Late Paleozoic And Mesozoic Tectonic Events In West Central Nevada

Author : Tristan John Ashcroft
Publisher :
ISBN 13 :
Total Pages : 348 pages
Book Rating : 4.:/5 (851 download)

DOWNLOAD NOW!

Download or read book Stratigraphic and Structural Relationships in the Northern Adobe Range, Elko County, Nevada in the Context of Late Paleozoic and Mesozoic Deformation and Tectonics written by Tristan John Ashcroft and published by . This book was released on 2012 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: The northern Adobe Range, Elko County, Nevada, preserves four late Paleozoic deformation events and one Mesozoic deformation event. This significantly revises previous work (Ketner and Ross, 1990) that suggested only Mesozoic deformation is preserved in the northern Adobe Range. The northern Adobe Range exposes an unusually complete succession of Ordovician to Triassic strata and, therefore, is an excellent location to examine the effects of Paleozoic and Mesozoic deformation. The revised timing of deformation in the northern Adobe Range is based on the new interpretation that a number of contacts are unconformities instead of the previous interpretation that those contacts are thrust faults. The four Paleozoic deformation events in the northern Adobe Range are a Mississippian tilting event, a Pennsylvanian southeast verging thrusting event, a late Pennsylvanian folding event, and an Early to Late Permian folding event. The three earlier events are correlative to deformation elsewhere along the Paleozoic Cordilleran margin, most notably to unconformities recognized to the west at Carlin Canyon. The Pennsylvanian southeast verging thrusting event is the major Paleozoic deformation event preserved in the northern Adobe Range and is correlative to late Paleozoic thrusting with similar kinematics elsewhere along the Cordilleran margin. The Early to Late Permian compression was either northeast or southwest directed which is an unusual direction of compression that has not been reported elsewhere. The Mesozoic folding is preserved in both the map scale Adobe syncline and mesoscopic deformation of Triassic strata in the study area. Only one Mesozoic deformation event occurred here in the form of southeast verging folding. Based on regional relationships, this folding occurred either during the Late Jurassic or the Cretaceous. The Late Paleozoic thrusting event in the northern Adobe Range is a component of diachronous thrust faulting along the Cordilleran margin progressing from the Mississippian in the northeast to the Permian in the southwest and may be related to the cause of the Ancestral Rocky Mountain uplifts. Within the constraints of available age control, this thrust faulting is coeval with both the southwestward progression of the Ancestral Rocky Mountain uplifts and the southwestward progression of suturing between Laurentia and Gondwana. These two coeval southwestward progressive compressive regimes, one to the southeast and one to the northeast, may have driven deformation related to the Ancestral Rocky Mountain uplifts in the interior of the Laurentian continent.