Repository logo
 

Sequence stratigraphic distribution of coal-bearing rocks from the Mesaverde Group in the easternmost Atlantic Rim of the Washakie Basin, Wyoming

Simple item page
dc.contributor.authorDereume, Jeffrey Michael, author
dc.contributor.authorEgenhoff, Sven O., advisor
dc.contributor.authorHarry, Dennis L., committee member
dc.contributor.authorvon Fischer, Joseph C., committee member
dc.date.accessioned2007-01-03T05:40:33Z
dc.date.available2007-01-03T05:40:33Z
dc.date.issued2010
dc.description.abstractCoals occur in various levels of the siliciclastic Campanian upper Mesaverde Group in the Atlantic Rim area, Washakie Basin, south central Wyoming. This unit consists of continental, delta, and offshore facies showing several orders of internal cyclic architecture. At least five large-scale cycles form the upper part of the Mesaverde Group, internally arranged in stacks of up to five medium-scale cycles that are in turn subdivided into a maximum of five small-scale cycles. These cycles reflect million-year to Milankovitch-type sea-level fluctuations causing trans- and regression of varying magnitude, within an overall transgressive regime. Coals developed preferentially in paralic and lower coastal plain environments in the Atlantic Rim in relative proximity to a nearby delta. The position closest to the shoreline was occupied by coal-rich mudstones reflecting siliciclastic input from the delta and the sea during floods. Both coals and coal-rich siliciclastic mudstones occur during all stages of a sea-level curve. While previous models suggested a preferential accumulation of coals during early transgressions, a peak in coal frequency characterizes early regressive sediments within the Mesaverde Group in the Atlantic Rim. This is believed to be the result of a heightened water table during early regressions promoting anoxic swamp and marsh environments, and frequent flooding of floodplains forming an ideal setting for accumulation of organic matter. The lateral continuity of Mesaverde coals is also positively influenced by development within paralic settings. Many of the most correlative coal seams in the Atlantic Rim occur within close stratigraphic proximity and/or lateral to marine deposits. Integrating a sequence stratigraphic framework into the upper Mesaverde Group significantly enhances prediction patterns of coaly rocks by constraining their stratigraphic and lateral distributions. Clay- and silt-bearing organic-rich mudstones mark the transition from continental to marine facies, while pure coals only occur at a distance from the shoreline. The overall transgressive nature of the upper part of the Mesaverde Group reveals a highly diachronous facies distribution within the Washakie Basin. A significantly thicker coal-bearing interval characterizes the southern part, while successions further north show abundant mudstones, representing an overall earlier transition to marine conditions.
dc.format.mediumborn digital
dc.format.mediummasters theses
dc.identifierDereume_colostate_0053N_10225.pdf
dc.identifierETDF2010100006GEOS
dc.identifier.urihttp://hdl.handle.net/10217/48847
dc.languageEnglish
dc.language.isoeng
dc.publisherColorado State University. Libraries
dc.relation.ispartof2000-2019
dc.rightsCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.
dc.subjectcoal
dc.subjectcorrelation
dc.subjectMesaverde
dc.subjectsedimentology
dc.subjectsequence
dc.subjectstratigraphy
dc.titleSequence stratigraphic distribution of coal-bearing rocks from the Mesaverde Group in the easternmost Atlantic Rim of the Washakie Basin, Wyoming
dc.typeText
dcterms.rights.dplaThis Item is protected by copyright and/or related rights (https://rightsstatements.org/vocab/InC/1.0/). You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).
thesis.degree.disciplineGeosciences
thesis.degree.grantorColorado State University
thesis.degree.levelMasters
thesis.degree.nameMaster of Science (M.S.)

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
Dereume_colostate_0053N_10225.pdf
Size:
11.69 MB
Format:
Adobe Portable Document Format
Description:
Download

Collections

2000-2019
Theses and Dissertations