Comparison between different calibration procedures for fission-track dating based on LA-ICP-MS

• Grant number: 14/12249-6
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: October 15, 2014
• End date: December 11, 2014
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Julio Cesar Hadler Neto
• Grantee: Cleber Jose Soares
• Supervisor: Raymond A. Donelick
• Host Institution: Instituto de Física Gleb Wataghin (IFGW). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Institution abroad: Apatite to Zircon Inc, United States
• Associated to the scholarship: 11/21296-0 - Research for reference material or natural apatite for laser ablation in Fission Track Thermochronology or similar, BP.PD

Abstract

The entitled project "Pesquisa por um material de referência ou apatita natural por ablação a laser para Termo Cronologia Por Traço de Fissão ou afins" which is being developed in the Chronology Group-UNICAMP has shown satisfactory results. One of the main results is the determination of a matrix matched reference material for U analysis in the LA-ICP-MS. Such material is fundamental in order to avoid matrix effect when LA-ICP-MS is used. Furthermore, it was developed one calibration procedure which allows determining the fission-track age independently (so called absolute approach). This calibration has shown a satisfactory result when applied in age standard samples. However, work like Donelick et al., 2005 have also shown another calibration procedure which seems to be also adequate. Both researchers are looking for an ideal calibration to be applied in a broad geological context so that can be used routinely in the fission-track laboratory worldwide. Thus, this present project is aimed at comparing both calibration, the presented by Soares et al. (2014) and Donelick et al. (2005). In order to reach only one calibration procedure, both fission-track age equations must be broadly studied. Ideally, we have to separate each term of the fission-track age equations and define their contribution for the accuracy of fission-track age. We expect to define only one calibration procedure together with a protocol for calibration/measurements and then suggest for the fission-track community. Our main goal is to define a standardization of the experimental procedures for LA-ICP-MS, which will allow the comparison between results determined in the worldwide laboratories. Finally, we intend to dating Brazilian samples using the proposed protocol and obtain the geological interpretation. It is important to mention despite of some calibration have been suggested in the literature, there is, until now, any geological geologic application of fission-track when LA-ICP-MS is used. (AU)