cruise report 2006 - spitsbergen report 2006 - spitsbergen.pdf · cruise report – west...

CRUISE REPORT

MARINE-GEOLOGICAL CRUISE TO WEST SPITSBERGEN FJORDS

on R/V Jan Mayen, August 3rd – August 6th 2006

by

Matthias Forwick

DEPARTMENT OF GEOLOGY, UNIVERSITY OF TROMSØ, N-9037 TROMSØ, NORWAY

R/V ”Jan Mayen” at Kullkaia in Longyearbyen on August 6th 2006; Foto: M. Forwick

Cruise report – West Spitsbergen fjords, August 2006

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MARINE-GEOLOGICAL CRUISE TO WEST SPITSBERGEN FJORDS Content Page

1. Summary 3

2. Background 4

3. Objectives 4

4. Participants 5

5. Equipment 6

6. Methods 7

7. Journal 8

8. Preliminary results 14

9. References 15

10. Tables of collected data 16

Remarks: Jan P. Holm and Steinar Iversen from the Department of Geology, University of Tromsø, contributed with data processing and the creation of figures to this cruise report. They are hereby acknowledged! The report was finalised on April 5th 2007.


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1. Summary From the evening of August 3rd to the afternoon of August 6th 2006, the Department of Geology of the University of Tromsø (UiTø), Norway, arranged a scientific cruise to West Spitsbergen fjords on R/V “Jan Mayen” of the University of Tromsø. Investigated areas were Isfjorden, Tempelfjorden, Sassenfjorden, Billefjorden, Ymerbukta and Trygghamna (Fig. 1). In Sassenfjorden and Tempelfjorden, 8 conductivity-temperature-depth and turbidity measurements (CTDT) were performed and one gravity core was retrieved. Two CTDT casts were performed in Billefjorden. In central and inner parts of Isfjorden, one CTDT cast was carried out. Furthermore, two gravity cores and three piston cores were retrieved in this area. One CTDT cast in each Ymerbukta and Trygghamna have been performed. Whereas one piston core has been retrieved from Ymerbukta, one box core has been sampled in Trygghamna. Swath bathymetry data have been systematically collected in the inner parts of Isfjorden and in Billefjorden.

Figure 1: Location map (A) and map showing locations mentioned in the report (B).


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2. Background The cruise was arranged as part of the strategic university programme “Sedimentary Processes and Paleoenvironment on Northern Continental Margins” (SPONCOM). The overall goal of the project was to assess the changes in the physical environment of the sea-floor and the overlying water and ice of West Spitsbergen and North Norwegian fjords, as well as on adjacent continental margins during the last glacial – interglacial cycle. 3. Objectives The objectives of the cruise were: - To expand the existing swath-bathymetry data sets in Isfjorden and Billefjorden. - The retrieval of eight box cores for surface sampling (0-1 cm), as well as CTD measurements

in Sassenfjorden and Tempelfjorden in order to continue monitoring of the influence of environmental changes on foraminifera-fauna assemblages in these fjords (see Korsun & Hald, 2000).

- To continue measurements of physical properties of and sediment concentrations in the water masses in Sassenfjorden and Tempelfjorden, in order to obtain information about the influence of the river Sassenelva, as well as the glaciers Tunabreen and Von Postbreen on the water columns in these fjords.

- To retrieve surface samples from Sassenfjorden and Tempelfjorden for micro-biological, geochemical and mineralogical analyses, in order to investigate lateral impact of the river Sassenelva, as well as the glaciers Tunabreen and Von Postbreen on the sedimentation pattern in these fjords.

- To retrieve gravity cores and piston cores from the inner parts of Isfjorden, in order to obtain a better chronological control on the deglaciation of the area at the end of the last glacial period.

- To retrieve a box core from Trygghamna and a piston core from Ymerbukta with the purpose of analysing the geochemical/mineralogical and granulometric compositions of the sediments, as well as to investigate sedimentary processes in Ymerbukta.


