Imaging the mantle in southwestern, Utah using geochemistry, and geographic information systems

Basaltic volcanism is common in the transition zone from the Basin and Range to the Colorado Plateau. This study focuses on an 80 km long transect containing seven separate basalt fields spaced less than 20 km apart. The transect extends from eastern Nevada through northwestern Arizona and into southwestern Utah, across the crustal boundary defined as the transition zone; Geochemistry and geographic information systems (GIS) define the geometry and orientation of a mantle boundary trending approximately E-W, almost perpendicular to the crustal boundary. This study suggests that there is no genetic link between the mantle boundary and crustal boundary between the Colorado Plateau and the Basin and Range. This evidence supports the hypothesis that the mantle boundary may be an older more fundamental feature. Geochemical variability within each volcanic field is best explained by fractional crystallization. Field evidence, petrography, geochemistry and new dates support separate evolution of each volcanic field.

Name thesis:degree_name

Master of Science (MS)

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Geoscience

Grantor dc:publisher

University of Nevada, Las Vegas

Year

2000

Author dc:creator

• Downing, Reina Fern

Contributors dc:contributor

• Eugene Smith

Statement dc:rights

• IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/

Language dc:language

English

Identifier

https://oasis.library.unlv.edu/rtds/1144

OAI identifier oai:identifier

oai:oasis.library.unlv.edu:rtds-2143