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Hilde B. Johannessen, University of Tromsų (Norway)
Jan Sverre Laberg, University of Tromsų (Norway)
Matthias Forwick, University of Tromsų (Norway)
Tore O. Vorren, University of Tromsų (Norway)
Haflidi Haflidason, University of Bergen (Norway)
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Offshore Norway turbidites are important hydrocarbon reservoirs in the Cretaceous and Cenozoic succession, and the Andøya - Lofoten system serves as a modern analogue. Two piston cores have been retrieved from this modern turbidite system in the Norwegian Sea. The Andøya Canyon is a pronounced feature on the North-Norwegian continental margin with a length of about 40 km and it represents a continental slope incision of up to 1100 m. The deep-sea channel is ∼ 30 m deep and ∼ 3 km wide. It continues from the canyon mouth and 200 km into the deepest part of the Lofoten Basin.
Core GS07-148-26 PC is 10 m long. It was raised from the depositional lobe at the mouth of the Lofoten Basin Channel, located in the deepest part of the Lofoten Basin at about 3200 m water depth. Seven lithological units have been identified as preliminary results based on MSCL-logging, X-ray photographs and visual description. The basal unit 1 comprises c. 3 m of massive mud. It is overlain by two massive, normal graded units, 3 m (unit 2) and 1 m thick (unit 3). Unit 4 comprises 0.5 m of silty mud overlain by a 0.5 m thick unit (unit 5) of massive, structureless medium-fine sand. The next meter consist of a silty mud with parallel lamination (unit 6) and the upper 1.5 m thick unit 7 comprises muddy sediments. The unit boundaries are sharp and well defined. Based on the normal grading, massive character and well defined boundaries we infer that the sandy units 2, 3 and 5 are turbidites corresponding to Division A in the Bouma sequence. The massive muddy units (unit 1 and 7) and the silty mud (unit 4) represent hemipelagic sediments and are correlated to Bouma Division E while the silty mud with parallel lamination (unit 6) corresponds with Division D.
Future works aims to establish the volume, lateral extent and detailed textures and structures of the turbidites.
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