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4. Participants

Crew R/V “Jan Mayen”: Captain: John K. Almestad Vice captain: Inge Berg Chief engineer: Arne M. Viik First engineer: Tom E. Gulseth Boatswain: Oddmun P. Kopperstad Boatswain: Bjørn I. Mann Able seaman: Rune Kismul Able seaman: Geir Sørensen Able seaman: Geir B. Nygård Stewart: Ulf R. Holm Galley assistant: Steven Andresen Scientific crew: Participant Affiliation Matthias Forwick, Post. Doc., chief scientist UiTø, Dept. Geol. Steinar Iversen, engineer UiTø, Dept. Geol. Kyrre Lydersen, engineer UiTø, NCFS Jan. P. Holm, engineer UiTø, Dept. Geol. Trine Dahl, engineer UiTø, Dept. Geol. Nicole J. Baeten, M.Sc. student UiTø, Dept. Geol. Dr. Jae-Il Lee KOPRI Dr. Kyu-Cheul Yoo KOPRI Dr. Yul Roh CNU Prof. Ross D. Powell NIU Prof. Julie Brigham-Grette UofM Dr. Tove Nielsen UNIS Stig Arne Holtedahl UiTø, Dept. Geol. Annbjørg Johansen UiTø, Dept. Geol. UiTø, Dept. Geol. = University of Tromsø, Department of Geology, Tromsø, Norway UiTø, NCFS = University of Tromsø, Norwegian College of Fishery Science, Tromsø, Norway KOPRI = Korea Polar Research Institute, Incheon, South Korea CNU = Chonnam National University, Gwangju, South Korea NIU = Northern Illinois University, De Kalb, Illinois, U.S.A. UofM = University of Massachusetts Amherst, Massachusetts, U.S.A. UNIS = The University Centre in Svalbard


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5. Equipment Acoustic equipment Kongsberg Maritime EM 300 multibeam echo sounder 3.5 kHz penetration echo sounder: Geoacoustic/Ferranti O.R.E., 10 kW hull-mounted penetration echo sounder, 2 pulses, 3-5 kHz bandpass-filter settings Transmitter: Geopulse 5430A Receiver: Geopulse 5210A EPC 9800 thermo recorder, 2 channel Digital recorder: PC with Delph 2 channel; log format: ELICS; Store formats: DVD Echo Sounder, Simrad EK 500, 38 kHz Coring equipment Piston corer (total weight c. 2200 kg; 2*6 m steel barrels; inner diameter of steel barrel: 11 cm) Gravity corer (total weight 1900 kg; 6 m steel barrel; inner diameter of steel barrel: 11 cm) Giant box corer (50*50*50 cm3) Water properties: CTD (Seabird 911 Plus) with compact rosette SEATECH transmissiometer (660 nm wavelength, 25 cm beam pathlength) – attached to CTD


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6. Methods Acoustic investigations Seafloor mapping: Swath-bathymetry surveys have been carried out using a Kongsberg Maritime EM 300 multibeam echo sounder. A sound velocity profile of the water column for calibrating the equipment was recorded from CTD casts within the mapped areas. The ship’s speed during data acquisition was generally between 8 and 10 kn. The equipment worked well during the data acquisition and the results are of good quality. The collected data are stored on DVD. Subsequent data cleaning was performed using the software programme Neptune version 4.1.2. Gridding and visualising of the results has been carried out in GMT (The Generic Mapping Tools). High-resolution profiling: Seismic profiles using a hull mounted 3.5 kHz penetration echo sounder data were collected along several ship tracks during the swath-bathymetry data acquisition in Billefjorden and inner Isfjorden. The equipment worked satisfactory and the data appear to be of good quality. The available data are stored on DVD. Sediment sampling The seafloors in Sassenfjorden, Tempelfjorden, Ymerbukta, Trygghamna, as well as in central and inner Isfjorden have been sampled with a piston corer (PC), a gravity corer (GC) and a giant box corer (BC).

Long cores were retrieved with a 12-m long piston corer and a 6-m long gravity corer, respectively. Plastic liners with an outer diameter of 11 cm (inner diameter: 10 cm) were put into the steel barrels. After retrieval, the plastic liners were cut into sections of up to 100 cm length. They were covered with plastic caps, taped and stored at +4ºC. At station JM06-176-GC, material for biogeochemical analyses was sampled from the tops of the 1-m sections. The remaining material was subsequently removed.

