Article Per Year (5 Year)
p-Index From 2021 - 2026
0.408
P-Index
This Author published in this journals
All Journal Jurnal Ilmiah Dinamika Rekayasa
Dian Rahma Yoni
Teknik Geologi, Universitas Pembangunan Nasional Veteran Yogyakarta, Kabupaten Sleman, Indonesia

Published : 2 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 2 Documents
Search

 1 
Petrographic Study of The Jampang Formation Rock Unit, Cibenda Area, Ciemas District, Sukabumi Regency, Indonesia Dian Rahma Yoni; Afrilita; Nazla Syafitri Rangkuti; Dimas Putra Yodira
Jurnal Ilmiah Dinamika Rekayasa Vol. 21 No. 2 (2025): Jurnal Ilmiah Dinamika Rekayasa - Juli
Publisher : Engineering Faculty, UNSOED

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20884/1.jidr.2025.21.2.31

Abstract

The Cibenda area, located in Ciemas District, Sukabumi Regency, is part of the Ciletuh Geopark, which has important geological diversity that requires detailed study. This study aims to determine the petrographic characteristics of the main rock units and to compile an interpretation of geological evolution based on microscopic data. The method used is thin section analysis of rock samples taken from the field and observed using a polarizing microscope. There are three main rock units studied, namely the Sandstone Unit, the Breccia Unit, and the Andesite Unit. The analysis results show that the sandstone unit consists of fine- to medium-grained rocks dominated by rock fragments and feldspar, the breccia unit is composed of polymictic components in the form of crystal tuff and sandstone in a sandstone matrix, while the andesite unit shows a porphyritic texture with plagioclase and pyroxene phenocrysts. The results of this study indicate that the depositional process and magmatic intrusion occurred gradually, forming a geological sequence that reflects the evolution from a marine environment to tectonic and magmatic activity in the Cibenda area.
Mineral Parageness of Copper Skarn Deposits in Tambulun Prospect, Sulit Air, West Sumatera Afrilita; Dian Rahma Yoni; Setia Pambudi; Septyo Uji Pratomo; Intan Paramita Haty
Jurnal Ilmiah Dinamika Rekayasa Vol. 21 No. 2 (2025): Jurnal Ilmiah Dinamika Rekayasa - Juli
Publisher : Engineering Faculty, UNSOED

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20884/1.jidr.2025.21.2.32

Abstract

The Tambulun Prospect, Sulit Air, Solok Regency, West Sumatra, is one of the locations indicating the presence of a copper (Cu) skarn mineralization system. This study aims to identify the mineral paragenesis in the skarn system through petrographic and ore microscopic analysis. The skarn formation process is caused by the intrusion of Sulit Air granodiorite that penetrates the Tuhur Formation limestone, resulting in alteration zones in the form of exoskarn (garnet–pyroxene, garnet–pyroxene–wollastonite, pyroxene–quartz ± epidote ± chlorite) and endoskarn (pyroxene–k-feldspar–chlorite–epidote) alteration. Skarn formation is divided into four main stages, namely: (1) isochemical metamorphism, (2) prograde stage with the formation of high-temperature calc-silicate minerals, (3) retrograde stage with the emergence of lower-temperature minerals such as epidote and calcite, and (4) supergene stage. The dominant copper mineralization is chalcopyrite, bornite, covellite, and chalcocite. In the prograde phase, chalcopyrite fills fractures along with quartz veins in the garnet–pyroxene zone. The retrograde phase is characterized by the presence of bornite and chalcocite along with calcite and epidote veins that intersect the garnet–pyroxene–wollastonite alteration zone. The supergene phase shows secondary mineralization such as covellite, hematite, malachite, azurite, and chrysocola that fill fractures and pores in the rock. Understanding mineral paragenesis can explain the hydrothermal evolution of skarn systems and provide information for exploration efforts for economic metal deposits in the surrounding area.
Co-Authors Afrilita Dimas Putra Yodira Intan Paramita Haty Nazla Syafitri Rangkuti Septyo Uji Pratomo Setia Pambudi