The upper Bashkirian-upper Moscovian succession on Bjornoya and in well 7120/2-1 from the Loppa High is composed of stacked high frequency, fourth- order cycles of mixed siliciclastics and carbonates. Four different types of cycles have been distinguished: conglomerate-dominated cycles are 5-10 m thick and characterised by conglomerates and shallow marine sandstones and they form close to tectonically active highs. Sandstone-dominated cycles are 5-15 m thick, and are composed of mixed sandstone, carbonate and shale in the lower, transgressive part whereas the succeeding regressive part consists of a coarsening- and shalllowing-upward sandstone succession. They characterise open platforms with a moderate supply of siliciclastic material whereas siltstone-dominated cycles formed in protected areas with limited siliclastic supply. Carbonate-dominated cycles consist of a basal bioturbated wackestone overlain by biogenic packstones and grainstones. Most cycles are terminated by microkarstic surfaces.
|Titel||Sequence stratigraphy - concepts and applications|
|Redaktører||F.M. Gradstein, K.O. Sandvik, N.J. Milton|
|Status||Udgivet - 1995|
- Programområde 3: Energiressourcer