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The AAPG/Datapages Combined Publications Database

AAPG Bulletin

Abstract


Volume: 64 (1980)

Issue: 5. (May)

First Page: 769

Last Page: 769

Title: Shale--an Overview: ABSTRACT

Author(s): Wayne A. Pryor, Paul Edwin Potter, J. Barry Maynard

Article Type: Meeting abstract

Abstract:

Shale and mud form at least 60% of the world's sediments, have been deposited throughout geologic history, and occur in every major depositional basin. They are major source beds for hydrocarbons, hosts for metallic minerals, sources of ceramic materials, cause of unstable foundation conditions, and precursors of soils that produce our food. Yet the study of shales has lagged far behind that of other sedimentary rocks. Factors that have retarded the study of shales are: (1) we are presently unable to isolate, study, and deduce the histories of the single particles that form shales. Consequently we have had to rely on bulk properties which are based on the average of many particles of diverse origin; these combine the effects of source area, depositional environment, and p st-depositional change; (2) we fail to recognize and interpret in shale the equivalents of the "vertical profiles" that have been so successful in the study of sandstones and carbonate rocks. Such sequences for shales should be based on the vertical variation of bedding, on bioturbation and fossils, and on the amount and type of organic matter. These properties most closely reflect primary depositional processes; (3) we rarely have an idea of the paleocurrent or paleocirculation system of most shaly basins; (4) finally, we have not integrated our present knowledge of shales with the geometry of shale bodies nor has it been common to study the associated lithologies, bounding contacts, and positions of shale bodies within basins.

These factors, and others that will emerge, appear to be the directions in the future sedimentologic studies and interpretations of shaly basins.

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