CRUISE REPORT MARINE-GEOLOGICAL CRUISE TO WEST SPITSBERGEN FJORDS R/V ”Jan Mayen” at Kullkaia in Longyearbyen on August 6th 2006; Foto: M. Forwick on R/V Jan Mayen, August 3rd – August 6th 2006 by Matthias Forwick DEPARTMENT OF GEOLOGY, UNIVERSITY OF TROMSØ, N-9037 TROMSØ, NORWAY 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. 2 Cruise report – West Spitsbergen fjords, August 2006 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). 3 Cruise report – West Spitsbergen fjords, August 2006 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. 4 Cruise report – West Spitsbergen fjords, August 2006 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 5 Cruise report – West Spitsbergen fjords, August 2006 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 6 Cruise report – West Spitsbergen fjords, August 2006 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. 7 Cruise report – West Spitsbergen fjords, August 2006 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.