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Synthesis of the Seismic Structure of the Greater Alaska Region: Continental Lithosphere
  • +4
  • Xiaotao Yang,
  • Michael Everett Mann,
  • Karen Fischer,
  • Margarete Jadamec,
  • S Shawn Wei,
  • Gary Pavlis,
  • Andrew Schaeffer
Xiaotao Yang
Department of Earth, Atmospheric, and Planetary Sciences, Purdue University

Corresponding Author:[email protected]

Author Profile
Michael Everett Mann
Department of Earth, Environmental, and Planetary Sciences, Brown University
Karen Fischer
Department of Earth, Environmental, and Planetary Sciences, Brown University
Margarete Jadamec
Institute for Artificial Intelligence and Data Science, University at Buffalo, SUNY, Department of Geology, University at Buffalo, SUNY
S Shawn Wei
Department of Earth and Environmental Sciences, Michigan State University
Gary Pavlis
Department of Earth and Atmospheric Sciences, Indiana University Bloomington
Andrew Schaeffer
Geological Survey of Canada Pacific Division, Sidney Subdivision, Natural Resources Canada

Abstract

Significant advances have been made over the last two decades in constraining the structure of the continental lithosphere in Alaska, particularly with the EarthScope USArray seismic data collection efforts. This paper distills recent seismic models in Alaska and western Yukon (Canada) and relates them to major faults and tectonic terranes. We synthesize results from eight shear-wave velocity models and seven crustal thickness models. Through objective clustering of seismic velocity profiles, we identify six different velocity domains, separately for the crust (at the depth range of 10-50 km) and the mantle (at the depth range of 40-120 km). The crustal seismic domains show strong correlations with average crustal thickness patterns and the distribution of major faults and tectonic terranes. The mantle seismic velocity domains demonstrate signatures of major faults and tectonic terranes in northern Alaska while in southern Alaska the domains are primarily controlled by the geometry of the subducting lithosphere. The results of this study have significant implications for the tectonics and geodynamics of the overriding continental lithosphere from the margin to the interior. This synthesis will be of interest to future studies of Alaska as well as other modern and ancient systems involving convergent margins and terrane accretions.
09 Feb 2023Submitted to ESS Books
13 Feb 2023Published in ESS Books