Palynological and tephra correlations among deep wells in the modern Great Salt Lake, Utah, USA : implications for a neogene through pleistocene climatic reconstruction

Persistent Link:
http://hdl.handle.net/10150/191347
Title:
Palynological and tephra correlations among deep wells in the modern Great Salt Lake, Utah, USA : implications for a neogene through pleistocene climatic reconstruction
Author:
Moutoux, Thomas E.
Issue Date:
1995
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Palynological and tephra information provides the foundation for correlation of five deep wells from the Great Salt Lake. Pollen correlations are primarily resolved using pollen percentage diagrams. Analysis of the individual tephra units allow correlation of tephras based on chemical similarities. Known regional tephras recognized in one or more of the wells are the Lava Creek B ash bed, the Bishop ash bed, the Huckleberry Ridge ash bed, the Santee ash bed and the Walcott ash bed. Absolute ages associated with these ash beds and three other units subsequently allow for the calculation of long term sediment accumulation rates at each well location. Sediment accumulation rates, averaged over the last 4 to 5 million years of record, range between 0.18 mm/yr and 0.43 mm/yr, with fairly constant rates within each well. The two longest records, which represent an approximated 16 million years, provide average sedimentation rates over this entire period of 0.23 mm/yr and 0.13 mm/yr. Neogene through Pleistocene paleoclimatic conditions are estimated using pollen percentages based on the pollen counts from all five wells. Quantitative climatic interpretations based on the palynology suggest close to modern, but slightly warmer and drier conditions from ca. 7 million years ago (Ma) to ca. 3.5 Ma. The period lasting from ca. 3.5 Ma to ca. 0.7 Ma was characterized by a clearly hotter and more arid climate compared to today; though a short cool period may have occurred between 2.7 and 2.9 Ma. Conditions over the last 0.7 Ma were generally cooler and moister than the previous period, and at times may have been significantly cooler and moister than the modern climate. A qualitative estimate of precipitation conditions based on Pinus percentages suggests higher than modern mean annual precipitation in the mid-Miocene, with an overall decrease through the Pliocene.
Type:
Thesis-Reproduction (electronic); text
LCSH Subjects:
Hydrology.; Palynology -- Utah.; Wells -- Utah -- Great Salt Lake Watershed.; Groundwater -- Utah -- Great Salt Lake Watershed.
Degree Name:
M.S.
Degree Level:
masters
Degree Program:
Geosciences; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
Davis, Owen

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titlePalynological and tephra correlations among deep wells in the modern Great Salt Lake, Utah, USA : implications for a neogene through pleistocene climatic reconstructionen_US
dc.creatorMoutoux, Thomas E.en_US
dc.contributor.authorMoutoux, Thomas E.en_US
dc.date.issued1995en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractPalynological and tephra information provides the foundation for correlation of five deep wells from the Great Salt Lake. Pollen correlations are primarily resolved using pollen percentage diagrams. Analysis of the individual tephra units allow correlation of tephras based on chemical similarities. Known regional tephras recognized in one or more of the wells are the Lava Creek B ash bed, the Bishop ash bed, the Huckleberry Ridge ash bed, the Santee ash bed and the Walcott ash bed. Absolute ages associated with these ash beds and three other units subsequently allow for the calculation of long term sediment accumulation rates at each well location. Sediment accumulation rates, averaged over the last 4 to 5 million years of record, range between 0.18 mm/yr and 0.43 mm/yr, with fairly constant rates within each well. The two longest records, which represent an approximated 16 million years, provide average sedimentation rates over this entire period of 0.23 mm/yr and 0.13 mm/yr. Neogene through Pleistocene paleoclimatic conditions are estimated using pollen percentages based on the pollen counts from all five wells. Quantitative climatic interpretations based on the palynology suggest close to modern, but slightly warmer and drier conditions from ca. 7 million years ago (Ma) to ca. 3.5 Ma. The period lasting from ca. 3.5 Ma to ca. 0.7 Ma was characterized by a clearly hotter and more arid climate compared to today; though a short cool period may have occurred between 2.7 and 2.9 Ma. Conditions over the last 0.7 Ma were generally cooler and moister than the previous period, and at times may have been significantly cooler and moister than the modern climate. A qualitative estimate of precipitation conditions based on Pinus percentages suggests higher than modern mean annual precipitation in the mid-Miocene, with an overall decrease through the Pliocene.en_US
dc.description.notehydrology collectionen_US
dc.typeThesis-Reproduction (electronic)en_US
dc.typetexten_US
dc.subject.lcshHydrology.en_US
dc.subject.lcshPalynology -- Utah.en_US
dc.subject.lcshWells -- Utah -- Great Salt Lake Watershed.en_US
dc.subject.lcshGroundwater -- Utah -- Great Salt Lake Watershed.en_US
thesis.degree.nameM.S.en_US
thesis.degree.levelmastersen_US
thesis.degree.disciplineGeosciencesen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairDavis, Owenen_US
dc.contributor.committeememberCohen, Andrewen_US
dc.contributor.committeememberBull, Williamen_US
dc.identifier.oclc213483174en_US
All Items in UA Campus Repository are protected by copyright, with all rights reserved, unless otherwise indicated.