Zircon Raman dating: perspectives and integration with classical techniques of Thermochronology

• Grant number: 24/18535-2
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: January 01, 2025
• End date: December 31, 2025
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Airton Natanael Coelho Dias
• Grantee: Bruna Lima Lyrio
• Host Institution: Centro de Ciências e Tecnologias para a Sustentabilidade (CCTS). Universidade Federal de São Carlos (UFSCAR). Sorocaba , SP, Brazil

Abstract

Zircon is a common accessory mineral in igneous, sedimentary, and metamorphic. It is physically and chemically resistant and can "survive" for many geological periods, and in many cases, it provides a record of each geological event submitted during these periods. It incorporates in its structure trace elements such as U, Th, and Pb, which is crucial for geochronological analysis. Its ability to retain information about the thermal history of a source area is of invaluable value in elucidating the geological processes arising from a variety of geodynamic settings. Consequently, it is a mineral commonly applied in different dating techniques such as U-Pb, Lu-Hf, Fission Track Thermochronology (FT), and U-Th/He. These techniques to understand the geo and thermochronology of rocks in a variety of geological environments: orogenic basement rocks, thermochronology using detrital grains in sedimentary rocks for analysis of provenance, and thermal history analysis. A new technique has been developed since 2021: Zircon Raman dating. This new technique has a closure temperature between 260 and 370 ºC, which makes it a complementary technique for FT. Therefore, the objective of this project is to i) implement this technique in the laboratories of the TRACKs Group - DFQM, CCTS/UFSCar, evaluating its potential within intermediate temperature thermochronology; and, ii) to perform a Proof of Concept in primary standard samples for FT and secondary for U-Pb. The selected samples are known as OD-3 from the Kawamoto Granodiorite, Japan, and the Fish Canyon Tuff (FCT) from Colorado, USA. Additionally, the technique will be applied to a third sample (published under the name ZPC) that has previously been dated using U-Pb, FT, and EPMA-FT, but is not regarded as a standard sample. This will be conducted to evaluate the potential of the technique on samples with a more complex geological history.