Insights into thermo-tectonic evolution of the Alexander Island, Antarctic Peninsula using Fission Track Thermochronology in zircon

• Grant number: 23/13974-5
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: June 01, 2024
• End date: December 31, 2024
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Principal Investigator: Airton Natanael Coelho Dias
• Grantee: Lucas Alexander Nunes
• Host Institution: Centro de Ciências e Tecnologias para a Sustentabilidade (CCTS). Universidade Federal de São Carlos (UFSCAR). Sorocaba , SP, Brazil

Abstract

The thermo-tectonic evolution of the Antarctic Peninsula is still little known. Studies in the area are being developed but with the application of techniques only within the context of geochronology that allows us to determine the age of earth materials by determining the abundance of the parent and daughter isotopes of a given isotopic system in a mineral. Using this method, such as U-Pb, Lu-Hf, and others, it is possible to date the origin and emplacement of plutonic or volcanic rocks or sediment deposits can be determined. However, there is no record of thermochronological data (intermediate-low temperatures) that could identify the phenomena that occurred after the formation of rocks, i.e., denudation events, and uplifts, among others. Therefore, in this project, Fission Track Thermochronology (FTT) will be applied to zircon samples from Alexander Island, Antarctic Peninsula to reconstruct and understand its thermo-tectonic evolution. This is a methodology suitable for resolving significant uncertainties in the age of igneous and sedimentary components on the island. In this way, it is understood that it will be possible to obtain insights into the evolution of the area and cooperate in understanding the tectonic processes that took place during the Mesozoic. 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, provides a record of each geological event that was submitted in these periods. 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, Zircon Fission Track Thermochronology has been extensively used in combination with other methods of radiometric dating such previously mentioned.