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Discovery of Olivine in the Nili Fossae Region of Mars

T.M. Hoefen·R. N. Clark·J. L. Bandfield·M. D. Smith·J.C. Pearl·P. R. Christensen
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Abstract

We have detected a 30,000-square-kilometer area rich in olivine in the Nili Fossae region of Mars. Nili Fossae has been interpreted as a complex of grabens and fractures related to the formation of the Isidis impact basin. We propose that post-impact faulting of this area has exposed subsurface layers rich in olivine. Linear mixture analysis of Thermal Emission Spectrometer spectra shows surface exposures of 30% olivine, where the composition of the olivine ranges from Fo30 to Fo70.

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T.M. Hoefen, R. N. Clark, J. L. Bandfield, M. D. Smith, J.C. Pearl, P. R. Christensen. 2003. Discovery of Olivine in the Nili Fossae Region of Mars. https://doi.org/10.1126/science.1089647

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