| Summary: | Seismic imaging techniques provide a unique means of seeing deep marine large scale geological features. 2D seismic data has been used to describe the geological evolution of an area in the Southwest Barents Sea. The Barents Sea Shelf is located in northern most Europe and extends from the North Atlantic and the Svalbard Archipelago in the west to Novaya Zemlya in the east, over a distance of 1000 km. It is possible to separate three main periods within the geological evolution of the Barents Sea. 1) Palaeozoic period ranging from 542.0ma – 251.0ma. During the late Palaeozoic times most of the Barents Sea was affected by crustal extension (Fig. 2), and a 300km wide rift zone, extending at least 600km northeast was established as a direct continuation of the northeast Atlantic rift between Greenland and Norway 2) Palaeozoic – Mesozoic boundary period ranging from 299.0ma – 199.6ma. The Mesozoic is characterised by regional subsidence, rifting and platform uplift. 3) Cenozoic from 65.5ma to events that are occurring in the present day. This is characterised by a sheared margin and post glacial uplift. Columnar diapirs created by the amounts of available salt equalling the rate of deposited sediment have formed. The source salt is located deep within the Palaeozoic rocks but has pierced its way through the overburden, through active and passive diaprism. The salt diapirs have formed a salt wall like structure around the centre of the study area with a northwest – southeast orientation. One of the main features within the continental shelf stratigraphy is marine slides. As would be expected it is possible to see clear extensional and compressional units within the structure of the slides. The likely trigger for such events is seismic activity. Earthquakes of varying magnitudes have been detected over many years of observations many of which are only detectable through instrumentation. The topography of the shore line in relation to sea level change leads points to a classification of lowstand normal regression where the rates of progradation decrease with time and the rates of aggradation increase with time. These changes in sea level have obviously had some effect on the sediments along the continental shelf. Sedimentation has been affected and the formation of submarine fans has occurred. Faculty of Science and Technology
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