HR: 1340h
AN: P13A-1036    [Abstracts]
TI: Topographic Roughness of Hawaiian Volcanic Terrains: Analysis of Multiple Datasets Indicates Length Scales are Critical
AU: * Morris, A R
EM: aisham@hawaii.edu
AF: SOEST/HIGP, University of Hawaii, 1680 East-West Road POST 504, Honolulu, HI 96822, United States
AU: Anderson, F S
AF: SOEST/HIGP, University of Hawaii, 1680 East-West Road POST 504, Honolulu, HI 96822, United States
AU: Mouginis-Mark, P
AF: SOEST/HIGP, University of Hawaii, 1680 East-West Road POST 504, Honolulu, HI 96822, United States
AU: Haldemann, A
AF: JPL, Caltech, Pasadena, CA 91109, United States
AU: Brooks, B
AF: SOEST/HIGP, University of Hawaii, 1680 East-West Road POST 504, Honolulu, HI 96822, United States
AU: Foster, J
AF: SOEST/HIGP, University of Hawaii, 1680 East-West Road POST 504, Honolulu, HI 96822, United States
AB: The roughness of a natural surface is often defined by the topography of the surface at scales of a few tens of meters or less. To ensure the safety of rovers and scientific instruments on Mars, these scales are of critical importance during landing site selection and rover traverse operations. Published work on terrestrial and Martian topography datasets has demonstrated that statistical values such as the Hurst exponent can be used in conjunction with related statistical measures such as RMS slope or deviation to quantify the relationship between scale-dependent roughness values and the morphology of a surface. In our detailed studies of the statistical behavior of meter-scale surface roughness on Earth, we determine that the length scales used to calculate the surface roughness affect the resulting roughness statistics and must be taken into account when analyzing planetary surface roughness. Extensive airborne Light Detection and Ranging (a-LiDAR) coverage of the summit of Kilauea volcano on the Big Island of Hawaii (1 m DEM) provides an opportunity for simulating higher resolution Martian topography data such as will be obtained from photoclinometry and stereo imaging using the HiRISE camera on MRO. In addition to the a-LiDAR data, we use high-resolution topography (2 cm DEM) generated from a tripod-mounted scanning LiDAR system (t-LiDAR). Previous authors have described techniques for calculating roughness statistics in one dimension using topographic profiles. We adapt the 1D method for use with 2D topographic datasets to generate maps of the Hurst exponent of Martian analog flows in Hawaii. Results from the surface roughness analysis suggest that the calculated RMS deviation or slope and Hurst exponent exhibit systematic variations as the length of a profile segment (in 1D studies) or size of the cell (in 2D studies) changes. These new results, combined with previously described data, indicate that the length scales used to calculate roughness statistics must be accounted for when describing the statistical behavior of a planetary surface.
DE: 5400 PLANETARY SCIENCES: SOLID SURFACE PLANETS
DE: 5480 Volcanism (6063, 8148, 8450)
DE: 5494 Instruments and techniques
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting