids, and «-alkanols than doalgal or bacterial components.

2. Geolipid distributions give evidence of relativelygood preservation of organic matter.

3. Eolian input of continental materials to these oce-anic sediments is inferred from important amounts ofland-plant components in the geolipid distributions.

4. Strong similarities in the organic character of thesediments from these two locations suggest a commondepositional environment, probably on the Walvis Ridge.Sediments at Site 530 in the Angola Basin have under-gone relocation to their present position from their ini-tial sites of deposition at shallower depths.

ACKNOWLEDGMENTS

We thank M. J. Leenheer, J. G. Quinn, and E. S. Van Vleet for re-viewing this chapter and for suggesting ways to improve it. We are

1094

GEOLIPID COMPARISON OF BIOGENIC SEDIMENTS

grateful to the Deep Sea Drilling Project/International Phase ofOcean Drilling for providing the opportunity for P. A. M. to partici-pate in Leg 75.

REFERENCES

Boon, J. J., and deLeeuw, J. W., 1979. The analysis of wax esters, verylong mid-chain ketones, and sterol ethers isolated from Walvis Baydiatomaceous ooze. Mar. Chern., 7:117-132.

Boon, J. J., van der Meer, F. W., Schuyl, P. J. W., de Leeuw, J. W.,Schenck, P. A., and Burlingame, A. L., 1978. Organic geochemi-cal analyses of core samples from Site 362,Walvis Ridge, DSDPLeg 40. In Bolli, H. M., Ryan, W. B. F., et al., Init. Repts. DSDP,Suppl. to Vols. 38, 39, 40, and 41: Washington (U. S. Govt. Print-ing Office), 627-637.

Brassell, S. C , Comet, P. A., Eglinton, G., Isaacson, P. J., McEvoy,J., Maxwell, J. R., Thomson, I. D., Tibbets, P. J. C , andVolkman, J. K., 1980. Preliminary lipid analyses of Sections 440A-7-6, 440B-3-5, 440B-8-4, 440B-68-2, and 436-11-4: Legs 56 and 57,Deep Sea Drilling Project. In Scientific Party, Init. Repts. DSDP,56, 57, Pt 2: Washington (U. S. Govt. Printing Office), 1367-1390.

Brassell, S. C , Eglinton, G., and Maxwell, J. R., 1982. Preliminarylipid analyses of two Quaternary sediments from the MiddleAmerica Trench, southern Mexico transect, Deep Sea DrillingProject Leg 66. In Watkins, J. S., Moore, J. C. et al., Init. Repts.DSDP, 66: Washington (U. S. Govt. Printing Office), 557-580.

Degens, E. T., and Mopper, K., 1976. Factors controlling the distribu-tion and early diagenesis of organic material in marine sediments.In Riley, J. P., and Chester, R. (Eds.), Chemical Oceanography(Vol. 6): New York (Academic Press), 59-113.

Didyk, B. M., Simoneit, B. R. T., Brassell, S. C , and Eglinton, G.,1978. Organic geochemical indicators of paleoenvironmental con-ditions of sedimentation. Nature, 272:216-222.

Diester-Haas, L., 1978. Sediments as indicators of upwelling. In Boje, R.,and Tomczak, M. (Eds.), Upwelling Ecosystems: Berlin (Springer-Verlag), pp. 261-281.

Diester-Haass, L., and Schrader, H. J., 1979. Neogene coastal upwell-ing history off northwest and southwest Africa. Mar. Geol.,29:39-53.

Doran, T., and Johnson, P. G., 1979. Examination of potential geo-chemical contaminants in Leg 48 material. In Montadert, L., Ro-berts D. G., et al., Init. Repts. DSDP, 48: Washington (U. S. Govt.Printing Office), 1157-1160.

Erdman, J. G., and Schorno, K. S., 1978. Geochemistry of carbon:Deep Sea Drilling Project Leg 40. In Bolli, H. M., Ryan, W. B. F.et al., Init. Repts. DSDP, Suppl. to Vols. 38, 39, 40, and 41: Wash-ington (U. S. Govt. Printing Office), 651-658.

