MAJOR ADVANCES IN SILICICLASTIC SEDIMENTARY GEOLOGY, 1960-2012: PETROLOGY

The past half-century of work in siliciclastic petrology has benefited from a broad consensus on classifications for sandstones and limestones that provided clarity on the roles of detrital and diagenetic components in compositional heterogeneity. Many key advances in provenance studies and diagenetic investigations have sprung from application of microanalytical tools for imaging and analysis of elements and isotopes. A petrographically-based appreciation of the role of pervasive non-equilibrium and chemical kinetics provides the underpinning of current capabilities to make predictions of siliciclastic rock properties in the subsurface, an endeavor that creates strong links between siliciclastic petrology and the global petroleum industry. Community consensus has yet to converge on classification of fine-grained siliciclastic rocks (shales, mudrocks, mudstones), but the compelling need to make predictions for rock properties in unconventional reservoirs is presently driving much research directed to understanding the causes of heterogeneity this great class of sedimentary materials.