This study comprises petrologic investigations of the lunar meteorite Northeast Africa (NEA) 001 and 16 fragments from the Apollo 12 soil 12003. These samples are examples of the variety of materials found in lunar feldspathic highland and mare regoliths, and provide insights into the petrogenesis of different lithologies and regolith mixing processes. They have been analysed by electron microprobe and laser ablation inductively coupled plasma mass spectrometry. NEA 001 is a feldspathic regolith breccia containing clasts of multiple lithologies including; feldspathic impact melt, ferroan noritic anorthosite, magnesian feldspathic clasts and low-Ti and very-low-Ti (VLT) basalts. Feldspathic impact lithologies in NEA 001 are more mafic than estimations for the composition of the upper feldspathic lunar crust, indicating that they have incorporated more mafic lower crustal material. The VLT basalt clasts have low incompatible trace elements (ITE) concentrations, and may represent products of primitive basaltic volcanism. The feldspathic nature of the sample, low-ITE concentrations, and the presence of magnesian feldspathic clasts suggest that the meteorite has been sourced from the Outer-Feldspathic Highlands Terrane, probably on the lunar farside. Apollo 12 landed in the eastern region of Oceanus Procellarum. Previous studies of Apollo 12 samples identified three major basaltic suites (olivine, ilmenite and pigeonite basalts) local to the region. Examples of all three of these have been identified within the 12003 soil collected near the Lunar Module. Two samples are identified as possibly representing a previously unrecognised basaltic suite. One sample is identified as a possible addition to the feldspathic suite; a potential fourth basaltic suite currently consisting of only one other sample. Three non-igneous samples are identified, including two breccias and one impactite. The petrologic analysis of these samples forms part of an ongoing basaltic diversity study which will also include radioisotope dating of these and other Apollo 12 soil samples.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:587646 |
| Date | January 2012 |
| Creators | Snape, J. F. |
| Publisher | University College London (University of London) |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://discovery.ucl.ac.uk/1381931/ |
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