The giant box corer has been used with the purpose of retrieving undisturbed samples of the seafloor. After taking colour pictures, the uppermost one centimetre from the box cores in Sassenfjorden and Tempelfjorden was sampled with a spoon and put into plastic and glass bottles. The uppermost one centimetre from the material retrieved at the other box-core stations was put into glass bottles. The plastic bottles were stored at +4°C whereas the material in the glass bottles was prepared for biogeochemical analyses. Water properties Water properties – temperature, salinity – were measured using a CTD (Seabird 911 Plus). Additionally, the suspension contents in the water masses were measured using a SEATECH transmissiometer. Data collection was performed during downcasts at a speed of 0.5 m/s. Water samples were taken at several stations. The water will be filtered in the laboratory in order to estimate the sediment concentration and in order to perform geochemical analyses with the purpose of identifying the nature of the suspended load.


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7. Journal Thursday, August 3rd 2006 Weather: overcast; calm sea; 6-7 ºC; wind: <5 m/sec. Summary Departure from Longyearbyen at 18:00 UTC (20:00 local time), heading for Billefjorden, in order to collect swath bathymetry data in the inner parts of the fjord, off Pyramiden. Protocol of August 3rd (times in UTC) 1800: Departure from Longyearbyen 2036: Station JM06-169-CTDT (conductivity-temperature-depth-transmissivity) in Billefjorden

(Fig. 2; Tab. 1) 2306: Start of swath-bathymetry data collection in inner Billefjorden, off Pyramiden (station

number 170) Friday, August 4th 2006 Weather: overcast; calm sea; ~6-7 °C; wind: <6 m/sec. Summary Continuing collection of swath bathymetry data in inner Billefjorden; one piston core (PC) station in inner Isfjorden; four gravity-core (GC) stations in inner Isfjorden and Sassenfjorden, respectively; eight CTDT and box-corer (BC) stations in Sassenfjorden and Tempelfjorden; one CTDT station in outer Billefjorden; collection of swath bathymetry data in outer Billefjorden/inner Isfjorden. Protocol of August 4th (times in UTC) ~0500: End of swath-bathymetry data collection in inner Billefjorden (station number 170)–

steaming to inner Isfjorden 0606: Station JM06-171-GC in inner Isfjorden (Fig. 3; Tab. 2) 0644: Station JM06-172-GC in inner Isfjorden 0718: Station JM06-173-GC in inner Isfjorden 0820: Station JM06-174-PC in inner Isfjorden (Fig. 4; Tab. 3) 0947: Station JM06-175-CTDT in Sassenfjorden (Fig. 2; Tab. 1) 1216: Station JM06-176-GC in Sassenfjorden 1256: Station JM06-177-CTDT in Sassenfjorden 1331: Station JM06-178-BC in Sassenfjorden (Fig. 5; Tab. 4) 1348: Station JM06-179-CTDT in Sassenfjorden/Tempelfjorden ~1500: Station JM06-180-BC in Sassenfjorden/Tempelfjorden 1546: Station JM06-181-CTDT in Tempelfjorden 1556: Station JM06-182-BC in Tempelfjorden 1624: Station JM06-183-CTDT in Tempelfjorden 1640: Station JM06-184-BC in Tempelfjorden 1707: Station JM06-185-CTDT in Tempelfjorden 1734: Station JM06-186-BC in Tempelfjorden 1842: Station JM06-187-CTDT in Tempelfjorden


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1901: Station JM06-188-BC in Tempelfjorden 1946: Station JM06-189-CTDT in Tempelfjorden 1953: Station JM06-190-BC in Tempelfjorden 2110: Station JM06-191-BC in Sassenfjorden 2232: Station JM06-192-CTDT in outer Billefjorden 2244: Start of swath-bathymetry data collection in outer Billefjorden/inner Isfjorden (station

