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Boy Yoseph Cahya Sunan Sakti Syah Alam
Fakultas Teknik Geologi Universitas Padjadjaran
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GEOLOGI DAN KARAKTERISTIK BIJIH PIT RAMBA JORING DEPOSIT MARTABE, SUMATERA UTARA Arifin, Asri; Rosana, Mega Fatimah; Yuningsih, Euis Tintin; Yoseph, Boy
Buletin Sumber Daya Geologi Vol 14, No 2 (2019): Buletin Sumber Daya Geologi
Publisher : Buletin Sumber Daya Geologi

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1743.098 KB)

Abstract

Deposit Ramba Joring merupakan bagian dari wilayah Kontrak Karya (KK) pertambangan umum PT Agincourt Resources yang terletak di Kelurahan Aek Pining, Kecamatan Batangtoru, Kabupaten Tapanuli Selatan, Provinsi Sumatera Utara. Penelitian ini bertujuan untuk mengetahui kondisi geologi meliputi geomorfologi, stratigrafi dan struktur geologi serta karakteristik bijih yang mengandung emas-perak pada deposit Ramba Joring. Penelitian dilakukan pada 44 lubang bor dan 15 conto permukaan. Penelitian menggunakan metode analisis petrografi sayatan tipis dan poles, Analytical Spectral Devices (ASD), Scanning Electron Microscopy with Energy Dispersive (SEM EDS) serta pengolahan statistik data geokimia assay berupa nilai kadar kandungan Au, Ag, Cu, SxS (sulfide sulphur) yang didapatkan melalui analisis Atomic Absoption Spectrometry (AAS). Daerah penelitian tersusun oleh litologi, diurutkan dari tua ke muda, berupa satuan andesit hornblende dan breksi polimik-monomik. Satuan batuan andesit hornblende dan breksi polimik-monomik teralterasi kuat oleh empat jenis alterasi yaitu, silisifikasi (kuarsa-kalsedon-alunit-kaolinit±dikit), argilik lanjut (alunit±kuarsa-kaolinit±dikit-pirofilit), argilik (ilit±smektit-alunit-kaolinit-kuarsa) dan propilitik (klorit-epidot-kalsit). Terdapat enam jenis mineral sulfida pada daerah penelitian, paragenesa dimulai dari pirit, enargit, tennantit, tetrahedrit dan kovelit bersamaan dengan pengendapan emas-perak serta pirit dengan kristal berbentuk sempurna yang terbentuk paling akhir. Hasil uji pada data assay geokimia menunjukkan adanya korelasi antara kandungan unsur Au, Ag, Cu dan SxS (sulfide sulphur) terhadap jenis alterasi. Diketahui bahwa mineralisasi emas dan logam lainnya berasosiasiasi dengan mineral sulfida yang melimpah pada alterasi silisifikasi namun semakin berkurang pada jenis alterasi argilik hingga menghilang pada alterasi propilitik.
GEOLOGI DAN KARAKTERISTIK BIJIH PIT RAMBA JORING DEPOSIT MARTABE, SUMATERA UTARA Arifin, Asri; Rosana, Mega Fatimah; Yuningsih, Euis Tintin; Yoseph, Boy
Buletin Sumber Daya Geologi Vol. 14 No. 2 (2019): Buletin Sumber Daya Geologi
Publisher : Pusat Sumber Daya Mineral Batubara dan Panas Bumi

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1743.098 KB) | DOI: 10.47599/bsdg.v14i2.247

