Japan Geoscience Union Meeting 2022

Presentation information

[J] Poster

H (Human Geosciences ) » H-RE Resource and Engineering Geology

[H-RE13] Resource Geology

Thu. Jun 2, 2022 11:00 AM - 1:00 PM Online Poster Zoom Room (16) (Ch.16)

convener:Tsubasa Otake(Division of Sustainable Resources Engineering, Faculty of Engineering, Hokkaido University), convener:Kenzo Sanematsu(Mineral Resource Research Group, Institute for Geo-Resources and Environment, Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology), Ryohei Takahashi(Graduate School of International Resource Sciences, Akita University), convener:Tatsuo Nozaki(Submarine Resources Research Center, Research Institute for Marine Resources Utilization, Japan Agency for Marine-Earth Science and Technology), Chairperson:Tsubasa Otake(Division of Sustainable Resources Engineering, Faculty of Engineering, Hokkaido University)

11:00 AM - 1:00 PM

[HRE13-P01] Geology and geochemistry of the metavolcanic host rocks at the mugomo gold prospect, Tete province, Mozambique

*Euclesia Paulina Francisco Cossa1, Andrea Agangi1, Ryohei Takahashi1, Pearlyn Manalo1, Akira Imai2, Vicente Manjate3 (1.Akita University, Japan, 2.Kyushu University, Japan, 3.National Mining Institute, Mozambique)

Keywords:Mesoproterozoic, Shear zone, Mozambique, Volcanic arc, Ore minerals

The Mugomo gold prospect is located close to N-S trending fractures and is associated with shear zones. The studied area belongs to the southern part of Irumide Belt consisting of the Proterozoic Mualadzi Group and Furancungo Suite.
A mineralization model for Mugomo prospect has not been understood and the processes of mineralization remain unknown. Hence, the goal of this study is to characterize the geology, type of mineralization, hydrothermal alteration, veins and ore minerals related to it. In the Mugomo prospect, metavolcanic rocks, schist, and quartizite are crosscut by quartz veins as well as epidote veins and veinlets.
Pyrite, chalcopyrite, sphalerite, galena and bornite with minor Ag-Te and Bi-Te minerals occur within the quartz-epidote veins, as well as dissemination in the metavolcanic rocks and quartzite. Petrographic observations and ICP-MS analysis revealed elevated concentrations of Ag, Au, Bi and Te in metavolcanic rocks, quartzite, and epidote-quartz veins.
Primary minerals in the metavolcanic rocks are epidote, albite, and calcite. The schist is composed of medium-fine-grained, biotite and quartz, which form the foliation, and the quartzite is mainly composed of quartz and minor biotite minerals.
The metavolcanic rocks are classified as a calc-alkaline rhyolite in composition based on the alkali and SiO2 contents and are characterized by their significant enrichment of LREE and depletion of HREE and Eu. The trace element data plotted on the Rb and Y+Nb discrimination diagram suggest that the rhyolite was formed in the volcanic arc setting.