Document Type

Book Chapter

Publication Date

4-7-2021

Department

Earth Sciences

Language

English

Publication Title

Untangling the Quaternary Period—A Legacy of Stephen C. Porter

Abstract

The Tuya-Kawdy region of northern British Columbia is well established as a place where glaciation and volcanism overlapped in space. However, no modern work has integrated observations from the region’s volcanic and glacial deposits with geochronologic constraints to summarize how they might overlap in time. Here, we provide a general overview of such characteristics and 23 new 40Ar/39Ar eruption ages of glaciovolcanic deposits ranging from 4.3 Ma to 63 ka to constrain the timing, location, and minimum thicknesses and distributions of coincident ice. Subaerial lava fields interspersed with glaciovolcanism record periods of ice-sheet absence in presumably warmer climate conditions. These generally coincide with interglacial marine isotope stages. Many of the volcanoes have a secondary record of posteruption glacial modification, cirques, erratics, and mega-lineations, which document later climate changes up to the present. We used edifice-based terrain analysis to reconstruct changes to local minimum Cordilleran ice-sheet thicknesses, extents, and flow directions at specific locations and times during the late Pliocene and the Pleistocene.

Comments

This published version is made available on Dickinson Scholar with the permission of the publisher. For more information on the published version, visit GeoScienceWorld's Website.

© 2020 The Authors.

Gold Open Access: This chapter is published under the terms of the CC-BY license and is available open access on www.gsapubs.org.

DOI

10.1130/2020.2548(12)

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