DEPOSITIONAL EVOLUTION OF LOWER PERMIAN PALAEOAPLYSINA BUILD-UPS, KAPP-DUNER FORMATION, BJORNOYA, ARCTIC NORWAY

The Lower Permian Kapp Duner Formation on Bjomoya includes an approxim ately 45 m thick Palaeoaplysina build-up complex. This complex is comp osed of stacked cycles of thin (0-1 m thick) restricted shelf mudstone s and thicker (<10 m thick) build-ups of Palaeoaplysina wackestone to boundstone capped by subaerial exposure surfaces. In the lower part of the complex, the build-ups are tabular and laterally more widespread than the lenticular build-ups found in the upper part of the complex. The depositional cycles most likely formed in response to fourth-order glacio-eustatic fluctuations in sea level, while the history of the b uild-up complex is controlled by longer-term, third-order fluctuations in relative sea level. The position of the build-up complex is struct urally controlled.