Tectonic history of the eastern edge of the Alexander Terrane, southeast Alaska
Article Abstract:
Mid-Cretaceous Coast Plutonic rocks in southeast Alsaka show that the tectonic boundary between the Insular (Alexander) and Intermontane composite terranes is overprinted by and imbricate thrust belt. Metamorphosed strata of the Taku terrane overlies the 15 km-thick Gravina sequence, which in turn overlies the Alexander terrane. The sequence overlappedthe Insular-Intermontane boundary through west-vergent thrusting that was coeval with arc volcanism. Deformation occurred between 113 Ma and 89 Ma in twoepisodes concurrent with the emplacement of large sill-like plutons.
Publication Name: Tectonics
Subject: Earth sciences
ISSN: 0278-7407
Year: 1992
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Upper Jurassic-Lower Cretaceous basinal strata along the Cordilleran margin: implications for the accretionary history of the Alexander-Wrangellia-Peninsular terrane
Article Abstract:
Basinal layers from the Upper Jurassic to the Lower Cretaceous are preserved in an interrupted array along the periphery of the Alexander-Wrangellia-Peninsular (AWP) terrane. Turbiditic strata deposited from the Oxfordian to the Albian time were found in nearly all the sedimentary structures. The presence of igneous rocks and volcanic ash in the assemblages is suggestive of deposition at or near to coeval arcs. A geologic scenario explaining the evolution of the assemblages is presented.
Publication Name: Tectonics
Subject: Earth sciences
ISSN: 0278-7407
Year: 1992
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GPS-determination of along-strike variation in Cascadia margin kinematics: implications for relative plate motion, subduction zone coupling, and permanent deformation
Article Abstract:
Research is presented concerning the investigation of the along-strike variation which can be found in the Cascadia margin kinematics through the use of high-precision Global Positioning System geodesy.
Publication Name: Tectonics
Subject: Earth sciences
ISSN: 0278-7407
Year: 2001
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