Sponsored by National Aeronautics and Space Administration Lunar and Planetary Institute NASA Johnson Space Center LPJ Program to Technical Sessions THIRTY-FIRST LUNAR AND PLANETARY SCIENCE CONFERENCE March 13-17, 2000 Houston, Texas Sponsored by National Aeronautics and Space Administration Lunar and Planetary Institute NASA Johnson Space Center Program Committee Carl Agee, Co-Chair, NASA Johnson Space Center David Black, Co-Chair, Lunar and Planetary Institute Cone! Alexander, Carnegie Institution of Washington Carlton Allen, Lockheed Martin Nadine Barlow, University of Central Florida Harold Connolly, Jr., California Institute ofTechnology Christine Floss, Washington University Lisa Gaddis, U.S. Geological Survey Jeffrey Gillis, Washington University Tracy Gregg, State University of New York-Buffalo Greg Hoppa, University ofArizona Friedrich Horz, NASA Johnson Space Center Noam Izenberg, Johns Hopkins University Michael Kelley, NASA Johnson Space Center Walter Kiefer, Lunar and Planetary Institute Dante Lauretta, Arizona State University Renu Malhotra, Lunar and Planetary Institute Patrick McGovern, Lunar and Planetary Institute Clive Neal, University of Notre Dame Frans Rietrneijer, University of New Mexico Rob Rye, California Institute of Technology Allan Treiman, Lunar and Planetary Institute Thomas Watters, Smithsonian Institution Frances Westall, NASA Johnson Space Center LP I ROOM C 145 FIRST FLOOR Robert R. Gilruth Recreation Facility Building 207 ROOM B 104 148 SECOND FLOOR Robert R. Gilruth Recreation Facility Building 207 CONFERENCE INFORMATION Registration-LPI Open House A combination Registration/Open House will be held Sunday, March 12, 2000, from 5:00 p.m. until 8:00 p.m. at the Lunar and Planetary Institute. Registration will continue in the Gilruth Center, Monday through Thursday, 8:00 a.m. to 5:00 p.m. A shuttle bus will be available to transport participants between the LPI and local hotels Sunday evening from 4:45 p.m. to 8:30p.m. Message Center A message center will be established in the registration area in the Gilruth Center during the oral sessions. People who need to contact attendees during the conference may call 281-483-0321. The message center will be open Monday through Thursday from 8:00 a.m. to 5:00p.m. and Friday from 8:00 a.m. until noon. A fax machine will be located at the staff desk for incoming messages only. Faxes should be sent to 281-483-8722. Telephone messages and faxes will be posted on a bulletin board near the registration desk. Shuttle Bus Service A shuttle bus service between JSC, LPI, University of Houston-Clear Lake, and various hotels will operate daily. A detailed schedule of the shuttle routes is in your registration packet and is available at the registration desk. Badges During the week of the conference, your conference badge will allow access to JSC at all gates, the Gilruth Center, and the JSC cafeterias in Buildings 3 and 11. Please be aware that this badge does not allow access to those areas or buildings not open to the general public except those specifically outlined above. Space Center Houston Space Center Houston is open from 10:00 a.m. until5:00 p.m. daily. Major attractions are the Mission Status Center, Starship Gallery, tour of JSC, Space Shuttle Mock-Up, Space Center Theater, Manned Maneuvering Unit, and Space Center Plaza. Restaurants and gift shops are available. The ticket prices are $13.95 for adults and $9.95 for children ages 4-11 (children 3 and under are free). For further information, call281-244-2105. GUIDE TO TECHNICAL SESSIONS AND ACTIVITIES Monday Morning, 8:30 a.m. Room A Martian Meteorites I Room B Chemistry and Physics of the Early Solar System Room C Mars: Channels, Lakes, and Mud Oceans Room D Impact I: Theory and Experiment Session dedicated to the memory of Donald Gault Monday Afternoon, 1:00 p.m. Room C PLENARY SESSION Presentations to the 1999 GSA Stephen E. Dwornik U.S. Citizen Student Paper Award Winners followed by Harold Masursky Lecture Monday Afternoon, 2:30 p.m. Room A Martian Meteorites II 4:00 p.m. Iron Meteorites Room B Galileo at Io Roome Mars Geophysics RoomD Planetary Interior Processes Tuesday Morning, 8:30 a.m. Room A New Views of the Moon: Thermal Evolution and the Nature of the Lunar Interior I Room B Mars Surface: Up Close Session dedicated to the memory of Henry]. Moore Room C SPECIAL SESSION- NEAR at Eros! First Results RoomD Achondrite Potpourri Tuesday Afternoon, 1:30 p.m. Room A New Views of the Moon: Thermal Evolution and the Nature of the Lunar Interior II RoomE Asteroids and Comets Roome Mars: Oceans, Ice, and Polar Regions RoomD Impact II: Terrestrial Impacts Tuesday Evening, 7:00-9:30 p.m. UHCL Poster Session I Missions: Mars CAis, Condensation, and Even Mars Has Its Faults Evaporation Mars Mapping Martian Meteorites Blue Mars "NEAR Relations" Lunar Remote Sensing: Diggin', Outer Planet Satellites Minin', and Forty-Ninin' Mercury New Views of the Moon: Thermal Impact Theory and Experiment Evolution and the Nature of Terrestrial