Hay, W. W., Sibuet, J. C , and Shipboard Scientific Party, 1982. Sedi-mentation and accumulation of organic carbon in the Angola Ba-sin and on the Walvis Ridge: Preliminary results of Deep Sea Drill-ing Project Leg 75. Geol. Soc. Am. Bull., 93:1038-1050.

Huang, W. Y., and Meinschein, W. G., 1976. Sterols as source indica-tors of organic materials in sediments. Geochim. Cosmochim. Ac-ta, 40:323-330.

McEvoy, J., Eglinton, G., and Maxwell, J. R., 1981. Preliminary lipidanalyses of sediments from Sections 467-3-3 and 467-97-2. InYeats, R. S., Haq, B. IL, et al., Init. Repts. DSDP, 63: Washing-ton (U. S. Govt. Printing Office), 763-774.

Meyers, P. A., and Dunham, K. W., in press. Organic geochemistry ofQuaternary sediments from Deep Sea Drilling Project Leg 72,South Atlantic Ocean. In Barker, P. F., Carlson, R. L., Johnson,D. A., et al., Init. Repts. DSDP, 72: Washington (U. S. Govt.Printing Office).

Meyers, P. A., and Keswani, S. R., in press. Organic geochemistry ofNeogene Walvis Ridge sediments from Deep Sea Drilling ProjectLeg 74. In Moore, T. C , Jr., Rabinowitz, P. D., et al., Init. Repts.DSDP, 74: Washington (U. S. Govt. Printing Office).

Muller, P. J., 1977, C/N ratios in Pacific deep-sea sediments: Effect ofinorganic ammonium and organic nitrogen compounds sorbed byclays. Geochim, Cosmochim. Acta, 41:765-776.

Rullkötter, J., Cornford, C , Flekken, P., and Welte, D. H., 1980a.Organic geochemistry of sediments cored during Deep Sea DrillingProject Legs 56 and 57, Japan Trench: Organic petrography andextractable hydrocarbons. In Scientific Party, Init. Repts. DSDP,56, 57, Pt. 2: Washington (U. S. Govt. Printing Office), 1291-1304.

Rullkötter, J., Flekken, P., and Welte, D. H., 1980b. Organic petrog-raphy and extractable hydrocarbons of sediments from the north-ern Phillippine Sea. Deep Sea Drilling Project Leg 58. In Klein, G.deV, Kobayashi, K., et al., Init. Repts. DSDP, 58: Washington(U.S. Govt. Printing Office), 755-762.

Rullkötter, J., von der Dick, H., Welte, D. H., 1981. Organic petrog-raphy and extractable hydrocarbons of sediments from the easternNorth Pacific Ocean, Deep Sea Drilling Project Leg 63. In Yeats,R. S., Haq, B. E. et al., Int. Repts. DSDP, 63: Washington (U. S.Govt. Printing Office), 819-836.

Siesser, W. G., 1980. Late Miocene origin of the Benguela upwellingsystem off northern Namibia. Science, 208:283-285.

Simoneit, B. R. T., 1977. Organic matter in eolian dusts over the At-lantic Ocean. Mar. Chern., 5:443-464.

, 1978a. The organic geochemistry of marine sediments. InRiley, J. P., and Chester, R. (Eds.), Chemical Oceanography (Vol.7): London (Academic Press), 233-311.

., 1978b. Lipid analyses of sediments from Site 364 in theAngola Basin, DSDP Leg 40. In Bolli, H. M., Ryan, W. B. F., etal., Init. Repts. DSDP, Suppl. to Vols. 38, 39, 40, and 41: Wash-ington (U. S. Govt. Printing Office), 659-662.

Simoneit, B. R. T., and Mazurek, M. A., 1981. Organic geochemistryof sediments from the southern California Borderland, Deep SeaDrilling Project Leg 63. In Yeats, R. S., Haq, B. U., et al., Init.Repts. DSDP, 63: Washington (U. S. Govt. Printing Office), 837-853.

Suess, E., 1980. Particulate organic carbon flux in the oceans—sur-face productivity and oxygen utilization. Nature, 288:260-263.

Waples, D. W, and Sloan, J. R., 1980. Carbon and nitrogen dia-genesis in deep sea sediments. Geochim. Cosmochim. Acta, 44:1463-1470.

Date of Initial Receipt: January 18, 1983

1095