Four truths about holes in sandstone underlie current research and unsolved problems of sandstone diagenesis. First, primary intergranular porosity and permeability of sand are greatly reduced and subject to total destruction in the early stages of burial diagenesis. Compaction, cementation, recrystallization, and replacement are widely recognized porosity-reducing mechanisms. Rate of porosity loss with depth is related mainly to original sand composition.
Second, at later stages of diagenesis, secondary porosity can be produced by dissolution, of detrital and authigenic minerals. Porosity can be restored and enhanced at depth. Porosity of many major hydrocarbon reservoirs is mainly secondary, a fact just...
Figures & Tables
Aspects of Diagenesis
There are a number of gaping holes in accumulated knowledge within the discipline of sedimentology. Perhaps one of the largest holes has been the general subject of diagenesis in clastic rocks. It was therefore fortuitous that two symposia covering various aspects of diagenesis (mainly in clastics) were presented a year apart in different parts of the country but with the same motivation – to contribute to the closing of that knowledge gap. Sedimentologists now have a fairly good idea of the what and the how of sediment deposition. What happens after the sediments are lithified has frequently been ignored. It was the aim of both editors of this publication to approach the subject from two different viewpoints. Schluger directed a symposium which looked mainly at clastic reservoirs, and Scholle presented a symposium which examined various aspects of paleotemperature control of diagenesis.