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.

Geology of the Precambrian Superior and Grenville Provinces and Precambian Fossils in North America
Geology of the Precambrian Superior and Grenville Provinces and Precambian Fossils in North America

Author: S.B. Lucas

Publisher: Geological Society of America

Published: 1998

Total Pages: 395

ISBN-13: 0813754461

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This volume contains a description of the geology and mineral deposits of the Superior Province of the Canadian Shield, an overview of Grenville Province geology, and a synopsis of Precambrian fossil occurrences in North America. Six large plates include a geological map of Canada, geological map of the Grenville Province, lithotectonic map of the Superior Province, Archean mineral deposit map of the Superior Province, and more.

Supercontinent Cycles Through Earth History
Supercontinent Cycles Through Earth History

Author: Z.X. Li

Publisher: Geological Society of London

Published: 2016-05-20

Total Pages: 298

ISBN-13: 1862397333

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The supercontinent-cycle hypothesis attributes planetary-scale episodic tectonic events to an intrinsic self-organizing mode of mantle convection, governed by the buoyancy of continental lithosphere that resists subduction during the closure of old ocean basins, and the consequent reorganization of mantle convection cells leading to the opening of new ocean basins. Characteristic timescales of the cycle are typically 500 to 700 million years. Proposed spatial patterns of cyclicity range from hemispheric (introversion) to antipodal (extroversion), to precisely between those end members (orthoversion). Advances in our understanding can arise from theoretical or numerical modelling, primary data acquisition relevant to continental reconstructions, and spatiotemporal correlations between plate kinematics, geodynamic events and palaeoenvironmental history. The palaeogeographic record of supercontinental tectonics on Earth is still under development. The contributions in this Special Publication provide snapshots in time of these investigations and indicate that Earth’s palaeogeographic record incorporates elements of all three end-member spatial patterns.

High-strain Zones
High-strain Zones

Author: Geological Society of London

Publisher: Geological Society of London

Published: 2005

Total Pages: 474

ISBN-13: 9781862391789

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This collection of research and review papers addresses the question of structural evolution during deformation to high strains and the physical properties of rocks that have been affected by high-strain zones. The discussions range from natural examples at outcrop to microscopic studies. They include experiments and numerical models based on the active processes in high-strain zones as well as studies on the physical properties of highly strained rocks in the field and laboratory. Specific questions addressed include magnetotelluric imaging of faults, magnetic fabrics, fabric development, seismic properties of highly strained rocks, change of rheology with strain, influence of melt on the localization of deformation, the relationship between deformation and metamorphism as well as new methods in the analysis of deformation. The book is aimed at an interdisciplinary group of readers interested in the effects of high strain in rocks.

Pre-Mesozoic Ice Ages
Pre-Mesozoic Ice Ages

Author: John C. Crowell

Publisher: Geological Society of America

Published: 1999-01-01

Total Pages: 126

ISBN-13: 9780813711928

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Ancient ice ages are revealed by distinctive stratal facies that tell us much about the times of coolness and how the climate system works. Several strong ice ages were recorded in the late Paleozic time and during transitions from the Devonian in to the Carboniferous and from the Ordovician in to the Silurian. In Precambrian time, several are documented for both the late and early Proterozoic age. This title explores findings on the pre-Mesozoic ice ages, examining climate in relation to tectonobiogeochemical activities rooted in the changing earth-air-ocean system.