42nd Lunar and Planetary Science Conference (2011) 2507.pdf IGNEOUS COMPOSITIONS IN ARES VALLIS: TIMING AND IMPORTANCE OF VOLCANICS AND FLUVIAL PROCESSES AT THE NOACHIAN-HESPERIAN BOUNDARY. J. H. Wilson1 and J. F. Mustard1, 1Department of Geological Sciences, Brown University, Providence, RI 02912 (
[email protected]) Introduction: Ares Vallis is one of many outflow mented as described in [22]. Both the L and S detector channels on Mars generally thought to have formed by data were used. We will be using the much improved the catastrophic outflow of subsurface water e.g. [1, 2, TRR3 data formation as they becom available but this 3]. Yet, the presence of diagnostic signatures of igne- research is focused on the starndard TRR2 data. Spec- ous compositions indicates a complex history. Olivine tra were extracted from regions of interest on the basis is one of the more readily detected igneous mineral of spectral parameter maps [23] using a 5 X 5 pixel signatures and has been detected globally with various average. Residual artifacts after calibration and atmos- instruments including TES, e.g. [4, 5, 6, 7, 8], pheric removal are suppressed by ratioing the spectra THEMIS, e.g. [4, 8, 9], OMEGA, e.g. [10, 11, 12], and to a spectrally neutral region from the same column by the MER rovers in situ, e.g. [13, 14, 15]. Deposits because of the nature of 2-D detectors. with igneous signatures in Ares Vallis can be detected CTX and HiRISE observations, P07_003762_1861 with the high resolution Compact Reconnaissance Im- and ESP_013216_1870 and PSP_008166_1885, re- aging Spectrometer for Mars (CRISM) [16] and their spectively, were used to document morphologies.