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<div id="MsgBody" class="MessageBody"><font color="#000000"><font size="2">Large deposits of carbonates had been expected to be wide spread on Mars because of the extensive water in the distant past and because of the CO2 atmosphere. Previously however deposits of carbonates had not been seen from orbit. What was seen from orbit was small amounts of carbonate in the form of dust sprinkled over the planet at perhaps the 2% amount. This was confirmed on the ground by the MER rovers which also saw carbonate only in the form of dust in small amounts. <br />However, the Phoenix lander has found carbonates in significant amounts at its landing site, perhaps in the 6%-8% range. The presence of the carbonate here might be due to the alkalinity of the soil at the Phoenix site compared to acidic soil, as indicated by the presence of sulfates, at the other lander sites. <br />A new report however to be presented at the upcoming "Workshop on Martian Phyllosilicates: Recorders of Aqueous Processes?" will argue that carbonate best fits the spectra in a deposit in the Nili Fossae region on Mars: </font><p> </p><p><font size="2">PHYLLOSILICATES, ZEOLITES, AND CARBONATE NEAR NILI FOSSAE, MARS: EVIDENCE FOR DISTINCT ENVIRONMENTS OF AQUEOUS ALTERATION. B.L. Ehlmann1, J.F. Mustard1, G.A. Swayze2, J.J. Wray3, O.S. Barnouin-Jha4, J.L. Bishop5, D.J. Des Marais6, F. Poulet7, L.H. Roach1, R.E. Milliken8, R.N. Clark2, S.L. Murchie4, and the MRO CRISM Team. 1Dept. of Geological Sciences, Brown University, 2U.S. Geological Survey, Denver, 3Cornell University, 4JHU-Applied Physics Laboratory 5SETI Institute 6NASA Ames 7IAS, Université Paris-Sud, 8JPL-Caltech (****@brown.edu) <br />http://www.lpi.usra.edu/meetings/aqueous2008/pdf/7019.pdf</font></p><p><font size="2">This is to be published in an upcoming article in Science.</font></p><p><font size="2">Other interesting reports from this conference:</font></p><p><font size="2">Program <br />Workshop on Martian Phyllosilicates: Recorders of Aqueous Processes? <br />October 21–23, 2008 <br />http://www.lpi.usra.edu/meetings/aqueous2008/pdf/program.pdf</font></p><p> </p><p><font size="2"> Bob Clark</font><font size="2"> </font></p></font></div> <div class="Discussion_UserSignature"> </div>