The facies distribution in the Wegener Halvø Formation carbonate platforms along the margins of the Jameson Land Basin is controlled by the topography of an underlying karst surface. Shallow water facies are confined to palaeo-topographic highs; they include algal stromatolites, algal cementstone, oolitic grainstone, bivalve grainstone, bryozoan cementstone, bryozoan-foraminifer boundstone and calcitized evaporite. Deeper water facies were deposited in palaeo-topographic low like fluvial incised valleys and karst sink holes, and in basinal areas; they include various types of resedimented carbonate, bedded evaporite and black shale. Early diagenesis involved pervasive marine cementation by aragonite and high-Mg calcite followed by extensive fresh water dissolution during subaerial exposure. Late diagenesis is dominated by ferroan calcite associated with locally abundant baryte, quartz, galena and fluorite. It post-date hydrocarbon migration.