Thermal overprint on blueschists of the Seward Peninsula: The Lepontine in Alaska

Abstract

Research Article| December 01, 1988 Thermal overprint on blueschists of the Seward Peninsula: The Lepontine in Alaska Brian E. Patrick; Brian E. Patrick 1Department of Geology and Geophysics, University of Calgary, Calgary, Alberta T2N 1 N4, Canada Search for other works by this author on: GSW Google Scholar Joshua E. Lieberman Joshua E. Lieberman 2Department of Geological Sciences, AJ-20, University of Washington, Seattle, Washington 98195 Search for other works by this author on: GSW Google Scholar Author and Article Information Brian E. Patrick 1Department of Geology and Geophysics, University of Calgary, Calgary, Alberta T2N 1 N4, Canada Joshua E. Lieberman 2Department of Geological Sciences, AJ-20, University of Washington, Seattle, Washington 98195 Publisher: Geological Society of America First Online: 02 Jun 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 Geological Society of America Geology (1988) 16 (12): 1100–1103. https://doi.org/10.1130/0091-7613(1988)016<1100:TOOBOT>2.3.CO;2 Article history First Online: 02 Jun 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Brian E. Patrick, Joshua E. Lieberman; Thermal overprint on blueschists of the Seward Peninsula: The Lepontine in Alaska. Geology 1988;; 16 (12): 1100–1103. doi: https://doi.org/10.1130/0091-7613(1988)016<1100:TOOBOT>2.3.CO;2 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract On the Seward Peninsula, Alaska, blueschists and greenschists of the Nome Group and amphibolites and granulites of the Kigluaik Group all formed during a single episode of continent-arc collision. High-pressure/low-temperature mineral assemblages that initially developed in a structurally coherent package of miogeoclinal rocks were then variably overprinted during later uplift by lower P/higher T Barrovian facies series assemblages. Derived pressure-temperature-time (P-T-t) paths illustrate the early passage of both the Nome and Kigluaik Groups through high-pressure (> 12 kbar) conditions, subsequent nearly isothermal decompression of Nome Group blue- schists, and divergence during decompression of nested P-T paths to amphibolite and granulite conditions in the underlying Kigluaik Group. Similar field occurrences are described from the Lepontine Alps and the Greek island of Naxos. Standard geobarometric techniques applied to medium-grade Kigluaik Group rocks do not record the earliest burial phase and therefore underestimate peak pressures by ∼8 kbar. This content is PDF only. Please click on the PDF icon to access. First Page Preview Close Modal You do not have access to this content, please speak to your institutional administrator if you feel you should have access.