Cordilleran cratonal-miogeoclinal hinge zone in the Mojave Desert and southern Great Basin: What is it How can it be recognized Where is it
- CSUF, Fullerton, CA (United States). Dept. of Geological Sciences
- Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Dept. of Geological Sciences
Commonly referred to as hingelines, ancient cratonal-miogeoclinal transitions are best defined by rift-related structures because during the rift-to-drift history of continental margins, hingelines exert their most profound influences as active tectonic and physiographic features. Where rift-related structures are not preserved, stratigraphic development, as the most direct response to early continental margin tectonic activity, is the more sensitive indicator of paleotectonic setting. Accordingly, it is the initial, Neoproterozoic-Early Cambrian basement-cover deposits of the evolving southwestern US Cordilleran passive margin that provide the clear signature of cratonal-miogeoclinal affinity and hinge definition. At a facies scale, the similarities between cratonal and miogeoclinal strata are compelling; thus the major difference between the craton and miogeocline expressed not by lithofacies, but by stratigraphic unit representation and thickness. Throughout the eastern Mojave Desert and southern Great Basin regions, three distinct expressions of Upper Proterozoic-Lower Cambrian stratigraphic unit representation and thickness relate to hinge definition and location. Basal cratonal stratigraphic sections begin with middle member Wood Canyon Formation that rests nonconformably on Proterozoic basement. Basal miogeoclinal stratigraphic sections are typified by a kilometers-thick sub-Wood Canyon Formation interval ([+-]Pahrump Group; Noonday Dolomite, Johnnie Formation, Stirling Quartzite) and the presence of lower member Wood Canyon Formation. A third, transitional stratigraphic succession begins with a comparatively thin, poorly developed sub-Wood Canyon Formation interval and contains no lower member Wood Canyon Formation. This transitional stratigraphic style represents a craton-margin setting and is crucial for constraining a hinge.
- OSTI ID:
- 5436645
- Report Number(s):
- CONF-9305259-; CODEN: GAAPBC
- Journal Information:
- Geological Society of America, Abstracts with Programs; (United States), Vol. 25:5; Conference: 89. annual meeting of the Cordilleran Section and the 46th annual meeting of the Rocky Mountain Section of the Geological Society of America (GSA), Reno, NV (United States), 19-21 May 1993; ISSN 0016-7592
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
CALIFORNIA
RIFT ZONES
NEVADA
GEOLOGY
CAMBRIAN PERIOD
CONTINENTAL MARGIN
GEOLOGIC FAULTS
GEOLOGIC FORMATIONS
GEOLOGIC HISTORY
GEOLOGIC MODELS
GEOMETRY
GREAT BASIN
PLATE TECTONICS
STRATIGRAPHY
DEVELOPED COUNTRIES
GEOLOGIC AGES
GEOLOGIC FRACTURES
GEOLOGIC STRUCTURES
MATHEMATICS
NORTH AMERICA
PALEOZOIC ERA
TECTONICS
USA
580000* - Geosciences