Abstract

Deposit Ramba Joring merupakan bagian dari wilayah Kontrak Karya (KK) pertambangan umum PT Agincourt Resources yang terletak di Kelurahan Aek Pining, Kecamatan Batangtoru, Kabupaten Tapanuli Selatan, Provinsi Sumatera Utara. Penelitian ini bertujuan untuk mengetahui kondisi geologi meliputi geomorfologi, stratigrafi dan struktur geologi serta karakteristik bijih yang mengandung emas-perak pada deposit Ramba Joring. Penelitian dilakukan pada 44 lubang bor dan 15 conto permukaan. Penelitian menggunakan metode analisis petrografi sayatan tipis dan poles, Analytical Spectral Devices (ASD), Scanning Electron Microscopy with Energy Dispersive (SEM EDS) serta pengolahan statistik data geokimia assay berupa nilai kadar kandungan Au, Ag, Cu, SxS (sulfide sulphur) yang didapatkan melalui analisis Atomic Absoption Spectrometry (AAS). Daerah penelitian tersusun oleh litologi, diurutkan dari tua ke muda, berupa satuan andesit hornblende dan breksi polimik-monomik. Satuan batuan andesit hornblende dan breksi polimik-monomik teralterasi kuat oleh empat jenis alterasi yaitu, silisifikasi (kuarsa-kalsedon-alunit-kaolinit±dikit), argilik lanjut (alunit±kuarsa-kaolinit±dikit-pirofilit), argilik (ilit±smektit-alunit-kaolinit-kuarsa) dan propilitik (klorit-epidot-kalsit). Terdapat enam jenis mineral sulfida pada daerah penelitian, paragenesa dimulai dari pirit, enargit, tennantit, tetrahedrit dan kovelit bersamaan dengan pengendapan emas-perak serta pirit dengan kristal berbentuk sempurna yang terbentuk paling akhir. Hasil uji pada data assay geokimia menunjukkan adanya korelasi antara kandungan unsur Au, Ag, Cu dan SxS (sulfide sulphur) terhadap jenis alterasi. Diketahui bahwa mineralisasi emas dan logam lainnya berasosiasiasi dengan mineral sulfida yang melimpah pada alterasi silisifikasi namun semakin berkurang pada jenis alterasi argilik hingga menghilang pada alterasi propilitik.
Vertical Electrical Sounding Exploration of Groundwater in Kertajati, Majalengka, West Java, Indonesia Nugraha, Gumilar Utamas; CSSSA, Boy Yoseph; Nur, Andi Agus; Pranantya, Pulung Arya; Handayani, Lina; Lubis, Rachmat Fajar; Bakti, Hendra
Indonesian Journal on Geoscience Vol 8, No 3 (2021)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (8000.416 KB) | DOI: 10.17014/ijog.8.3.359-369

Abstract

Continuously increasing population and progressive infrastructural development in the region of Kertajati International Airport, Indonesia, emphasize the need to develop a sustainable water supply network. Airport facilities require sufficient water resources, which can be obtained from surface water and groundwater. Groundwater exploration can provide necessary information for assessing water resources. The purpose of this study is to analyze the configuration of aquifers in the studied area. A Schlumberger array was used to carry out twelve vertical electrical soundings (VES) with AB/2 electrode spacing ranging from 1.5 m to 150 m. IPI2win software was used to qualitatively interpret the VES results and it suggested the presence of three distinct lithological units interpreted as clay, alluvial sand, and a Lower Quaternary formation. In general, resistivity values in the studied area can be divided into five resistivity categories: very low resistivity with values ranging from 1 Ωm to 10 Ωm, low resistivity with values ranging from 10 Ωm to 50 Ωm, medium resistivity with values ranging from 50 Ωm to 100 Ωm, high resistivity with values ranging from 100 Ωm to 200 Ωm, and very high resistivity with values > 200 Ωm. The geo-electric interpretation revealed three geo-electric layers: topsoil (1 - 144 Ω m), sand (1 - 298 Ω m), and clay (1 - 82 Ω m). Aquifers in the studied area are lithologically composed of sand. Clay is the dominant lithology in the studied area, so the presence of aquifers in this area is very limited, and thus the supply of groundwater is also limited. The exploitation of groundwater must be limited and controlled to maintain the sustainability of groundwater in the studied area.
Vertical Electrical Sounding Exploration of Groundwater in Kertajati, Majalengka, West Java, Indonesia Nugraha, Gumilar Utamas; CSSSA, Boy Yoseph; Nur, Andi Agus; Pranantya, Pulung Arya; Handayani, Lina; Lubis, Rachmat Fajar; Bakti, Hendra
Indonesian Journal on Geoscience Vol 8, No 3 (2021): in-press
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.8.3.359-369

