JURASSIC TO CRETACEOUS STRATIGRAPHY OF SHALLOW CORES ON THE MORE BASIN MARGIN, MID-NORWAY

Four cores drilled by IKU in summer 1988 southwest of Kristiansund at the More Basin Margin close to the Gossa High (6206/02) penetrated mar ginal marine Lower Jurassic coarse elastic and Upper Cretaceous shelf deposits. The lower part of the easternmost core 3 contains Lower Jura ssic matrix-supported terrestrial conglomerates rich in mafic clasts d eposited in an alluvial fan environment. This is succeeded by a clast- supported, partly marine-influenced very coarse gneiss conglomerate of Pliensbachian-Toarcian age, possibly representing fan-delta deposits. Core 2 penetrated a similar clast-supported conglomerate below a more sandy, partly marine influenced unit of Late Toarcian-Aalenian age. C ore 8, further west, and the lower part of core 1 contained similar sa ndy successions of Late Toarcian-Aalenian age deposited in a distal fa n-delta environment. In the latter core there is a major hiatus (some 80 million years) as Upper Toarcian-Aalenian sediments are overlain by Upper Albian Shelf deposits. The Cretaceous succession in the core co ntained marine mudstones, sandstones and shales/claystones of Late Alb ian to Turonian/Santonian ages. Distinct seismic reflections are prese nt in the cored succession, but only those in the Cretaceous sequence can confidently be tied directly to the More Basin based on the availa ble data. A bedrock map of the More Basin Margin is presented.