Precambrian: Conterminous U.S.
Precambrian: Conterminous U.S.

Author: John C. Reed, Jr.

Publisher: Geological Society of America

Published: 1993

Total Pages: 752

ISBN-13: 081375447X

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This wide-ranging discussion of Precambrian rocks includes contributions from a diverse array of authors actively engaged in investigations of various aspects of U.S. Precambrian geology. Summary discussions by the editors of the five major chapters place these contributions in a logical regional framework.

Basement Tectonics 8
Basement Tectonics 8

Author: Mervin J. Bartholomew

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 729

ISBN-13: 9401116148

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The 8th International Conference on Basement Tectonics was held in Butte, Montana, August 8-12,1988. Historically, basement tectonics conferences have focused on such topics as reactivation of faults, the influence of basement faults on metallogeny and hyrocarbon accumulation, and the use of geophysical and remote sensing techniques to interpret subsurface and surface geology. The 8th Conference diverged from past conferences in that a unifying theme was selected. Because ancient major terrane or cratonic boundaries are often postulated to be fault zones which are subsequently reactivated, the conference was organized to examine all aspects of ancient continental margins and terrane boundaries and to compare younger (Mesozoic) ones, about which more is known, with older (Paleozoic and Precambrian) ones. Moreover, because the 8th Conference was held in the northwestern United States, a greater emphasis was placed on the Mesozoic margin of western North America and the North American shield. The seven oral sessions and four poster sessions all dealt with aspects of the conference theme: characterization and comparison of ancient continental margins. The organizers extend their thanks to those individuals who graciously consented to serve as moderators for the oral sessions: John M. Bartley, Mark S. Gettings, M. Charles Gilbert, John M. Guilbert, Donald W. Hyndman, William P. Leeman, Robert Mason, and A. Krishna Sinha. The program with abstracts volume was prepared by S. E. Lewis and M. J. Bartholomew.

Early Precambrian Basic Magmatism
Early Precambrian Basic Magmatism

Author: R.P. Hall

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 498

ISBN-13: 9400903995

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Basic magmatic rocks make up approximately three-quarters of the crust ofthe present day Earth. Because we can observe and study the volcanic products of present day tectonic regimes comprehensively, we can shed light on ancient tectono-magmatic provinces, and thereby deduce the petrogenesis and evolution of the oldest basic rocks. This is the primary objective of this book. The book was conceived in order to provide a comprehensive review of the basic rocks produced during the first half of the Precambrian, i.e. the Archaean and early Proterozoic, to about 1.8 Ga years ago. Two major questions are addressed. First, what basic magmas were generated during the early Precambrian: were these magmas globally uniform, and to what extent were prevailing tectonic controls and compo sitions analogous to those of the present day? Clearly, this can be answered only by bringing together fundamental information about all relevant basic magmatic events. Second, is there any systematic temporal variation in the nature of basic suites, and what implications might such variations have on our interpretations of early Earth history? Are there important differences between early Archaean, late Archaean, Proterozoic and modern basic magmatic suites? The book uses two approaches to address these questions. Early chapters examine the fundamental characteristics of these basic rocks, whilst later chapters assess regional distribution and development by providing an overview of each major early Precambrian craton.