The origin and evolution of the deep lithosphere beneath continental arcs: constraints from lower crustal and mantle xenoliths from the Sierra Nevada, California
| dc.contributor.advisor | Lee, Cin-Ty A. | en_US |
| dc.contributor.committeeMember | Dasgupta, Rajdeep | en_US |
| dc.contributor.committeeMember | Whitmire, Kenton H. | en_US |
| dc.contributor.committeeMember | Gonnermann, Helge M. | en_US |
| dc.creator | Chin, Emily | en_US |
| dc.date.accessioned | 2014-08-07T19:57:13Z | en_US |
| dc.date.available | 2014-08-07T19:57:13Z | en_US |
| dc.date.created | 2013-12 | en_US |
| dc.date.issued | 2013-11-18 | en_US |
| dc.date.submitted | December 2013 | en_US |
| dc.date.updated | 2014-08-07T19:57:14Z | en_US |
| dc.description.abstract | Lower crustal and upper mantle xenoliths from the Sierra Nevada continental arc in California, USA reveal a complex P-T-X-t (pressure-temperature-composition-time) evolution of the deep lithosphere. Metasedimentary xenoliths, despite high quartz contents, preserve granulite-facies equilibration conditions, necessitating transport from the surface into the lower crust. U-Pb and Hf isotope data on detrital zircon in the metasediments support continental underthrusting coeval with the peak of arc magmatism. Mantle xenoliths, represented by spinel and garnet-bearing spinel peridotites, indicate that shallow (spinel-facies), high-degree melt residues underwent thickening, cooling, and metamorphism into refertilized garnet peridotites that equilibrated below 800 °C and ca. 3 GPa. The source of refertilizing melts appears to be the mantle wedge itself, rather than the subducting slab based on mass-balance models and oxygen isotopes. Textural disequilibria, particularly Al-depletion haloes between orthopyroxene and exsolved garnet in peridotites, are diagnostic features related to cooling and increasing pressure. Diffusion modeling indicate that such disequilibria formed within 6 to 8 Ma. Coupled Lu-Hf and Sm-Nd age data on garnet pyroxenites show a significant lag between closure of the two chronometers in a lower crustal pyroxenite, but negligible difference in the deepest websterites. As a whole, the Sierran xenolith data provide insights into the origin and evolution of a mature continental arc, particularly highlighting the importance of thickening in both the crust and mantle lithosphere. | en_US |
| dc.format.mimetype | application/pdf | en_US |
| dc.identifier.citation | Chin, Emily. "The origin and evolution of the deep lithosphere beneath continental arcs: constraints from lower crustal and mantle xenoliths from the Sierra Nevada, California." (2013) Diss., Rice University. <a href="https://hdl.handle.net/1911/76480">https://hdl.handle.net/1911/76480</a>. | en_US |
| dc.identifier.uri | https://hdl.handle.net/1911/76480 | en_US |
| dc.language.iso | eng | en_US |
| dc.rights | Copyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder. | en_US |
| dc.subject | Mantle petrology | en_US |
| dc.subject | Xenoliths | en_US |
| dc.subject | Sierra Nevada | en_US |
| dc.subject | Geology | en_US |
| dc.title | The origin and evolution of the deep lithosphere beneath continental arcs: constraints from lower crustal and mantle xenoliths from the Sierra Nevada, California | en_US |
| dc.type | Thesis | en_US |
| dc.type.material | Text | en_US |
| thesis.degree.department | Earth Science | en_US |
| thesis.degree.discipline | Natural Sciences | en_US |
| thesis.degree.grantor | Rice University | en_US |
| thesis.degree.level | Doctoral | en_US |
| thesis.degree.name | Doctor of Philosophy | en_US |