Triassic plutonism in southern California: Southward younging of arc initiation along a truncated continental margin
Article Abstract:
The onset and duration of arc magnetism from the early Mesozoic plutons in the Transverse Ranges and southwestern Mojave Desert region were analyzed by utilizing U-Pb geochronologic methods. Geochronological analysis of Triassic plutons from the Transverse Ranges and western Mojave Desert indicated the presence of an early Mesozoic eastward subduction beneath the southern regions of California. Furthermore, U-Pb dating indicated the presence of an Early Jurassic amagmatic episode which preceded voluminous Middle and Late Jurassic magmatism.
Publication Name: Tectonics
Subject: Earth sciences
ISSN: 0278-7407
Year: 1997
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Jurassic (Tithonian) Radiolaria from La Desiderade (Lesser Antilles): preliminary paleontological and tectonic implications
Article Abstract:
A study was conducted to analyze Jurassic Radiolara fossils found in La Desiderade, Guadaloupe. The fossils were found in bedded, red ribbon cherts and represent the oldest fossils unearthed in the Lesser Antilles. Fossil age analysis invalidates earlier findings of differences for basement ages of the central and eastern parts of the island. Absence of the Jurassic chert in other regions provide basis for the Pacific origin of the samples studied.
Publication Name: Tectonics
Subject: Earth sciences
ISSN: 0278-7407
Year: 1992
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Jurassic tectonic history of the Otago Schist, New Zealand
Article Abstract:
A regional analysis of Otago Schist mesoscopic fabrics show that the schist formed as a result of collision between the Caplesand Torlesse terranes in the Jurassic orogeny. Moreover, schist fabric deformations involve at least two transposition cycles. The tectonic transport direction is dependent on the chosen deformation model, but generally the Caples terrane appears overthrust on the Torlesse terrane.
Publication Name: Tectonics
Subject: Earth sciences
ISSN: 0278-7407
Year: 1993
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