Figure 1. Geologic maps of sections of eastern (left) and southwestern (right) Margaritifer Terra, Mars1-2, at a scale of 1:500,0001. Maps shows a variety of geomorphic units including one of the highest densities of preserved valley network drainage systems on the planet. Maps were published in 20091 and 20132 (left and right, respectively
Geologic mapping is an integral part of exploration and understanding a planetary landscape, because it shows the relationships between geologic units and helps delineate the history of a surface. New orbiting spacecraft are obtaining data with progressively higher resolution, and as a consequence maps constantly need to be updated and improved. Moreover, as researchers' various needs and areas of focus change, maps of different areas and scales are required.
Dr. Grant and colleagues are currently mapping the geologic history and landscape evolution of portions of Margaritifer Terra at a scale of 1:500K1-3 (Figure 2). The map areas in the west are characterized by the large, multi-ring Ladon and Holden impact basins, channels comprising the Uzboi-Ladon-Morava outflow system, highland intercrater plains, late valley network activity, and a range of structural geology such as minor compressional and extensional faults. To the east, the map areas are dominated by Samara, Parana, and Loire Valles, some of the best integrated and largest valley network systems on Mars This region is of particular interest because two of the four final candidate landing sites that were considered for the Mars Science Laboratory (MSL) mission, Holden and Eberswalde craters, are located within the mapping areas.
Figure 2. Topography and morphology in Margaritifer Terra with major features labeled; outlines show quadrangles mapped and being mapped by Grant and others2
1. Grant, J.A., Wilson, S.A., Fortezzo, C.M., and Clark, D.A., 2009, Geologic map of MTM-20012 and -25012 quadrangles, Margaritifer Terra region of Mars: U.S. Geological Survey Scientific Investigations Map 3041, Version 1.0, 1:1,000,000, 1 sheet and pamphlet
2. Irwin, R. P., III, and J. A. Grant (2013), Geologic Map of MTM –15027, –20027, –25027, and –25032 Quadrangles, Margaritifer Terra Region of Mars, U.S. Geol. Surv., Scientific Investigations Map 3209 (in press).
3. Wilson, S. A., and Grant, J. A. (2013), the Hale impact event and associated modification of southern Margaritifer Terra: Planetary Geologic Mappers Meeting Abstracts, June, 19-21, Washington, DC.