Table 3. Characteristics of Major Classes of Aqueous Mineral-Bearing Deposits Known Through Late 2008 Short Name Aqueous Minerals Present Morphology Distribution Type Area With CRISM/HiRISE Image IDs Layered phyllosilicate Al smectite, kaolinite group, Fe/Mg smectite, hydrated silica, Fe oxides 10s-m thick blanket of Al phyllosilicate and hydrated silica overlying Fe/Mg smectite, commonly polygonally fractured; exposed where protective caprock has been removed Mawrth Valles and surrounding regions, Nili Fossae; small exposures elsewhere Plains surrounding Mawrth Valles, 24.7N, 339.1E, HRL000043EC, PSP_005819_2050 Phyllosilicates in intracrater fans Fe/Mg smectites from drainage basins Fan-shaped deposit where channel debouches into crater; phyllosilicate typically in lower, tabular strata Holden, Eberswalde, Jezero, Terby craters Jezero Crater, 18.5N, 77.4E, HRL000040FF, PSP_002387_1985 Plains sediments Chlorides and Fe/Mg smectites Eroded remnants of phyllosilicate-rich deposits in topographic low, sometimes forming piedmont; may be embayed by chloride Scattered throughout highland plains in crater floors and intercrater plains Terra Sirenum, 32.7S, 205.5E, HRL0000860C, PSP_005811_1470 Deep phyllosilicates Various phyllosilicates, dominated by prehnite, chlorite, Fe/Mg smectite Massive or bouldery to layered outcrops in crater walls and central peaks, massifs, and chasma walls and escarpments Craters walls and central peaks in highland plains, walls of Valles Marineris Wall of Valles Marineris, 14.0S, 304.4E, FRT00009804, PSP_006928_1660 Carbonate deposits Magnesium carbonate, possibly other hydrated phases Thin bed overlying or grading into olivine-rich rock; superposed by resistant caprock Thin outcrops surrounding Isidis basin Nili Fossae, 21.9N, 78.4E, FRT0000B072, PSP_002176_2025 Intracrater clay-sulfate deposits Kaolinite, hydrated sulfates including alunite and maybe jarosite Interbedded phyllosilicate and sulfate layers on crater walls forming "bathtub ring" pattern Craters in Terra Sirenum Columbus crater, 28.5S, 194.0E, FRT00007D87, PSP_005429_1510 Meridiani-type layered deposits Hydrated sulfates, jarosite, hematite Undeformed layers superposed on cratered terrain; monohydrated or polyhydrated sulfates in various layers; extensive eolian erosion; some strata rich in hematite Terra Meridiani and Aram Chaos Terra Meridiani, 2.3N, 359.7E, FRT00004616, PSP_002680_1825 Valles-type layered deposits Hydrated sulfates, Fe oxides and sulfates Thick stack of layers infilling chasmata; mostly horizontal bedding deformed by folding and faulting; monohydrated or polyhydrated sulfates in discrete layers; extensive eolian erosion; some strata rich in Fe oxide Valles Marineris including Candor, Melas, Juventae, Tithonium, and Eos Chasmata Candor Chasma, 5.8S, 286.1E, FRT00009CB6, PSP_007166_1740 Siliceous layered deposits Hydrated silica including opal, also jarosite Thin, light-toned, layered deposits; extensive eolian stripping, inverted stream channels Plains surrounding Valles Marineris Plains west of Juventae Chasma, 4.6S, 296.4E, FRT00005814, PSP_005429_1510 Gypsum plains Gypsum, probably other hydrated minerals Dark, sandy material in part of polar basal unit reworked into dunes Dark sediments in north polar erg and north polar layered deposits Olympia Undae, 80.0N, 240.7E, FRT0000285F, PSP_001432_2610