Petrology and Diagenesis of Jurassic Sandstones from Norwegian Danish Basin, North Sea

Abstract

Study of Middle and Upper Jurassic deltaic clastic rocks in thin section, by SEM (scanning electron microscopy) and X-ray diffraction shows that the sandstones and siltstones are made up mainly of immature, poorly sorted material derived from metamorphic and probably pre-Permian volcanic rocks. The first postdepositional cement was quartz followed by kaolinite and calcite. During a later diagenetic stage, minor amounts of kaolinite were formed from alteration of feldspar by pore water.