Regional Structure and Stratigraphy of Sierra El Aliso, Central Sonora, Mexico
Author
Bartolini, ClaudioIssue Date
1988Keywords
MexicoSierra El Aliso
Sonora Mexico
stratigraphy
structural geology
tectonics
Geology -- Mexico -- Sierra El Aliso
Geology, Stratigraphic
Geology, Structural -- Mexico -- Sonora (State)
Advisor
Stewart, JohnCommittee Chair
Coney, Peter J.
Metadata
Show full item recordPublisher
The University of Arizona.Rights
Copyright © is held by the author. Digital access to this material is made possible by the Antevs Library, Department of Geosciences, and the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author or the department.Abstract
Assemblages of Paleozoic age and less significant Triassic and possibly Cretaceous-Tertiary volcanic rocks constitute the Sierra El Aliso, 186 km east-southeast of Hermosillo, Sonora. The Paleozoic section consists of approximately 2000 m of allochthonous Ordovician to Permian pelagic and hemipelagic deposits that accumulated in continental slope, continental rise and ocean floor (?) environments. The lower Paleozoic is characterized by graptolitic black shale and radiolarian chert, quartzite, argillite and local limestone. The upper Paleozoic is predominantly turbidite carbonates rich in benthonic foraminifera, and conodont faunas, subordinate bedded chert, siltstone, sandstone and chert-clast conglomerate. After Early Permian time, but prior to the deposition of the Late Triassic Barranca Group the Paleozoic section was imbricated along south-southeast vergent thrust faults. The Triassic rocks unconformably overlie the Paleo-zoic strata and all thrust faults. The Triassic and older rocks are overlain by the Cretaceous-Tertiary volcanics.Type
textThesis-Reproduction (electronic)
Degree Name
M.S.Degree Level
mastersDegree Program
Graduate CollegeGeosciences
Degree Grantor
University of ArizonaCollections
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