223 Origin, Accretion, and Translation of Mesozoic-Cenozoic Terranes along the Pacific Margin of North America

Tuesday, 24 October 2017
1:30 PM - 5:30 PM
Ballroom 6A

GEODYNAMIC CONSTRAINTS ON TERRANE ACCRETION ALONG THE WEST COAST OF NORTH AMERICA

Paper number: 223-3
Program: Technical Sessions
Time: 1:55 PM – 2:15 PM

Authors

  • Lijun Liu Presenting Author
    University of Illinois at Urbana-Champaign, Urbana, IL

Abstract

The accretion of exotic terranes and their translation along the west coast of North America have fundamental implications on the growth of continental crust. Structural geology, paleomagnetic data, and seismic tomography illuminate on this process with variable constraining powers. However, the exact nature and evolution of terrane accretion remain unclear, so does its relationship with Mesozoic-Cenozoic surface geology of North America and with the history of subduction. Here I discuss potential geodynamic constraints on terrane accretion by summarizing recent works on modeling subduction and resulting surface tectonic evolution. In particular, I will focus on 1) possible time windows for terrane accretion, 2) accretion mechanisms involving different subduction polarities, and 3) relevant surface geology records. I attempt to address these questions in the context of past plate motion and subduction, resulting present-day mantle structures, and various surface expressions. Key observational records that may be useful include the continuous westward movement of North America since Early Cretaceous, the Cretaceous-aged Western Interior Seaway (WIS), latest Cretaceous-early Tertiary Laramide orogeny, and present-day complex mantle seismic images beneath North America.

Geological Society of America Abstracts with Programs. Vol. 49, No. 6

doi: 10.1130/abs/2017AM-299855

© Copyright 2017 The Geological Society of America (GSA), all rights reserved. Permission is hereby granted to the author(s) of this abstract to reproduce and distribute it freely, for noncommercial purposes. Permission is hereby granted to any individual scientist to download a single copy of this electronic file and reproduce up to 20 paper copies for noncommercial purposes advancing science and education, including classroom use, providing all reproductions include the complete content shown here, including the author information. All other forms of reproduction and/or transmittal are prohibited without written permission from GSA Copyright Permissions.