345-2 New Insights into the Composition and Texture of Lunar Regolith Using Ultrafast Automated Electron-Beam Analysis

See more from this Division: Topical Sessions
See more from this Session: Living on a Dusty Moon

Thursday, 9 October 2008: 8:15 AM
George R. Brown Convention Center, 310AD

Doug Rickman1, Susan J. Wentworth2, Christian M. Schrader3, Doug Stoeser4, Pieter W.S.K. Botha5, Alan R. Butcher6, Hanna E. Horsch6, Aukje Benedictus6, Paul Gottlieb6 and David McKay7, (1)Marshall Space Flight Center, Code VP61, NASA, Huntsville, AL
(2)ERC/ESC Group, JE23, NASA Johnson Space Center, Houston, TX
(3)BAE Systems-MSFC, Huntsville, AL
(4)Central Region Mineral Resources Team, USGS, Denver, CO
(5)ARMC, Intellection Corporation, Westminster, CO
(6)Intellection Pty Ltd, Milton, Queensland, Australia
(7)Astromaterials Group, NASA Johnson Space Ctr, Houston, TX
Sieved grain mounts of Apollo 16 drive tube samples have been examined using QEMSCAN® - an innovative electron beam technology. By combining multiple energy-dispersive X-ray detectors, fully automated control, and off-line image processing, to produce digital mineral maps of particles exposed on polished surfaces, the result is an unprecedented quantity of mineralogical and petrographic data, on a particle-by-particle basis.

Experimental analysis of four size fractions (500-250 µm, 150-90 µm, 75-45 µm and < 20 µm), prepared from two samples (64002,374 and 64002,262), has produced a robust and uniform dataset which allows for the quantification of mineralogy; texture; particle shape, size and density; and the digital classification of distinct particle types in each measured sample.

These preliminary data show that there is a decrease in plagioclase modal content and an opposing increase in glass modal content, with decreasing particle size. These findings, together with data on trace phases (metals, sulphides, phosphates, and oxides), provide not only new insights into the make-up of lunar regolith at the Apollo 16 landing site, but also key physical parameters which can be used to design lunar simulants, and compute Figures of Merit for each material produced.

See more from this Division: Topical Sessions
See more from this Session: Living on a Dusty Moon