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Abstract: Detailed geological mapping across the Shuswap metamorphic complex between latitudes 50°00'N and 50°45'N reveals that superstructure forms a semicontinuous carapace across the complex, with minimal evidence of internal thinning. [...]

Abstract: The Aberdeen gneiss complex is composed of complexly deformed migmatitic orthogneiss and paragneiss situated within the core of the Vernon antiform, a structure defined by a series of subparallel [...]

Coherent oceanic strata in the French Range belong to the exotic Cache Creek terrane of the Canadian Cordillera. They were metamorphosed to blueschist grade, tectonicaily extruded, eroded, and intruded by plutons--perhaps in 150 m.y. earlier. Southwest-verging folds and northeast-dipping thrust faults along which the blueschist was emplaced affected the width of the northern Cache Creek terrane and the adjacent Whitehorse Trough. Exhumation is recorded by eclogite clasts and by early Bajocian chert granule deposition in Whitehorse Trough before ca. 171 Ma. Oldest postkinematic plutons require that emplacement-related regional deformation, pluton crystallization, and cooling was complete by ca. 172 Ma. Exhumation may have accelerated upon rupture of Cache Creek oceanic crust as it sobducted between two conjoined arc segments (Stikine and Quesnel) that were rotating into parallelism. Paleogeographic changes are recorded by dramatic arc uplift, paleoflow reversal, and changes in ammonite zonation as the last vestiges of Cache Creek ocean crust became isolated. Blueschist was tectonically extruded over the colliding Stikine arc segment from beneath a backstop of Quesnel arc, which had been accreted to the continental margin by ca. 180 Ma. Keywords: blueschist, Cache Creek, geochronology, structure, radiolarians, microfossils, obduction, exhumation, tectonics.