Impact Craters the Lunar Interior III Planetary Interior Processes Achondrite Potpourri Missions and Experiments Shock Processes in Meteorites Instrumental Techniques Iron Meteorites Space Science Education Wednesday Morning, 8:30 a.m. Room A Refractory Inclusions Room B Gardening on the Moon: Regolith Processes and Characterization Room C Mars: Troughs, Tectonics, and Teslas Room D Stardust: Collected, Remote, and Captured Wednesday Afternoon, 1:30 p.m. Room A Meteorite Chronology and Isotope Systematics Room B Lunar Composition: Remote Yet Intimate Views 3:30 p.m. Dating the Moon: Impact Effects and Petrogenetic Implications Room C Mars: Lumps, Bumps, and Pixels Room D Origins of Planetary Systems: Drag and Hard Bodies Thursday Morning, 8:30 a.m. Room A Mars: Holes, History, and Hematite Room B Chondrule Petrogenesis Room C Astrobiology Room D Outer Body Experiences Thursday Afternoon, 1:30 p.m. Room A Venus Geophysics and Geology Room B Origins of Chondri tic Metal Room C Europa Room D Mars: Dirt, Dust, and Air Thursday Evening, 7:00-9:30 p.m. UHCL Poster Session II Astrobiology The "Dirt" on Mars Mars Meteorology Martian Magnetics New Meteorites Integrated Lunar Science at the Hard Rock Cafe Presolar Grains Playing the Lunar Crustal Record: My Darling Carbonaceous Chondrites Clementine Enstatite Chondrites Venus Geology and Geophysics Ordinary Chondrites Formation of the Solar System Cosmogenic Nuclides Stardust: Collected, Remote, and Captured The Angry Red Planet Europa Mars: The Other Red Meat Small Body Melange Holey Mars! Surface Processes Friday Morning, 8:30 a.m. Room A Presolar Grains Room B Mars Surface: Remote Sensing Room C Astrobiology: Meteorites Room D Planetary Volcanism: Flows and Edifices Session dedicated to the memory of Peter Francis * Designates Speaker Room A - Gilruth Room 104 Room B- Gilruth Old Gym Room C- Gilruth New Gym Room D- Gilruth Room 206 UHCL- University of Houston-Clear Lake, Bayou Building Monday, March 13,2000 MARTIAN METEORITES I 8:30 a.m. Room A Chairs: M. Wadhwa J. D. Gilmour WadhwaM. * Quantitative Constraints on the Redox State of Martian Magmas from Eu Anomalies in Pyroxenes of Basaltic Shergottites [#1966] In this work, a quantitative method for determining thefo2 of basaltic shergottite parent magmas is presented. Implications are presented for the oxidation state of the source of the parent melts of the basaltic shergottites in the Mars mantle. McKay G. * Mikouchi T. Le L. Schwandt C. Hashimoto M. The Shergotty Paradox: An Experimental Perspective on lntercumulus Melt Compositions [#2000] Experiments on a petrographic estimate of Shergotty intercumulus melt (ICM) composition suggest it is not a good analog for the Shergotty ICM. Changes in P andfo2 do not improve the match. The origin of this mismatch remains an unresolved paradox. Rubin A. E.* Warren P. H. Greenwood J.P. Verish R. S. Leshin L.A. Hervig R. L. Petrology of Los Angeles: A New Basaltic Shergottite Find [#1963] Los Angeles is a new basaltic shergottite find with -46 vol% maskelynite and -40 vol% pyroxene that is more ferroan than that in QUE94201. Augite exsolution lamellae are coarser than in Shergotty or Zagami. Martian origin is indicated by petrography and high D/H ratio. Warren P. H.* Greenwood J. P. Richardson J. W. Rubin A. E. Verish R. S. Geochemistry of Los Angeles, a Ferroan, La- and Th-rich Basalt from Mars [#2001] The Los Angeles shergottite resembles Shergotty and Zagami, but is by far the most ferroan, La-rich, and Th-rich rock yet from Mars. The smaller of two stones appears subtly different in composition, with higher proportions of late-stage components. Borg L. E.* Nyquist L. E. Wiesmann H. Reese Y. Papike J. J. Sr-Nd Isotopic Systematics of Martian Meteorite DaG476 [#1036] The martian meteorite DaG476 is determined to have a Sm-Nd age of 474±11 Ma and an initial fNd value of +36.6±0.8. Wadhwa M. Lentz R. C. F. McSween H. Y. Jr. Crozaz G.* Dar Al Gani 476 and Dar Al Gani 489, Twin Shergottites from Mars [#1413] Two martian meteorites, DaG 476 and DaG 489, were recently recovered from the Libyan Sahara. Here, we present a combined mineralogic-petrologic and ion microprobe study, which confirms that these two meteorites are likely to be paired. 31st LPSC Program 1 Greshake A. * Stoffler D. Shock Related Melting Phenomena in the SNC Meteorite Dar Al Gani 476 [#1043] Dar al Gani 476 contains unusual regions of shock melting which are very different from melt veins in other meteorites. It is suggested that melting here is caused by primary pores whose extremely low shock impedance caused a very high and localized thermal peak. Herd C. D. K. * Jones J. H. Papike J. J. Experimental Constraints on the Cr Content, Oxygen Fugacity, and Petrogenesis of EETA79001 Lithology A [#1387] Experiments involving the composition of the groundmass ofEETA79001 Lithology A constrain the Cr content of the melt and the oxygen fugacity, and suggest that overgrowth of olivine and pyroxene from the groundmass onto xenocrysts has occurred.