ABSTRACT: Karst-Controlled Facies Mosaic in Late Permian Carbonate Platform Sequence, Wegener Halvo Formation, Wegener Halvo, East Greenland

STEMMERIK, LARS, Geological Survey of Greenland, Copenhagen, Denmark, and PETER A. SCHOLLE, Southern Methodist University, Dallas, TX

The Wegener Halvo Formation is a fully marine carbonate platform sequence fringing the Late Permian depositional basin of central East Greenland. In the study area of Wegener Halvo, the rocks overlie an earlier Permian paleokarst terrain with 60-70 m or more of relief. The purpose of this paper is to describe the facies mosaic developed as the sea transgressed this palaeokarst terrain and relate it to fluctuations in relative sea level.

Three distinctly different depositional successions can be distinguished and related to their paleotopographic position: (1) In basinal lowland areas and distal karst valleys, thin transgressive shallow water limestones are overlain by thick deeper water black shales; (2) in narrow karst valleys and areas adjacent to topographic highs, transgressive shallow water limestones are overlain by subordinate black shales and thick piles of resedimented carbonates; (3) on topographic highs, the entire succession is made up of shallow water, often reefal carbonates.

Deposition took place during an overall rise in relative sea level during the Kazanian followed by a marked regression near the Kazanian-Tatarian boundary. Superimposed on this pattern are three shorter term regressive-transgressive events, each corresponding to a depositional sequence. Lateral migration of facies as response to these "minor" fluctuations in relative sea level was limited by the great predepositional relief, and the stacking pattern on the topographic highs is aggradational and interrupted by minor paleokarst surfaces. Lateral progradation occurred mainly during the final regression.

AAPG Search and Discovery Article #91012©1992 AAPG Annual Meeting, Calgary, Alberta, Canada, June 22-25, 1992 (2009)