THE BLACK DRAGON BRECCIA AND THE LONG CANYON MEGABRECCIA, SOUTHEASTERN UTAH: A SHARED PROVENANCE?

Rocky Mountain Section - 57th Annual Meeting (May 23–25, 2005)
Paper No. 1-10

Presentation Time: 11:00 AM-11:15 AM
THE BLACK DRAGON BRECCIA AND THE LONG CANYON MEGABRECCIA, SOUTHEASTERN UTAH: A SHARED PROVENANCE?
FANDRICH, Joe, Mesa State College, Grand Junction, CO, joefandrich@hotmail.com. Unsorted chert breccia deposits situated at the base of the Black Dragon Member of the Triassic Moenkopi Formation in the San Rafael Swell, and a megabreccia associated with extraordinary soft-sediment deformation in the upper 80 – 100 feet of the Hoskinnini Member of the Moenkopi Formation in the White Canyon area of southeastern Utah may share a common history. Chert fragments within the Black Dragon Breccia as well as chert fragments present within the Long Canyon Megabraccia appear to have been scoured from Permian Kaibab Limestone, transported eastward and deposited upon the western Pangaea shoreline. Impact related microspherules have been discovered associated with the Black Dragon Breccia. The Black Dragon Breccia and Hoskinnini are rock correlative and lie unconformably upon Permian age rocks. Field and laboratory observations support the hypothesis that the Black Dragon Breccia and the Long Canyon Megabreccia may represent a bolide impact event horizon resulting from the impact of a comet or asteroid west of Pangaea in the Panthalassa Sea sometime near the PermoTriassic boundary.
Rocky Mountain Section - 57th Annual Meeting (May 23–25, 2005) General Information for this Meeting

Session No. 1 Tectonics, Geophysics, Structural Geology and Bolide Impacts Mesa State College: Saccomanno Lecture Hall 8:00 AM-12:00 PM, Monday, May 23, 2005 Geological Society of America Abstracts with Programs, Vol. 37, No. 6, p. 4
© Copyright 2005 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.