Structural Investigations of the Italian Trap Allochthon, Redington Pass, Pima County, Arizona
Author
Benson, Gregory ScottIssue Date
1981Keywords
ArizonaCenozoic
displacements
faults
Italian Trap Allochthon
Mesozoic
metamorphism
Paleozoic
Pima County Arizona
Precambrian
Redington Pass
Santa Catalina-Rincon Metamorphic Core Complex
structural geology
tectonics
tectonite
Tertiary
thrust faults
United States
Rock deformation -- Arizona -- Redington Pass
Geology, Structural -- Arizona -- Redington Pass
Faults (Geology) -- Arizona -- Redington Pass
Committee Chair
Davis, George H.
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.Collection Information
This item is part of the Geosciences Theses collection. It was digitized from a physical copy provided by the Antevs Library, Department of Geosciences, University of Arizona. For more information about items in this collection, please email the Antevs Library, antevs@geo.arizona.edu.Abstract
Italian Trap Allochthon is a rare upper-plate exposure of Paleozoic metasedimentary and Precambrian to Tertiary crystalline tectonites in the Santa Catalina-Rincon metamorphic core complex. Elsewhere in the complex, metasedimentary tectonite is usually restricted to an autochthononous position. The internal structures of the allochthon consist of numerous low-angle faults, tear faults, and overturned asymmetric and upright folds. Close association of the low-angle faults and asymmetric folds, and vergence of the folds, indicates that these folds were formed during westward transport along the low-angle faults. The structures of the allochthon are truncated and rotated to the northeast by a listric (?) normal fault. The probable shape of the fault surface, together with the northeastward rotation of the internal structures, suggests translation of the allochthon from the northeast to the southwest. The fact that metasedimentary tectonites are found in upper- plate position indicates that the listric (?) normal faulting post-dates the metamorphism of the Paleozoic and Mesozoic strata. Metamorphism in turn was part of the development of the Santa Catalina-Rincon metamorphic core complex. It is inferred that the Italian Trap Allochthon was emplaced in the final stages of profound regional extension which prevailed during the mid-Tertiary in southern Arizona.Type
textThesis-Reproduction (electronic)
Degree Name
M.S.Degree Level
mastersDegree Program
Graduate CollegeGeosciences
Degree Grantor
University of ArizonaCollections
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Structural investigations of the Italian Trap Allochthon, Redington Pass, Pima County, ArizonaBenson, Gregory Scott (The University of Arizona., 1981)
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