SPP 1385 - WP: Early evolution of meteorite parent bodies – Hf-W and U-Pb ages of zircons, baddeleyites, and phosphates

Basic data for this project

Description

Generally, ages for meteorites are obtained on mineral separates of bulk rock samples. However, many meteorites are breccias consisting of fragments that may have formed in different environments and/or at different times. The main aim of this project is to obtain age information on mineralogically well-characterized meteorite lithologies by in-situ Hf-W and U-Pb dating of individual zircons, baddeleyites, and phosphates in thin sections by ion probe techniques and by TIMS analyses on separated individual minerals from thin/thick sections. So far only little is known about the crystallization or cooling ages of individual minerals in meteorites. The proposed project presents an innovative challenge to connect a long-lived with a short-lived isotope system. The ages obtained for the different minerals with different decay systems can be used to constrain the thermal history of the parent body, because of the different closure temperatures of the different systems in the datable minerals. The project includes a detailed search for zircons/baddeleyites and phosphates in thin and thick sections of different meteorite classes, the mineralogical characterization and mineral/isotopic analyses by electron microscopy, electron microprobe and La-ICP-MS and dating by ion probe- and TIMS-techniques