Quantitative study of microstructures and microtextures of Ol-Diogenites (Harzburgites and Dunites). Eyewitnesses of early mantle processes in Vesta-like asteroids

• Applicant: Professor Dr. Frank Erich Brenker
• Subject Area: Mineralogy, Petrology and Geochemistry
• Term: from 2014 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 248756347

Based on our unpredicted finding of solid state plastic deformation via pencil glide during our preliminary work on the harzburgitic diogenite NWA 5480, which will have several far reaching consequences on the thermal history, chemical and structural equilibration in the early stages of asteroid formation, we propose to perform a comprehensive quantitative structural and textural study of olivine-rich diogenites (harzburgites and dunites) which most likely represent mantle rocks originated from the differentiated Vesta or a Vesta-type asteroid.For the first time a characterization and quantification of the complete micro and nano structural inventory of this rare rock type will be performed. This enables to unravel details of the thermal and structural evolution and some cases the effective deformation mechanism. A combination of electron backscatter diffraction (EBSD) and large area transmission electron microscopic (TEM) will be applied in order to measure details of the crystallographic preferred orientation and relate them to texture forming processes like crystallization, compaction, shock effects and deformation mechanism. In the broader framework of NASAs Dawn mission to Vesta this study will help to better understand the formation mechanism and evolution of differentiated asteroids.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1385: The first 10 Million Years of the Solar System - A Planetary Materials Approach
• International Connection: USA
• Participating Person: Professor Dr. Tony Irving