STEMMERIK, LARS
Geological Survey of Denmark and Greenland, Copenhagen, Denmark

Abstract: Controls on Stacked Upper Carboniferous Carbonate Buildups, Southern Amdrup Land, North Greenland

The Upper Carboniferous succession in northern Greenland is dominated by cyclic shelf siliciclastics and carbonates that formed in response to high frequency and high amplitude sea-level fluctuations. Carbonate buildups are rare, possibly due to lack of accommodation space. They are restricted to Kap Jungersen in southern Amdrup Land where stacked buildups form the foundation for small, up to 100m thick carbonate platforms. These platforms are located in areas characterised by increased subsidence rates due to syn-depositional flexuring.

Individual buildups are rarely more than 30m thick and a few hundred metres wide. Along the platform margin they stack to form up to 100m thick buildup-dominated successions Two types of buildups are volumetrically important. Those composed of bryozoan cementstone often form small isolated mounds surrounded by crinoid- and brachiopod-rich wackestones. Algal-dominated buildups are larger and often surrounded by thick prograding units of bioclastic grainstones. They form the foundation of carbonate platforms and are common along the platform margin.

Both types of buildups are dolomitised and form good potential reservoirs. The stacked buildups are of seismic scale and seismic modelling shows that they form good analogues to the Upper Carboniferous carbonates in the western Barents Sea.

AAPG Search and Discovery Article #90928©1999 AAPG Annual Convention, San Antonio, Texas