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dc.contributor.advisor Burchfiel, B. C.
dc.creatorLambert, William R.
dc.date.accessioned 2018-12-18T21:16:24Z
dc.date.available 2018-12-18T21:16:24Z
dc.date.issued 1978
dc.identifier.urihttps://hdl.handle.net/1911/104027
dc.description.abstract The Winters Pass thrust plate carries a section of Precambrian basement and its sedimentary cover rocks over Precambrian and lower Paleozoic sedimentary rocks. The thrust plate has undergone two periods of movement: the first to the southeast, and the second to the northeast. The basal 3 to 4 meters of this thrust plate consists of basement rocks that are cataclastically deformed, locally blastomylonitic and contain a well-developed cataclastic foliation and mineral lineation due to feldspar and quartz streaking. In the higher parts of the thrust plate, the cataclastic rocks present in the basement are mylonitic gneisses and mylonites. Relatively undeformed gneisses are present above the mylonites and throughout the thrust plate interspersed with cataclastic rocks. Closely spaced shear fractures are present throughout the gneiss. However, they are not well-developed in the blastomylonites in the lower parts of the thrust or in the upper part where they become progressively less well developed. The shear fractures are also absent in areas of massive quartzo-feldspathic rocks. Microshear fractures, however, are found in all thin sections studied throughout the plate. Stress distribution was determined by using conjugate shear fractures present both in the field and in thin-section. The earliest stress field had with a NWSE subhorizontal orientation and varying in orientation between northeast plunging 55 degrees and southwest plunging 4 degrees. The second stress field had a subhorizontal NE-SW orientation for o oriented in a southeastern direction with plunges varying between 4 and 9 degrees. These two different stress distributions indicate two separate thrusting events. Overturned folds in the area agree with this interpretation and also give direction of movement. These folds indicate the first movement of the Winters Pass thrust plate was to the southeast and the second movement was to the northeast.
dc.format.extent 103 pp
dc.language.iso eng
dc.title Stress distribution in the Winters Pass thrust plate
dc.identifier.digital RICE1653
dc.type.genre Thesis
dc.type.material Text
thesis.degree.department Earth Science
thesis.degree.discipline Natural Sciences
thesis.degree.grantor Rice University
thesis.degree.level Masters
thesis.degree.name Master of Arts
dc.format.digitalOrigin reformatted digital
dc.identifier.callno Thesis Geol. 1978 Lambert
dc.identifier.citation Lambert, William R.. "Stress distribution in the Winters Pass thrust plate." (1978) Master’s Thesis, Rice University. https://hdl.handle.net/1911/104027.


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