Pedogenic gypsum of southern New Mexico: Genesis, morphology, and stable isotopic signature

Recent work in Canada and Iran (Dowuona et al., 1992 and Khademi et al., 1997a; 1997b) suggested a correlation exists between the delta18 O and deltaD ratios of the hydration water of pedogenic gypsum and the delta18O/deltaD ratios of meteoric water. However, a pedogenic origin for the sampled gypsum was not clearly supported and the results from this procedure were not compared to other paleoclimatic indicators. Therefore, the goals of this study were, (1) evaluate the genesis and soil morphology of pedogenic gypsum in and to semi-arid regions and (2) determine the applicability of pedogenic gypsum as a paleoclimatic indicator; Six profiles containing soils of late Pleistocene through Holocene age in the Tularosa and Jornada basins of Southern New Mexico were described and sampled for isotopic analysis. Gypsum soil morphology was expanded to include a new "snowball" morphology, as well as Stage I filaments and Stage II nodules, a classification scheme formerly only applied to carbonate morphology. A pedogenic origin for gypsum crystals found throughout the six profiles was determined using a scanning electron microscope. (Abstract shortened by UMI.).

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

• Van Hoesen, John Grant

Contributors dc:contributor

• Brenda J. Buck

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/1186

OAI identifier oai:identifier

oai:oasis.library.unlv.edu:rtds-2185