saltic weathering fluid evaporation (from L to R). GEOCHEMICAL MODELING OF EVAPORITES ON MARS: INSIGHT FROM MERIDIANI PLANUM. N. J. Tosca, S. M. McLennan, B.C. Clark, J.P. Grotzinger, J.A. Hurowitz, B.L. Jolliff, A.H. Knoll, C. Schröder, S.W. Squyres, and the Athena Science Team. Dept. of Geosciences, State University of New York, Stony Brook, NY 11794, Lockheed Martin Corp., Littleton, CO 80127, Earth, Atmos. & Planetary Sci., Mass. Inst. of Tech., Cambridge, MA 02139, Dept. Earth and Planetary Sciences, Washington University, St. Louis, MO 63130, Botanical Museum, Harvard University, Cambridge, MA 02138, Institut für Anorganische und Analytische Chemie, Johannes GutenbergUniversität, Mainz, Germany, Dept. of Astronomy, Cornell University, Ithaca, NY 14853. (Email: ntosca@ic.sunysb.edu).