number 193) Saturday, August 5th 2006 Weather: overcast, partly foggy; calm sea; ~6-9 °C; wind: <6 m/sec. Summary Continuing collection of swath bathymetry data in outer Billefjorden/inner Isfjorden; three PC stations in inner, central Isfjorden and Ymerbukta, respectively; one GC in central Isfjorden; one BC station in Trygghamna; three CTDT stations in inner Isfjorden, Ymerbukta and Trygghamna, respectively; continuing collection of swath-bathymetry data in inner Isfjorden/outer Billefjorden Protocol of August 5th (times in UTC) ~0600: End of swath-bathymetry data collection in outer Billefjorden/inner Isfjorden (station

number 193) 0712: Station JM06-194-PC in inner Isfjorden (Fig. 4; Tab. 3) 0907: Station JM06-195-PC in central Isfjorden 1158: Station JM06-196-CTDT in Ymerbukta (Fig. 2; Tab. 1) 1210: Station JM06-197-PC in Ymerbukta 1450: Station JM06-198-CTDT in Trygghamna 1512: Station JM06-199-BC in Trygghamna (Fig. 5; Tab. 4) 1658: Station JM06-200-GC in central Isfjorden (Fig. 3; Tab. 2) 1823: Station JM06-201-CTDT in inner Isfjorden 1921: Start of swath-bathymetry data collection in inner Isfjorden/outer Billefjorden (station

number 202) Sunday, August 6th 2006 Weather: first overcast, later clear sky; calm sea; ~6-10 °C; wind: max. ~6 m/sec. Summary Finishing collection of swath bathymetry data in inner Isfjorden/outer Billefjorden; return to Longyearbyen. Protocol of August 6th (times in UTC) ~0900: End of swath-bathymetry data collection in inner Isfjorden/outer Billefjorden (station

number 202) ~1030: Arrival in Longyearbyen (”Kullkaia”)


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Figure 2: Conductivity-temperature-depth-transmissivity stations.


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Figure 3: Gravity-corer stations.


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Figure 4: Piston-corer stations.


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Figure 5: Box-corer stations.


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8. Preliminary results

Figure 6: Swath bathymetry data from Billefjorden and preliminary interpretations. The figure shows a compilation of data collected during previous cruises and during this cruise.


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Billefjorden comprises several sills / shallow areas and basins (Fig. 6). The most pronounced shallow area is located at the mouth of the fjord, off Skansebukta. A more than 200 m deep basin is located within this shallow area. Further infjord, one north-south oriented basin and one north-south oriented sill occur. Because these two features are located parallel to the Billefjorden Fault Zone (e.g. Dallmann et al., 2004) it is reasonable to assume that their formation was related to tectonic activity. The largest basin is located in the central and inner parts of Billefjorden. It has maximum water depths of >200 m. Several morphological features can be identified within this basin. Linear features that are oriented parallel to the fjord axis are suggested to be glacial lineations that have been formed at the base of fast-flowing ice streams during the last glacial period. Numerous ridges that are oriented perpendicular to the fjord axis overly the glacial lineations. It is assumed that these are recessional morainal banks (e.g. Ottesen & Dowdeswell, 2006) that have been deposited during a period of general glacier retreat at the end of the Last Glacial. After the deglaciation of the fjord, the side walls have been partly exposed to slope failure. Several circular depressions are distributed throughout the inner basin. These features are suggested to be pockmarks. A comparatively large number of irregular holes occurs in the shallow inner parts of the fjord, off the abandoned mining settlement Pyramiden. These holes might reflect the impact of anchors rather than being pockmarks. In the inner eastern parts, off the glacier Nordenskiöldbreen, a marked decrease in water depth occurs along a relatively sharp line. This marked change is presumably the result of different bedrock compositions – metamorphic rocks in the shallow part and sedimentary rocks in the deeper parts (see Dallmann et al., 2004). Fjord-parallel lineations overlain by minor ridges perpendicular to the fjord axis occur in the shallow area. Whereas the lineations may have been formed subglacially during a glacier advance could the minor ridges be morainal banks being deposited during the glacier retreat (compare with Ottesen & Dowdeswell, 2006). 9. References Dallmann, W.K., Piepjohn, K. & Blomeier, D., 2004. Geological map of Billefjorden – Central Spitsbergen, Svalbard – with geological excursion guide. Norsk Polarinstitutt Temakart Nr. 36. Korsun, S. & Hald, M., 2000. Seasonal dynamics of benthic foraminifera in a glacially fed fjord of Svalbard, European Arctic. Journal of Foraminiferal Research 30(4), 251-271. Ottesen, D. & Dowdeswell, J.A., 2006. Assemblages of submarine landforms produced by tidewater glaciers in Svalbard. Journal of Geophysical Research 111, F01016, doi: 10.1029/2005JF000330


