Sedimentation and basin evolution along the Mesozoic margin of western North America

Abstract

During the Mesozoic, the western, or Cordilleran, margin of North America was dominated by convergent plate tectonics. Sedimentary basins within and peripheral to this margin developed in a variety of tectonic settings (Dickinson, 1976a) and contain basin-fill sequences that reflect the complex interplay of basin margin (and interior) tectonism, erosion, basin subsidence, sedimentation, eustasy, and climate. Along this margin, large and small lithospheric plates interacted in a zone of subduction, oblique convergence, and terrane accretion that affected the interior of the North American plate far to the east. Accretion and lateral strikeslip segmentation and dispersal of primarily composite intra-oceanic island-arc terranes during the Mesozoic along different segments of the continental margin — i.e., Sonomia in the Early Triassic (Sonoma orogeny); Stikinia in the Late Jurassic; Klamath-western Sierra Nevada terrane in the Late Jurassic (Nevadan orogeny); and the Alexander-Wrangellia-Peninsular composite terrane in the mid- to Late Cretaceous — produced regionally diverse evolutionary histories (Howell and others, 1985, 1987).