P-T-t PATHS, AND EXHUMATION AND COOLING RATES OF HOT OROGENS - THE CASE STUDY OF NOVA VENÉCIA COMPLEX, ARAÇUAÍ OROGEN

• Grant number: 17/00325-8
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): July 01, 2017
• Effective date (End): August 31, 2019
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Acordo de Cooperação: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Vinícius Tieppo Meira
• Grantee: Lucas Rodrigues Schiavetti
• Host Institution: Instituto de Geociências (IG). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil
• Associated research grant: 16/06114-6 - The Neoproterozoic Earth System and the rise of biological complexity, AP.TEM
• Associated scholarship(s): 18/06011-8 - P-T-t paths, exhumation and cooling rates and Lu-Hf garnet geochronology of hot orogens: a study case on the nova Venécia complex, Araçuaí orogen, BE.EP.MS

Abstract

Orogenic belts characterized by high geothermal gradients at intermediate crustal levels are known as hot orogens and are generally associated with geological processes that occurred during the early stages of Earth evolution. The Araçuaí Orogen, located at the northern Mantiqueira Province, is an example of this type of orogen that exposes rocks from its deeper levels. Near the city of Colatina, Espírito Santo state, occur different groups of rocks from the Araçuaí Orogen, including a wide roadcut which exposes migmatitic paragneisses of the Nova Venécia Complex, intruded by anatetic and noritic rocks. The noritic rocks form a metamorphic aureole within the paragneiss, which enables the establishment of a temporal relationship between two distinct metamorphic stages, as the noritic rocks have Cambrian ages and the regional metamorphism on the paragneisses have Ediacaran ages. Additionally, in the same outcrop, Cretaceous basaltic dykes occur following the Colatina Lineament System in the NNW direction. Due to the quality of the exposure and the presence of different evolutional stages of the Araçuaí Orogen in the same outcrop, the present work proposes systematic petrographic, geothermobarometric and geocronological studies, aiming the understanding of the geological relationships between the studied rocks, the definition of P-T-t paths (Pressure-Temperature-time) for the Nova Venécia Complex and the estimate of exhumation and cooling rates for this particular part of the orogen. The successful estimate of these rates will serve as a basis for discussions regarding the processes involved in the evolution of this particular type of orogen. (AU)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

SCHIAVETTI, Lucas Rodrigues. Metamorphism and geochronology of hot orogens: the Nova Venécia Complex case, Araçuaí Orogen. 2018. Master's Dissertation - Universidade Estadual de Campinas (UNICAMP). Instituto de Geociências Campinas, SP.