Alexandria Digital Research Library

Age, Provenance, and Facies Architecture of an arid-land fluvial system in equatorial Pangaea : The Cloud Chief Formation in western Oklahoma, U.S.A

Author:
Brillo, Vanessa May
Degree Grantor:
University of California, Santa Barbara. Geological Sciences
Degree Supervisor:
Alexander R. Simms
Place of Publication:
[Santa Barbara, Calif.]
Publisher:
University of California, Santa Barbara
Creation Date:
2015
Issued Date:
2015
Topics:
Geology
Keywords:
Oklahoma
Permian
Rivers
Cloud Chief Formation
Genres:
Online resources and Dissertations, Academic
Dissertation:
M.S.--University of California, Santa Barbara, 2015
Description:

The Permian redbeds of the Midcontinent U.S.A. are thought to contain important clues to the climate history of western Pangaea. However, before these units can be used as paleoclimatic archives, better constraints are needed on their age, depositional environment, and provenance. In this study, 43 stratigraphic sections were measured within the Lopingian Cloud Chief Formation of western Oklahoma. The sections were complemented by strontium isotope analysis and detrital zircon geochronology. Nine facies were recognized within the measured sections. These facies include massive gypsum, gypsiferous sandstones, channelized very fine sandstones, thickly-bedded sandstones, siltstones, variegated mudstones, ripple cross-laminated very fine sandstones, interbedded sandstones and mudstones, and silty claystones. These facies are interpreted to represent subenvironments of widespread arid-land fluvial systems flowing into a sabkha. These interpretations fit well with other recent work calling for arid conditions within the midcontinent during the middle Permian. Detrital zircon geochronology points to a dominant sediment source to the east (Ouachita Mountains) with a subordinate source to the west (Ancestral Rocky Mountains in Colorado and New Mexico). Strontium isotope values of the massive gypsum facies provide evidence for marine encroachment during periods of high relative sea level. These isotope values point to an age for the Cloud Chief of 262 +/- 3 Ma to 255 +/- 3 Ma, providing some of the first numerical ages from the redbeds of western Oklahoma.

Physical Description:
1 online resource (91 pages)
Format:
Text
Collection(s):
UCSB electronic theses and dissertations
ARK:
ark:/48907/f3x066kj
ISBN:
9781339472232
Catalog System Number:
990046179540203776
Rights:
Inc.icon only.dark In Copyright
Copyright Holder:
Vanessa May Brillo
File Description
Access: Public access
Brillo_ucsb_0035N_12846.pdf pdf (Portable Document Format)