A Caltech Library Service

Comment and Reply on "Escape hypothesis for the Stikine block"

McGroder, Michael F. and Umhoefer, Paul J. and Klepacki, D. and Wernicke, B. P. (1989) Comment and Reply on "Escape hypothesis for the Stikine block". Geology, 17 (12). pp. 1162-1163. ISSN 0091-7613. doi:10.1130/0091-7613(1989)017<1161:CAROEH>2.3.CO;2.

Full text is not posted in this repository. Consult Related URLs below.

Use this Persistent URL to link to this item:


When stratigraphic, geochemical, and faunal data of Wrangellia and Wallowa-Seven Devils are viewed objectively, the data suggest—but do not require—that the two crustal blocks developed adjacent to one another. Sarewitz (1983) and Rusmore (1987) noted that the geochemical differences between the arclike Wallowa and Cadwallader volcanic rocks vs. the back-arclike Karmutsen volcanics on Wrangellia may be the result of their tectonic setting relative to the arc axis. We disagree with Mortimer's (1986) correlation of Wallowa volcanics with Stikinia volcanics because the subalkalic volcanic rocks of Wallowa are mainly Ladinian in age and compare poorly with the calc-alkalic augite porphyry of Carnian- Norian age that is typical of Stikine. Newton (1983) reported that Late Triassic molluscan fauna from the Wallowa terrane are most similar to those collected from the Wrangell Mountains. As addressed below, paleomagnetic data do not constrain Wallowa-Wrangellia-Stikine correlations. It appears, therefore, that faunal ties and timing of volcanism indicate that the Wallowa terrane is more similar to Wrangellia than to Stikine, and we incorporate this correlation into our model until direct evidence can support or deny it.

Item Type:Article
Related URLs:
URLURL TypeDescription<1161:CAROEH>2.3.CO;2DOIArticle Article
Wernicke, B. P.0000-0002-7659-8358
Additional Information:© 1989 Geological Society of America.
Issue or Number:12
Record Number:CaltechAUTHORS:20140721-133116492
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:47369
Deposited By: Tony Diaz
Deposited On:21 Jul 2014 20:57
Last Modified:10 Nov 2021 17:38

Repository Staff Only: item control page