Potential for clastic-dominated and skarn copper-deposits in the Carajás domain (PA): the example of the açaí and angelica deposits

• Grant number: 18/00066-5
• Support Opportunities: Scholarships in Brazil - Master
• Start date: April 01, 2018
• End date: February 29, 2020
• Field of knowledge: Physical Sciences and Mathematics - Geosciences - Geology
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Roberto Perez Xavier
• Grantee: Kamila Gomes Fernandes
• Host Institution: Instituto de Geociências (IG). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

The Carajás Mineral Province is an important Archean domain located in the southwestern Amazonian Craton in Brazil. The Carajás Province is subdivided into two domains: the Rio Maria and Carajás. Volcanosedimentary sequences, which are attributed to the Itacaiúnas Supergroup (ca 2.75 Ga), along with Neoarchean mafic and felsic intrusive rocks (ca 2.75 Ga) and Mesoarchean rocks of the basement host different types of copper systems in the Carajás Domain. These copper systems include iron oxide copper-gold (IOCG), Cu-polymetallic and, less frequently, volcanic-hosted massive sulfides (VHMS). However, greenfield exploration carried out by VALE in the western sector of the Carajás Domain, a region known as Aquiri, has recognized copper systems with characteristics similar to those of clastic-dominated type (CD type) and skarn deposits. These are the cases of the Acaí and Angélica targets that sits in the geological settings of the Aquiri Group, Itacaiúnas Supergroup. The more comprehensive CD-type copper system is housed in siliciclastic metasedimentary sequences resulting in a chalcopyrite, pyrite and pyrrhotite mineralization. The skarn-type copper deposit, with restricted occurrence, is characterized by the paragenesis diopside - actinolite - garnet - quartz - potassium feldspar and ore association composed of chalcopyrite - pyrite + magnetite + molybdenite. In order to systematically elucidate and evaluate the potential of the Carajás Domain for copper deposits of the CD (covering SEDEX) and skarn types, thereby we propose the geological and metallogenic study of the Açaí and Angélica targets by means of (1) characterization of the country rocks, areas of hydrothermal alteration as well as associated copper mineralization; (2) U-Pb geochronology of host and intrusive rocks; (3) analysis of stable isotopes of S, C and O of the mineral assemblage representative of each mineralization event; (4) analysis of fluid inclusions in quartz crystals from the mineralized zones. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

FERNANDES, KAMILA G.; XAVIER, ROBERTO P.; MORETO, CAROLINA P. N.; MELO, GUSTAVO H. C.; BOYCE, ADRIAN J.. The Hydrothermal Evolution of the Alvo Acai Cu (Au, Mo) Skarn Deposit, Carajas Province, Brazil. ECONOMIC GEOLOGY, v. 118, n. 2, p. 25-pg., 2023-03-01. (16/13162-7, 18/00066-5)

Academic Publications

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

FERNANDES, Kamila Gomes. The Alvo Açaí Deposit: an example of a copper skarn in the Carajás Domain. 2020. Master's Dissertation - Universidade Estadual de Campinas (UNICAMP). Instituto de Geociências Campinas, SP.