UNIVERSITY OF BERGEN REPORT: 100-07/13 Department of Earth Science

Marine Geological and Geophysical Cruise Report from Byfjorden, Herdlefjorden and Salhusfjorden

R/V "HANS BRATTSTRØM" UoB Cruise No. HB-13-184 16. - 20. September 2013

Department of Earth Science University of Bergen, Norway September 2013

Marine Geological and Geophysical Cruise Report

from

Byfjorden, Herdlefjorden and Salhusfjorden

R/V “Hans Brattstrøm” UoB Cruise No. HB-13-184

16. - 20. September 2013

B.O. Hjelstuen D.I. Blindheim M. Andersson & Student Team

i Report 100-07/13 Department of Earth Science University of Bergen (UoB)

Bibliographic reference: Hjelstuen, B.O., Blindheim, D.I., Andersson, M. & Student Team, 2013. Marine Geological and Geophysical Cruise Report from Byfjorden, Herdlefjorden and Salhusfjorden. Report No. 100- 07/13, Department of Earth Science, University of Bergen, Bergen, Norway, 18 pp.

Copyright 2013 by: University of Bergen Department of Earth Science Allegt. 41, N-5007 Bergen, Norway

First Published 2013

ISSN

ii Report 100-07/13 Department of Earth Science University of Bergen (UoB)

CONTENT

1. INTRODUCTION 1 1.1. Objectives 1

1.2. Scientific party 1

2. RESEARCH VESSEL and EQUIPMENT 1

2.1. Research vessel 1

2.2. Equipment 2

3. FIELD OPERATIONS 4

3.1. Weather and sea state conditions 4

3.2. Equipment Performance 5

3.3. General cruise performance 5

Figure 1: Overview map 6 Figure 2: Sub-bottom profile from southern Byfjorden 7 Figure 3: Sub-bottom profile from Herdlefjorden 7 Figure 4: Sub-bottom profile from Salhusfjorden 8 Figure 5: Sub-bottom profile from northern Byfjorden 8 Figure 6: Sub-bottom profile from southern Byfjorden 9 Figure 7: CTD profile from southern Byfjorden 10 Figure 8: CTD profile from Herdlefjorden 11 Figure 9: CTD profile from Salhusfjorden 12 Figure 10: CTD profile from northern Byfjorden 13 Figure 11: CTD profile from southern Byfjorden 14

Table I: General Survey Log 15 Table II: Station Log 16 Table III: Seismic Profiles 17

Appendix A: Student team 18

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1. INTRODUCTION

1.1. Objectives

The marine geological/geophysical cruise to Byfjorden, Herdlefjorden and Salhusfjorden (Fig. 1) was part of the UoB course GEOV108 “Introduction to marine geology and geophysics”. The main objective of the cruise was to introduce students to marine geological/geophysical field work. 58 students participated during the cruise week.

This report will give a short description of the cruise performance. Figure 1 shows the survey area, whereas a general survey log is provided in Table I.

1.2. Scientific Party

Berit O. Hjelstuen UoB1 Cruise leader Dag Inge Blindheim UoB1 Technician Mareile Andersson UoB1 Technician (Thursday and Friday) Student team UoB1 See Appendix A

2. RESEARCH VESSEL and EQUIPMENT

2.1. Research vessel R/V Hans Brattstrøm has a length of 24.3 m, beam of 6.5 m, a displacement of 97 tonnes, and a top speed of 13 knots. The research vessel is owned by the University of Bergen and is operated by the Institute of Marin Research, Bergen. The main duties are research operations within the areas of fishery, environment research, sea-bed sampling and educational surveys for students. The research vessel has a crew of 2, and operates in the coastal areas out to 20 nautical miles from the coast.

------1 UoB: University of Bergen, Dept. of Earth Science, Allegt. 41, 5007 Bergen, Norway

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2.2. Equipment A sub-bottom profiler (SBP), SB-216S from EdgeTech, was used throughout the entire cruise to map the characteristics of the sub-seabed sediments (Figs. 2-6). The profiler operates in the frequency range of 2-16 kHz. The profiler has a theoretical penetration of up to 60 m. The profiler was towed on the starboard side of the vessel, at a level of about 1 m below the sea surface.

Sub-bottom profiler used during the cruise. (Photo: Eva Bjørseth; February 2009)

Throughout the entire cruise a box core was used to collect samples from the upper part of the sediment column (Fig.1; Table II). One sample from each box corer collected were sieved (>1 mm, >0.5 mm, >0.15 mm) onboard. One sample from each location was stored in a plastic box and added Rosa Bengal, for later analyses.

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Box core used during the cruise. (Photo: Eva Bjørseth; February 2009)

CTD profiles were collected in Byfjorden, Salhusfjorden and Herdlefjorden (Figs. 1, 7-11; Table II). The CTD was connected to a winch, and lowered to the seabed before withdrawal.

