HR: 1340h
AN: P33B-1305    [Abstracts]
TI: Steep Sided Domes on Venus: A Re-evaluation of Morphologies and Emplacement Mechanisms
AU: * Gleason, A L
EM: agleason@gi.alaska.edu
AF: University of Alaska, Fairbanks Department of Geology and Geophysics, Reichardt Building Room 308, 900 Yukon Drive P.O. Box 755780, Fairbanks, AK 99775, United States
AU: * Gleason, A L
EM: agleason@gi.alaska.edu
AF: Geophysical Institute, 903 Koyukuk Drive, Fairbanks, AK 99775, United States
AU: Herrick, R
EM: rherrick@gi.alaska.edu
AF: Geophysical Institute, 903 Koyukuk Drive, Fairbanks, AK 99775, United States
AB: Venusian steep sided domes are a volcanic feature noted for their circularity, steep sides, large volumes and relatively flat tops. Several researchers have studied them in order to determine their origins, composition and relation to their surroundings. Previous studies, however, have focused on steep sided domes as a single group and do not often discuss the wide range of morphologies and differences within the dome population. The purpose of this study is to identify features of steep sided domes that can be used in a classification scheme to determine which formational, cooling processes and characteristics are universal to all domes and which are revealing of differing eruptive and cooling histories and mechanisms. A subset of the dome population will be examined for differences and similarities in morphology and for small-scale surface features. Digital elevation models (DEMs) are being generated using the Magellan stereo imagery at 1 km horizontal resolution for all the domes for which stereo coverage is possible. Previous studies have used altimetry data from the Magellan mission, which has ~10 km horizontal resolution. Use of the stereo technique allows for a more accurate estimation of heights and volumes of the domes as well as to better constrain the overall morphology. Initial results show that while many of the existing measurements are in agreement with ours, others are as much as an order of magnitude off. In addition, resolution of smaller scale topography, including depths and extents of surface features such as lineaments, is possible using stereo derived DEMs. Surface lineaments and fractures will be mapped and analyzed to try and determine which lineaments are due to formation or to subsequent cooling processes and how these relate to dome morphology. Preliminary results indicate that while some of the lineament patterns are related to the overall morphology or tectonic history, others seem to indicate multiple eruptive events, possibly indicating polygenetic growth.
DE: 6295 Venus
DE: 8148 Planetary volcanism (5480, 8450)
DE: 8450 Planetary volcanism (5480, 6063, 8148)
SC: Planetary Sciences [P]
MN: 2007 Fall Meeting