Isotopic micro analysis of U and Pb in situ in zircons using high resolution mass spectrometer

• Grant number: 05/03198-0
• Support type: Regular Research Grants
• Duration: February 01, 2006 - October 31, 2007
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal researcher: Kei Sato
• Grantee: Kei Sato
• Home Institution: Instituto de Geociências (IGC). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

Isotopic micro-analyses of U and Pb “in situ” in zircon using a sensitive high resolution ion micro probe (SHRIMP) or laser micro-probe coupled to the ICP-MS ones they are capable to look for additional information of geological events in relation to the conventional method using thermal ionization mass spectrometer (TIMS), for example, to obtain different ages between core and the rim from a zircon. The main objective of this project is to know the analytic techniques using laser ablation - Multi Collector - Inductively Coupled Plasma - Mass Spectrometer (LA-MC-ICP-MS) recently installed in Tokyo Institute of Technology (TITech) - Japan. In this project I would like to make the isotopic measures using the new mass spectrometer, LA-MC-ICP-MS, in the samples of the researchers' interest of Geochronological Research Center (CPGeo) of IG-USP. The chosen area would be Atuba Complex in outcrops located in the neighborhoods of the Curitiba city. The isotopic studies have as objective of complementing the previous geochronological works with a dating technique alternative still not available in Brazil. As second objective is to do the first contacts in hardware and in software of the SHRIMP II spectrometer. For the obtaining of this know how, it is opportune to do an initial apprenticeship in National Institute of Polar Research (NIPR) - Tokyo where one encounters installed SHRIMP II. The purpose is to obtain a preliminary KNOW HOW of the instrument, to learn the analytic techniques and to discuss the problems and the difficulties faced to heal the defects happened in SHRIMP of NIPR. The learnings in the modern techniques of isotopic analyses by LA-ICP-MS or SHRIMP will bring in the brief future an immeasurable benefit to CPGeo. (AU)