CTD used on cruise.

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Gravity corer used during the cruise. (Photo: Eva Bjørseth; February 2009)

Gravity cores were collected at five locations (Fig. 1, Table II). A core barrel length of 2 m was used. The gravity cores were split in two and labeled for further analyses at the Department of Earth Science, UiB.

3. FIELD OPERATIONS

The students were divided into five groups and each group had one day onboard the R/V Hans Brattstrøm. Totally, 58 students participated. A summary of the ship-board operations is provided in Table I.

3.1. Weather and sea state conditions The weather conditions during the cruise were generally good for surveying. The sea state was calm, except for Tuesday and Thursday when the waves were about 1 m.

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3.2. Equipment performance

 The chirp was run with success during the entire survey, and the data collected had an overall good quality. The sub-seafloor penetration depended very much on the sediment characteristics. Due to slightly rougher sea state on Tuesday 17. September and Thursday 18. September the acquired data had a lower quality, even though the chirp was tried lowered to a larger depth below the sea surface.

 The box corer functioned well throughout the cruise. Several samples was taken and stored in plastic boxes for further analyses at the Department of Earth Science, UoB. Rosa Bengal was added to these samples. Samples were also sieved onboard, and the fractions were stored in small plastic boxes.

 The gravity coring system was used without any problems. The five gravity cores raised were labeled and transported to the Department of Earth Science, UoB, for further analyses and storage.

 The CTD functioned well throughout the cruise.

3.3. General cruise performance  5 box cores, 5 gravity cores and 5 CTD profiles were collected (Table II).  A total of ca 20 km with seismic profiles were collected (Table III)

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Figure 1. Overview map, showing locations of box cores, gravity cores and CTD stations. Red lines indicate approximate position of chirp profiles.

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Figure 2. Chirp profile from southern part of Byfjorden (16. September 2013).

Figure 3. Chrip profile from Herdlefjorden (17.september 2013).

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Figure 4. Chirp profile from Salhusfjorden (18. September 2013).

Figure 5. Chirp profile from northern part of Byfjorden (19. September 2013).

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Figure 6. Chirp profile from southern part of Byfjorden (20. September 2013).

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Figure 7. CTD profile HB-13-184-01CTD collected in southern part of Byfjorden 16. September 2013. Position in Fig. 1. Red curve is salinity and green curve is temperature.

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Figure 8. CTD profile HB-13-184-02CTD collected in Herdlefjorden 17. September 2013. Position in Fig. 1. Red curve is salinity and green curve is temperature.

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Figure 9. CTD profile HB-13-184-03CTD collected in Salhusfjorden 18. September 2013. Position in Fig. 1. Red curve is salinity and green curve is temperature.

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Figure 10. CTD profile HB-13-184-04CTD collected in northern part of Byfjorden 19. September 2013. Position in Fig. 1. Red curve is salinity and green curve is temperature.

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Figure 11. CTD profile HB-13-184-05CTD collected in southern part of Byfjorden 20. September 2013. Position in Fig. 1. Red curve is salinity and green curve is temperature.

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General Survey log Table I GEOV108 student cruise HB-13-184, R/V Hans Brattstrøm Date Time Subject

16.09.2011 09:00– 11:00 Mobilization at Nykirkekaien. Late start due to inspection of engine 11:00-15:00 Collection of seismic profiles, CTD, box core and gravity core from Byfjorden 15:00 End of day, arriving Nykirkekaien

09:20 Leaving Marineholmen Collection of seismic profiles, CTD, box core and gravity core from 17.09.2011 09:55-13:20 Herdlefjorden 13:45 End of day, arriving Marineholmen

09:15 Leaving Marineholmen Collection of seismic profiles, CTD, box core and gravity core from 09:50:-13:00 18.09.2011 Salhusfjorden 13:40 End of day, arriving Marineholmen.

09:10 Leaving Marineholmen 19.09.2011 10:15-13:00 Collection of seismic profiles, CTD, box core and gravity core from Byfjorden 13:30 End of day, arriving Marineholmen. 09:00 Leaving Nykirkekaien

Collection of seismic profiles, CTD, box core and gravity core from 09:10 10:00-14:00 Leaving Marineholmen Herdlefjorden 20.09.2011 09:45-13:00 Collection of seismic profiles, CTD, box core and gravity core from Byfjorden 14:30 End of day, arriving Nykirkekaien. End of cruise 13:00 End of day, arriving Nykirkekaien. Demobilisation. End of cruise

