HR: 0800h
AN: P41B-0933    [Abstracts]
TI: Physical Characteristics and Processes of 100-m-scale raised-rim depressions (RRD's) on Earth: application to Mars
AU: * Burr, D M
EM: dburr@seti.org
AF: SETI Institute, 515 N Whisman Rd., Mountain View, CA 94043 United States
AU: Bruno, B
EM: barb@hawaii.edu
AF: HIGP, University of Hawai'i, 2525 Correa Rd., Honolulu, HI 96822 United States
AU: Jaeger, W L
EM: wjaeger@usgs.gov
AF: U.S. Geological Survey, Astrogeology Team, 2255 N Gemini Dr., Flagstaff, AZ 86001 United States
AU: Lanagan, P D
EM: planagan@lpl.arizona.edu
AF: Lunar and Planetary Lab, University of Arizona, 1629 E University Blvd., Tucson, AZ 85721 United States
AU: Miyamoto, H
EM: miyamoto@geosys.t.u-tokyo.ac.jp
AF: Department of Geosystem Engineering, University of Tokyo, Tokyo, 113-8656 Japan
AU: Soare, R
EM: rsoare@colba.net
AF: Department of Geography, Planning and Environment, Concordia University, 1455 De Maisoneuve w., Montreal, H3G 1M8 Canada
AU: Wan Bun Tseung, J
EM: jmwan@telus.net
AF: Department of Geography, University of Calgary, 2500 University Dr. NW, Calgary, T2N 1N4 Canada
AB: 100-m-scale raised-rim depressions (RRD's) of various origins are found on both Earth and Mars. We define RRD's morphologically, as circular, elongate, or irregularly shaped forms having raised rims encircling lower elevation terrain. Terrestrial RRD's include phreatomagmatic cones, basaltic ring structures, collapsing or collapsed pingos, rimmed kettle holes, and mud volcanoes. Terrestrial experience commonly guides extra-terrestrial investigations, so these terrestrial types of RRD's are also the types that have been commonly hypothesized for RRD's on Mars, although other origins (e.g., secondary impacts onto deflating surfaces) are also likely on Mars. Identifying the origins of Martian RRD's is useful because different types of RRD's imply different geological processes (and therefore have different astrobiological connotations). Being of a similar shape and size in plan view, different types of RRD's are often difficult to classify remotely. However, each of these types of RRD's has specific geomorphic characteristics that can be remotely assessed. Based on terrestrial studies, we present guidelines of a scale applicable to new current and near-future spacecraft data to aid in identifying various types of RRD's on Mars. This presentation will entail discussion of selected types of RRD's, including their geneses, morphologic characteristics, distributions, and common geological associations. The RRD's are grouped according to primary origin, ie., volcanic, sedimentologic, and other. In summary, we present some guidelines for classifying RRD's on Mars.
DE: 5464 Remote sensing
DE: 5470 Surface materials and properties
SC: Planetary Sciences [P]
MN: Fall Meeting 2005