Abstract

Continuously increasing population and progressive infrastructural development in the region of Kertajati International Airport, Indonesia, emphasize the need to develop a sustainable water supply network. Airport facilities require sufficient water resources, which can be obtained from surface water and groundwater. Groundwater exploration can provide necessary information for assessing water resources. The purpose of this study is to analyze the configuration of aquifers in the studied area. A Schlumberger array was used to carry out twelve vertical electrical soundings (VES) with AB/2 electrode spacing ranging from 1.5 m to 150 m. IPI2win software was used to qualitatively interpret the VES results and it suggested the presence of three distinct lithological units interpreted as clay, alluvial sand, and a Lower Quaternary formation. In general, resistivity values in the studied area can be divided into five resistivity categories: very low resistivity with values ranging from 1 Ωm to 10 Ωm, low resistivity with values ranging from 10 Ωm to 50 Ωm, medium resistivity with values ranging from 50 Ωm to 100 Ωm, high resistivity with values ranging from 100 Ωm to 200 Ωm, and very high resistivity with values > 200 Ωm. The geo-electric interpretation revealed three geo-electric layers: topsoil (1 - 144 Ω m), sand (1 - 298 Ω m), and clay (1 - 82 Ω m). Aquifers in the studied area are lithologically composed of sand. Clay is the dominant lithology in the studied area, so the presence of aquifers in this area is very limited, and thus the supply of groundwater is also limited. The exploitation of groundwater must be limited and controlled to maintain the sustainability of groundwater in the studied area.
KARAKTERISTIK FLUIDA PEMBAWA MINERALISASI PIT RAMBA JORING DEPOSIT MARTABE, SUMATRA UTARA: MINERALIZATION BEARING FLUID CHARACTERISTIC OF RAMBA JORING PIT MARTABE DEPOSIT, NORTH SUMATRA Arifin, Asri; Rosana, Mega Fatimah; Yuningsih, Euis Tintin; Yoseph CSSSA, Boy
Buletin Sumber Daya Geologi Vol. 16 No. 2 (2021): Buletin Sumber Daya Geologi
Publisher : Pusat Sumber Daya Mineral Batubara dan Panas Bumi

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.47599/bsdg.v16i2.314

Abstract

The research aims to determine hydrothermal evolution of the mineralisation bearing fluid contained in the Ramba Joring Pit, including temperature, pressure, density and depth of mineralisation deposition formation. This research uses the fluid inclusion analysis. Inclusion sampling was carried out on two main textures of ore namely vuggy silica texture formed at range Th 331ºC to 394ºC, Tm -15.19ºC to -12.94ºC with salinity of 14.42 wt% - 14.89 wt%. NaCl equivalent and brecciated texture formed at range Th 287.8ºC – 398.2ºC, Tm -14.89ºC to -11,76ºC and salinity 13.91 wt% – 14.87 wt%. NaCl equivalent. The positive correlation between the homogenization temperature of mineralization formation and salinity of the solution indicates that the leaching process that forms cavities in rocks occurs at the initial stage of the hydrothermal alteration process that begins with the leaching process forming cavities (silica vuggy) followed by the process of silicification with brecciated texture, the deposition of mineralization takes place at this stage. The origin of the solution forms a hydrothermal deposition is a type of basinal water-seawater solution in the form of connate water which is still influenced by surface water/meteoric water, also shows an indication of a relationship with magmatic water. The density of metal-forming fluids ranges from 0.8 gr/cm3 – 0.9 gr/cm3 while the process that takes place in the formation of ore in Ramba Joring Pit is isothermal mixing with a slight warming effect/boiling.
Identifikasi Zona Infiltrasi Airtanah di Kawasan Karst Berdsarkan Nilai Tekanan Parsial CO2 dan Indeks Kejenuhan CaCO3 (SIc) di Sekitar Perbukitan Karst Watuputih Nofi Muhammad Alfan Asghaf; Boy Yoseph CSSS Alam; Hendarmawan Hendarmawan
Jurnal Lingkungan dan Bencana Geologi Vol 10, No 2 (2019)
Publisher : Badan Geologi

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2631.119 KB) | DOI: 10.34126/jlbg.v10i2.251

Abstract

Persebaran mata air di sekitar perbukitan karst Watuputih menunjukkan kawasan tersebut memiliki potensi air tanah yang tinggi. Kehadiran mata air karst tersebut sebagai akibat dari kondisi geologi yang didominasi oleh batuan karbonat yang mudah larut dan struktur geologi yang intensif. Penelitian ini bertujuan untuk mengetahui karakteristik daerah infiltrasi air tanah berdasarkan analisis tekanan parsial CO2 (Pco2) dan indeks kejenuhan CaCO3 (SIc), dikombinasikan dengan analisis fasies kimia air tanah dan kelurusan morfologi. Hasil analisis menunjukkan, pada densitas kelurusan morfologi tinggi memiliki nilai Pco2 rendah dan air tanah dalam kondisi jenuh sedangkan pada densitas kelurusan morfologi rendah nilai Pco2 tinggi dan air tanah dalam kondisi jenuh hingga tidak jenuh. Korelasi Pco2 dengan SIc dikombinasikan dengan kondisi geologi dan fasies kimia air tanah menghasilkan tiga tipe mata air, yaitu (1) Nilai Pco2 tinggi, nilai SIc jenuh hingga tidak jenuh, fasies hidrokimia dominan Ca-Mg-HCO3, densitas morfologi rendah, lapisan soil tebal, dan media aliran air tanah dominan jaringan pori memiliki infiltrasi rendah; (2) Nilai Pco2 rendah, nilai SIc jenuh, fasies hidrokimia dominan Ca-HCO3, densitas morfologi tinggi, lapisan tanah tipis, dan media aliran air tanah dominan jaringan pori dan rekahan batuan yang rapat, tetapi mulai berkembang jaringan rongga, memiliki infiltrasi tinggi; dan (3) Nilai Pco2 sangat tinggi, nilai SIc tidak jenuh, fasies hidrokimia Ca-Na-HCO3 dan Ca-Mg-Cl-HCO3, densitas morfologi tinggi, lapisan soil tebal, media aliran air tanah jaringan pori, dan litologi batuan nonkarbonatan, memiliki infiltrasi rendah.
HYDROGEOLOGICAL IDENTIFICATION OF THE WELARAN WATERSHED KARANGSAMBUNG BASED ON DESCRIPTIVE-QUALITATIVE METHOD Nandian Mareta; Rachmat Fajar Lubis; Boy Yoseph CSS Syah Alam; Mohammad Sapari Dwi Hadian
JURNAL RISET GEOLOGI DAN PERTAMBANGAN Vol 31, No 1 (2021)
Publisher : Indonesian Institute of Sciences