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Table II Station Log Date Station no Latitude (N) Longitude (E) Location, water depth HB-13-184 -01BC 16.09.2013 1 sample taken and stored in box. 60o 24.736’ 5o 16.402’ Byfjorden, 344 m Added ca. 100 ml Rosa Bengal

16.09.2013 HB-13-184- 01CTD 60o 24.736’ 5o 16.402’ Byfjorden, 346 m

HB-13-184 -01GC 16.09.2013 c. 2.0 m long core sampled. Cut into 60o 24.736’ 5o 16.402’ Byfjorden, 346 m two segments. HB-13-184 -02BC 17.09.2013 1 sample taken and stored in box. 60o 30.420’ 5o 11.525’ Herdlefjorden, 380 m Added ca. 100 ml Bengal Rosa

17.09.2013 HB-13-184-02CTD 60o 30.420’ 5o 11.905’ Herdlefjorden, 380 m

HB-13-184 -02GC 17.09.2013 Ca 2.0 m long core sampled. Cut into 60o 30.420’ 5o 11.905’ Herdlefjorden, 380 m two segments. HB-13-184 -03BC 18.09.2013 1 sample taken and stored in box. 60o 31.178’ 5o 15.615’ Salhusfjorden, 535 m Added ca. 100 ml Rosa Bengal

18.09.2013 HB-13-184-04CTD 60o 31.178’ 5o 15.615’ Salhusfjorden, 535 m

HB-13-184 -04GC 18.09.2013 Ca 2.0 m long core sampled. Cut into 60o 31.178’ 5o 15.615’ Salhusfjorden, 535 m two segments HB-13-184 -04BC 19.09.2013 1 sample taken and stored in box. 60o 27.081’ 5o 15.489’ Byfjorden, 317 m Added ca. 100 ml Rosa Bengal

19.09.2013 HB-13-184-04CTD 60o 27.081’ 5o 15.489’ Byfjorden, 317 m

HB-13-184 -04GC 19.09.2013 2 m long core sampled. Cut into two 60o 27.081’ 5o 15.489’ Byfjorden, 317 m segments, each ca. 1 m long. HB-13-184 -05BC 20.09.2013 1 sample taken and stored in box. 60o 25.661’ 5o 16.554’ Byfjorden, 320 m Added ca. 100 ml Rosa Bengal

20.09.2013 HB-13-184-05CTD 60o 25.661’ 5o 16.554’ Byfjorden, 320 m

HB-13-184 -05GC 20.09.2013 2.0 m long core sampled. Cut into two 60o 25.661’ 5o 16.554’ Byfjorden, 320 m segments, each ca. 1.0 m long.

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Table III Seismic profiles

File name Date Location

BF_linje01A 16.09.13 Byfjorden - south BF_linje01A 16.09.13 Byfjorden - south HF_linje02A 17.09.13 Herdlefjorden HF_linje02B 17.09.13 Herdlefjorden SF_linje03A 18.09.13 Salhusfjorden BF_linje04A.jsf 19.09.13 Byfjorden - north BF_linje05A.jsf 20.09.13 Byfjorden - south BF_linje05B.jsf 20.09.13 Byfjorden - south

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APPENDIX A

Måndag 16. september Aanestad Birgitte Aarsland Ingeborg Aartun Stian Aksland Vegard Arntzen Mariell Valvik Espen Berntzen Amalie Knutsen Valheim Sofie Bakkevig Danielsen Kim-André Tellefsen Karen Dybvig Malene Teigland Zweidorff Julie Lundekvam Tysdag 17.september Furset Anders Gloppen Ole Alexander Haaland Simon Myklebust Hamper Rowan John Dale Caroline Hope Hamre Mathias Hansen Lene Loug Helland Kjersti Sunde Øyvind Larsen Hinna Camilla Husebø Onsdag 18.september Storemark Sondre Straume Veland Torbjørn Østerbø Johnsen Ingrid Stenquist Karlsen Fredrik Hjorth Knutsen Heidi Husebø Kristensen Runar Sherling Ledsaak Karina Storstein Tor Helge Midthun Kristian Rosseid Øygard Ørjan Berge Nilssen Einar Særheim Refvem Marte Aarrestad Sletten Stine Hemnes Torsdag 19.september Norang Ragnhild Lithun Igland Kristoffer Opsal Mari Kleiveland Miljeteig Solfrid Poole Louise Kristiansen Remeijer Jelle Michiel Riiser Ole Sannes Skjelvan Bjørnar Liland Njå Erika Rørvik Solheim Martin Øvretveit Karoline Førland Marthe Fredag 20.september Bendiksen Helle Malene Blækkan Ingvild Dimmen Vilde Hetland Asbjørn Marvik Maria Ordemann Maria Erichsen Vistnes Kjersti Norland Heia Tonje Ågotnes Synne Skaar Holden Nora Grønnevik Håvard

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