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Several sandy turbidites form hydrocarbon reservoirs. Experience has shown that stratigraphic traps in a turbidite system may be difficult to predict. Additional information on sandy turbidite systems can be obtained from the study of modern analogues, as the Andøya Canyon - Lofoten Basin Channel system (Laberg et al., 2005; 2007). This system is located on the continental margin offshore northern Norway. Based on multi-beam bathymetry, side scan sonar records, high-resolution seismic data and cores three morphological elements have been identified: 1) the Andøya Canyon, 2) the Lofoten Basin Channel, and 3) the depositional lobe at the mouth of the channel. The Andøya Canyon represents a 40 km long, up to 10 km wide and 1100 m deep V-formed incision into the continental slope. The canyon displays a very complex morphology including slide scars and gullies due to sediment instability and erosion. The upper canyon acted as a sediment trap routing alongslope bottom-current-transported sediments into the canyon. A c. 200 km long channel, the Lofoten Basin Channel can be followed from the mouth of the canyon at the base of the continental slope into the abyssal plain of the Norwegian Sea. The channel is a rather straight erosional feature, up to 30m deep and 3 km wide. It has poorly developed levees except for in the canyon - channel transitional area where the channel makes a 90o turn due to the basin morphology. Here the right-hand levee is up to 80 m high. The depositional lobe is located at the channel mouth but so far its areal extent is not known. High-resolution sub-bottom profiler records show units of some meter thickness that can be followed for several tens of kilometres. Recent coring has identified up to 4m thick intervals of sand (Johannessen et al., this volume). They are separated by continuous to slightly discontinuous medium to high amplitude reflections. Sediment waves are present at some levels.
Acknowledgement
This work is a contribution to the PETROMAKS program Democen. Financial support from the Research Council of Norway and StatoilHydro is greatly acknowledged.
References
Johannessen, H.B., Laberg, J.S., Forwich, M., Vorren, T.O., Haflidason, H. Sandy turbidites in the Andøya Canyon - Lofoten Basin Channel system, Norwegian Sea. Abstract, IGC33, this session.
Laberg, J.S., Vorren, T.O., Kenyon, N.H., Ivanov, M., Andersen, E.S. 2005. A modern canyon-fed sandy turbidite system of the Norwegian continental margin. Norwegian Journal of Geology 85, 267-277.
Laberg, J.S., Guidard, S., Mienert, J., Vorren, T.O., Haflidason, H., Nygrd, A. 2007. Morphology and morphogenesis of a high-latitude canyon; the Andøya Canyon, Norwegian Sea. Marine Geology 246, 68-85.
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