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.14203/risetgeotam2021.v31.1144

Abstract

The Welaran watershed in the Karangsambung area is hydrogeologically interesting because of its morphology, “U” shaped morphology like an amphitheater with the lithology consisting of tertiary to quarternary rocks. The character of Welaran river is an intermittent river that watery during the rainy season and dry during the dry season. This study intended to identify and determine the general hydrogeological condition of the Welaran watershed on a scale of 1:20.000. This study applies a descriptive-qualitative research method. The steps used are hydrogeological analysis and water balance. The results obtained indicate that the hydrogeological conditions of the area affect the character of the rivers in t   
HIDROGEOKIMIA AIRTANAH PADA DAERAH PANTAI: STUDI KASUS DATARAN RENDAH KATAK, DESA SUMBER AGUNG, KABUPATEN BANYUWANGI Arief Nur Muchamad; Boy Yoseph CSS Syah Alam; Euis Tintin Yuningsih
JURNAL RISET GEOLOGI DAN PERTAMBANGAN Vol 27, No 1 (2017)
Publisher : Indonesian Institute of Sciences

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1024.372 KB) | DOI: 10.14203/risetgeotam2017.v27.442

Abstract

This paper describes the groundwater quality assessment conducted in Katak lowland area, in Banyuwangi District, East Java. The quality of water salinity had been identified during field observation. In order to identify the origin of saline groundwater, a hydrogeochemical study has been carried out by analysing of 12 groundwater wells, 3 surface water and sea water. Hydrogeochemical analysis identified major ion elements on Piper′s diagram to know the facies and dominant ion content in ground water study area. The interpretation of plots for different major ions suggests that saline water in Katak are typically salt water intrusion and flushing salt residue in marine sediment/limestone. This hydrochemical research area provides new insights into the geochemical relationships between freshwater and seawater at different depths in coastal and alluvial sediments. Saltwater intrusion occurs due to cone of depression caused by concentrated exploitation of groundwater in the south/coastal area, and flushing mainly by groundwater flow through marine sediment/limestone in the northern area. Groundwater zonation is characterized by hydrochemical type from natrium chloride type in the southern area to calciumsulphate  type in the northern  area. Controlled by hydrodynamic of groundwater with salt water and flushing of geochemical by ground water, respectively. AbstrakMakalah ini menjelaskan hasil dari penilaian kualitas airtanah yang dilakukan di daerah dataran rendah Katak, di Kabupaten Banyuwangi, Jawa Timur. Kualitas airtanah yang asin telah teridentifikasi saat observasi lapangan. Dalam rangka mengidentifikasi asal air asin di daerah Katak, studi hidrogeokimia dilakukan terhadap sampel airtanah dari 12 airtanah sumur/bor, 3 air permukaan dan air laut. Analisis hidrokimia dilakukan dengan pengeplotan unsurunsur ion utama pada diagram Piper untuk mengetahui fasies dan kandungan ion dominan pada airtanah di daerah penelitian. Interpretasi plot untuk ion utama menunjukkan bahwa salinitas di daerah Katak diakibatkan oleh intrusi air laut dan pembilasan garam-garam pada sedimen marine/batugamping. Penelitian hidrokimia di daerah dataran rendah Katak memberikan wawasan baru mengenai hubungan antara air tawar dan air laut pada kedalaman yang berbeda di dalam sedimen pantai dan aluvial. Intrusi air asin terjadi karena kerucut depresi yang disebabkan oleh eksploitasi air tanah terkonsentrasi di bagian selatan yang merupakan daerah pesisir dan pembilasan karena aliran air tanah melalui sedimen marine/batugamping di Utara. Zonasi jenis airtanah diketahui dari karakteristik hidrokimianya, mulai dari jenis natrium klorida di Selatan sampai kalium sulfat di Utara. Hal tersebut masing-masing dikontrol oleh hidrodinamika airtanah dengan air asin dan pelarutan kimia batuan oleh airtanah.
Vertical Electrical Sounding Exploration of Groundwater in Kertajati, Majalengka, West Java, Indonesia Gumilar Utamas Nugraha; Boy Yoseph CSSSA; Andi Agus Nur; Pulung Arya Pranantya; Lina Handayani; Rachmat Fajar Lubis; Hendra Bakti
Indonesian Journal on Geoscience Vol 8, No 3 (2021)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.8.3.359-369

