Type
Text
Type
Dissertation
Date
2009-08-01
Keywords
Mineral physics | Earth -- Mantle
Language
en_US
Source
This work is sponsored by the Stony Brook University Graduate School in compliance with the requirements for completion of degree.
Identifier
http://hdl.handle.net/11401/71068
Publisher
The Graduate School, Stony Brook University: Stony Brook, NY.
Format
application/pdf
Abstract
We constrain velocity structures and composition models in the Earth’s upper mantle through joint modeling of seismic and mineral physics data, and the composition of Mars through joint modeling of mineral physics data and the observations of moment of inertia. For Earth, we constrain shear (SH) and compressional (P) wave velocity structures in the upper mantle beneath southern Africa, using triplicated phases recorded in the epicentral distance range of 11 o - 28 o for one shallow earthquake. Both SH and P wave data suggest presence of a low velocity zone beneath a high-velocity lithospheric lid. Seismic observations also suggest that the P/S ratio is larger (1.88) in the transition zone than in the lithospheric lid (1.70). We also constrain SH wave velocity structures near the 660-km discontinuity beneath South America and northeast Asia, using iv triplicated phases near the discontinuity recorded in the epicentral distance range of 10 o - 35 o for three deep earthquakes. SH velocity structures near the 660-km discontinuity are found to be different in the two regions. We then explore thermal and compositional models appropriate for explaining the inferred seismic structures in the sampling regions, based on mineral physics modeling. For Mars, we construct density models of the interior of Mars for a series of mantle compositions, core compositions and temperature profiles, and calculate the moment of inertia factors. With the constraints of total mass, possible core radius and observed moment of inertia factor, we find that Fe content in the martian mantle is between 10.5% and 14.3%; Al content in the martian mantle is less than 4%; and S content in the martian core is between 4.6% and 13.3%. We further discuss the implications of these compositional models to the understanding of formation and evolution of Mars. We also adopt the second-order internal theory of equilibrium of a self-gravitating and rotating planet to calculate the hydrostatic figure and flattening factor of Mars.
Recommended Citation
Wang, Yi, "Constraining Composition of Earth Upper Mantle and Mars From Seismic, Mineral Physics and Other Geophysical Data" (2009). Stony Brook Theses and Dissertations Collection, 2006-2020 (closed to submissions). 275.
https://commons.library.stonybrook.edu/stony-brook-theses-and-dissertations-collection/275