Imbricate architecture of the Upper Paleozoic to Jurassic oceanic Cache Creek Terrane, central British Columbia

L. C. Struik, P. Schiarizza, M. J. Orchard, F. Cordey, Hiroyoshi Sano, D. G. MacIntyre, H. Lapierre, M. Tardy

Research output: Contribution to journalArticlepeer-review

37 Citations (Scopus)

Abstract

Upper Paleozoic to Lower Jurassic oceanic rocks of the Cache Creek Terrane near Fort St. James, in central British Columbia, form a stack of thrust sheets cut by steeply dipping strike-slip faults. Paleontologically dated upper Paleozoic strata include bioclastic shallow-water limestone and ribbon chert. Isotopically dated Permian rocks consist of tonalite sills and stocks and rhyolite flows intercalated with basalt flows. Paleontologically dated lower Mesozoic rocks include greywacke, sandstone, siltstone, argillite, ribbon chert, conglomerate, limestone, and basalt tuff. Trembleur Ultramafite unit of the Cache Creek Complex, in places part of an ophiolite suite, forms thrust sheets and klippen that overlie lower Mesozoic sedimentary rocks. Sedimentological, lithochemical, paleontological, petrological, and textural comparisons with other areas and established models demonstrate that Cache Creek Terrane is an accretionary complex, a structurally stacked assemblage of rocks that originated in diverse and disparate oceanic paleoenvironments. These environments include spreading ridge, oceanic plateau, atoll, trench fill, and possibly arc. Internal imbrication of the terrane is as young as Early Jurassic, as determined from fossil evidence, and the minimum age of obduction of the thrust stack westward onto Stikine Terrane is Middle Jurassic, as determined from dating of a crosscutting pluton. Triassic blueschist and eclogite of Cache Creek Terrane are interpreted to have been primarily uplifted to upper crustal levels during Triassic subduction. Cache Creek Terrane, as a remnant of that subduction process, and caught in the collision between Stikine and Quesnel terranes, marks the position of a lithosphere-scale suture zone, the Pinchi Suture.

Original languageEnglish
Pages (from-to)495-514
Number of pages20
JournalCanadian Journal of Earth Sciences
Volume38
Issue number4
DOIs
Publication statusPublished - Apr 1 2001

All Science Journal Classification (ASJC) codes

  • Earth and Planetary Sciences(all)

Fingerprint Dive into the research topics of 'Imbricate architecture of the Upper Paleozoic to Jurassic oceanic Cache Creek Terrane, central British Columbia'. Together they form a unique fingerprint.

Cite this