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10. Tables of collected data

Station Date Time (UTC) Location Latitude [N] Longitude [E] Water depth [m]

JM06-169-CTDT 08/03/2006 2036 Billefjorden 78°38.94’ 016°38.54’ 170

JM06-175-CTDT 08/04/2006 0947 Sassenfjorden 78°21.59’ 016°27.73’ 64

JM06-177-CTDT 08/04/2006 1256 Sassenfjorden 78°22.07’ 016°39.92’ 93

JM06-179-CTDT 08/04/2006 1348 Sassenfjorden/Tempelfjorden 78°22.02’ 016°50.94’ 101

JM06-181-CTDT 08/04/2006 1546 Tempelfjorden 78°23.34’ 016°58.57’ 93





JM06-192-CTDT 08/04/2006 2232 Billefjorden 78°31.65’ 016°11.21’ 203

JM06-196-CTDT 08/05/2006 1158 Ymerbukta 78°13.96’ 013°58.83’ 97

JM06-198-CTDT 08/05/2006 1450 Trygghamna 78°13.22’ 013°52.53’ 151

JM06-201-CTDT 08/05/2006 1823 Isfjorden 78°25.92’ 015°47.37’ 224

Table 1: Conductivity-temperature-depth-transmissivity stations.


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Station Date Time

(UTC) Location Latitude [N] Longitude [E]

Water depth [m]

Penetra-tion [m]

Recovery [m] Comment

JM06-171-GC 08/04/07 0606 Isfjorden 78°27.11’ 016°00.97’ 102 ~4 Empty

JM006-172-GC 08/04/07 0644 Isfjorden 78°27.19’ 016°00.96’ 116 >6 Empty

JM06-173-GC 08/04/07 0718 Isfjorden 78°27.18’ 016°01.07’ 118 >6 2.62 Core catcher & core

cutter samples

JM06-176-GC 08/04/07 1216 Sassen-fjorden

78°21.54’ 016°28.52’ 60 ? ~2.20

Samples from 1.00 and 2.00 m for biogeochemical analyses; rest

removed

JM06-200-GC 08/05/07 1658 Isfjorden 78°20.66’ 015°17.85’ 256 ~7 3.73

Table 2: Gravity-corer stations.

Station Date Time (UTC) Location Latitude [N]

Long. [E] Water

depth [m]Penetra-tion [m]

Recovery [m] Comment

JM06-174-PC 08/04/07 0820 Isfjorden 78°26.76’ 015°53.50’ 167 ~8 5.54

JM06-194-PC 08/05/07 0712 Isfjorden 78°22.89’ 015°41.34’ 182 ~6 2.82

The corer seems to have “penetrated” 6 metres on only one side – tipped over?

Core-catcher sample; Core-cutter sample – including bedrock?

JM06-195-PC 08/05/07 0907 Isfjorden 78°20.57’ 015°18.13’ 256 >12 9.63 Core catcher & core

cutter samples

JM06-197-PC 08/05/07 1210 Ymerbukta 78°20.66’ 015°17.85’ 256 ~7 3.73

Table 3: Piston-corer stations.


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Station Date Time (UTC) Location Latitude [N] Longitude [E] Water depth [m]

JM06-176-BC 08/04/2006 1216 Sassenfjorden 78°21.54’ 016°28.52’ 60


JM06-180-BC 08/04/2006 ~1500 Sassenfjorden/Tempelfjorden 78°22.02’ 016°50.94’ 101

JM06-182-BC 08/04/2006 1556 Tempelfjorden 78°23.34’ 016°58.97’ 88






JM06-199-BC 08/05/2006 1512 Trygghamna 78°13.13’ 013°53.44’ 162

Table 4: Box-corer stations.

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