UNUSUAL SHOCK METAMORPHISM PRESENT IN A BRECCIA NEAR THE BASE OF THE BLACK DRAGON MEMBER OF THE TRIASSIC MOENKOPI FORMATION, SAN RAFAEL SWELL, UTAH

Rocky Mountain Section - 59th Annual Meeting (7–9 May 2007)
Paper No. 10-5

Presentation Time: 3:45 PM-4:05 PM

UNUSUAL SHOCK METAMORPHISM PRESENT IN A BRECCIA NEAR THE BASE OF THE BLACK DRAGON MEMBER OF THE TRIASSIC MOENKOPI FORMATION, SAN RAFAEL SWELL, UTAH
FANDRICH, Joe W., Department of Environmental and Physical Science, Mesa State College, 2415 Desert Meadows Court, Grand Junction, CO 81505, joefandrich@hotmail.com Fractures in chert, quartz, and other mineral fragments in a breccia present near the base of the Black Dragon Member of the Moenkopi Formation, San Rafael Swell, Utah appear to have been created by a high energy shock wave. Examination of the orientation of the fractures in some of the chert fragments exhibit primarily northwest strikes with steep to vertical dips. In east/west oriented samples several undulating horizontal fractures are observed. Many observed fractures were filled with mud and silt particles at the time of their formation suggesting the minerals in the breccia were suspended in an unconsolidated silt and mud matrix when fractured. There are no shear planes associated with these fractures.
Rocky Mountain Section - 59th Annual Meeting (7–9 May 2007) General Information for this Meeting

Session No. 10 Trace and Indirect Evidence of Terrestrial Bolide Impacts Dixie Center: Entrada A 2:00 PM-4:10 PM, Monday, 7 May 2007 Geological Society of America Abstracts with Programs, Vol. 39, No. 5, p. 12
© Copyright 2007 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.