Phase equilibrium investigations of the Adirondack Class basalts from the Gusev plains, Gusev crater, Mars
Name
86128364-MIT.pdf
Description
Full printable version
Size
2.12 MB
Format
Adobe PDF
Checksum (MD5)
a78fc62f6a5503e259fc956f3b3e70f0
Author(s)
Monders, Anna Gabrielle Bogan
Advisor(s)
Timothy L. Grove.
Date Issued
2006
Publisher
Massachusetts Institute of Technology
Abstract
Phase equilibrium experiments have been performed on a synthetic analog of the Gusev plains basalt composition from the Spirit landing site on Mars, determined by the Alpha Particle X-ray Spectrometer on the Spirit Rover (Gellert et al., 2006; McSween et al., 2006). The near-liquidus phase relations were determined over the pressure range of 0.1 MPa to 1.5 GPa and at temperatures from 1105 °C to 1390 °C in a piston cylinder apparatus and l-atm gas mixing furnace. The composition is multiply saturated with olivine, orthopyroxene, and spinel on the liquidus at 1310 °C and 1.0 GPa, or 85 km depth on Mars, placing an upper limit constraint on the thickness of the Martian lithosphere at the time of eruption. Experiments carried out at 0.1 MPa show Fo77 olivine as the first liquidus silicate mineral, appearing near 1250 °C. Olivine and spinel co-crystallize until pigeonite and plagioclase (An73) join the crystallizing assemblage at 1125 °C. Low pressure crystallization of the Gusev composition does not produce liquids that could be parental magmas to surface types 1 and 2 of the Martian surface, nor do they appear to be related to olivine-phyric shergottites or other SNC meteorites. The iron-rich Gusev basalts appear to have been crystallized from a less depleted mantle source than the magnesian olivine-phyric shergottite Yamoto 980459.
Description
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2006.
Includes bibliographical references (leaves 48-51).
Subjects
Earth, Atmospheric, and Planetary Sciences.
MIT Department
Massachusetts Institute of Technology. Department of Earth, Atmospheric, and Planetary Sciences
Terms of Use
M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.
Persistent DSpace Link