SUBJECT
Title
Diagenesis
Type of instruction
lecture
Level
master
Faculty
Part of degree program
Credits
2
Recommended in
Semester 2
Typically offered in
Spring semester
Course description
- Definitions. Diagenetic realms, origin of diagenetic fluids. Basic physical and chemical processes of diagenesis
- Carbonate diagenesis. Shallow-water realm: The island-hydrological model. Diagenesis on the sea-floor, in the meteoric and in the mixing zone. Paleokarst features. Diagnostic cement types. Diagenesis in the deep-sea. Hardgrounds. Deep-burial (physical and chemical compaction burial-cements, cement-chemistry, cement-stratigraphy)
- Diagenesis of coarse-grained clastic sediments. Porosity evolution, pressure solution, quartz-cementation, authigenic clay minerals in sandstones. Secondary porosity. Reservoir implications.
- Diagenesis of clays. Mineralogical changes during burial. Role and fate of mixed-layer clay minerals during burial. The relationship of clay diagenesis, petroleum generation and primary migration of hydrocarbons. Brief recapitulation of the principles of diagenesis of OM. Stages of OM diagenesis as related to the diagenetic realms. Telogenesis and bacterially enhanced degradation of hydrocarbons.
- Dolomitization (early-, burial- and telogenetic)
- Diagenesis of siliceous sediments. Lithification of organic and inorganic silica. Diagenesis lagoonal and lacustrine silica. Silcretes (=pedogenic accumulations of silica)
- Diagenesis of complex basin-fills in actively subsiding and in inverted sedimentary basins.
Readings
- McIllreath, I.A. & Morrow, D.W. (1990): Diagenesis. Geol. Assoc. Canada, Toronto
- Berner, R.A. (1980): Early Diagenesis – A Theoretical Approach, Princeton
- Larsen, G.& Chilingar, G.V.(1979): Diagenesis in sediments and sedimentary rocks. Elsevier