Abstract

DOI:10.17014/ijog.8.3.359-369Continuously increasing population and progressive infrastructural development in the region of Kertajati International Airport, Indonesia, emphasize the need to develop a sustainable water supply network. Airport facilities require sufficient water resources, which can be obtained from surface water and groundwater. Groundwater exploration can provide necessary information for assessing water resources. The purpose of this study is to analyze the configuration of aquifers in the studied area. A Schlumberger array was used to carry out twelve vertical electrical soundings (VES) with AB/2 electrode spacing ranging from 1.5 m to 150 m. IPI2win software was used to qualitatively interpret the VES results and it suggested the presence of three distinct lithological units interpreted as clay, alluvial sand, and a Lower Quaternary formation. In general, resistivity values in the studied area can be divided into five resistivity categories: very low resistivity with values ranging from 1 Ωm to 10 Ωm, low resistivity with values ranging from 10 Ωm to 50 Ωm, medium resistivity with values ranging from 50 Ωm to 100 Ωm, high resistivity with values ranging from 100 Ωm to 200 Ωm, and very high resistivity with values > 200 Ωm. The geo-electric interpretation revealed three geo-electric layers: topsoil (1 - 144 Ω m), sand (1 - 298 Ω m), and clay (1 - 82 Ω m). Aquifers in the studied area are lithologically composed of sand. Clay is the dominant lithology in the studied area, so the presence of aquifers in this area is very limited, and thus the supply of groundwater is also limited. The exploitation of groundwater must be limited and controlled to maintain the sustainability of groundwater in the studied area.
Sistem Akuifer Air Tanah Daerah Sukamoro Kabupaten Banyuasin - Sumatera Selatan Deden Zaenudin Mutaqin; Undang Mardiana; Febriwan Mohammad; Muhammad Kurniawan Alfadli; Boy Yoseph CSSSA
Dinamika Rekayasa Vol 17, No 2 (2021): Jurnal Ilmiah Dinamika Rekayasa - Agustus 2021
Publisher : Jenderal Soedirman University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20884/1.dr.2021.17.2.349

Abstract

Studi sistem akuifer hidrogeologi sangat penting untuk dilakukan dalam rangka mengidentifikasi kondisi geologi dan hidrogeologi. Lokasi daerah penelitian termasuk ke dalam daerah bukan cekungan air tanah, tetapi kondisi visual di lapangan menunjukkan penduduk sekitar banyak memanfaatkan air tanah cukup besar. Metode yang digunakan berupa penyelidikan geologi, geolistrik 2-D konfigurasi Wenner – Schlumberger dan hidrogeologi. Tujuan dari penelitian ini yaitu mengetahui sistem akuifer  daerah Sukamoro.  Di daerah Sukamoro terdapat dua sistem akuifer, yaitu pada endapan rawa (satuan lanau) berupa sistem dengan aliran antar butir; merupakan sistem airtanah tidak tertekan, dengan nilai TDS yang acak dengan nilai resistivitas di bawah 40 Ohm meter, berada pada bagian Selatan daerah penyelidikan. Pada satuan perselingan batupasir dengan batulempung yang memiliki sistem akuifer dengan aliran melalui ruang antar butir dan rekahan, merupakan sistem airtanah tidak tertekan dan tertekan,  dengan nilai TDS  antara 80-240 mg/L dan di bawah 80 mg/L, dengan nilai resistivitas 41-450 Ohm meter
Co-Authors Andi Agus Nur Arief Nur Muchamad Asri Arifin Bakti, Hendra Deden Zaenudin Mutaqin Emi Sukiyah Endah, Raras Euis Tintin Yuningsih Febriwan Mohammad Gumilar Utamas Nugraha Hadi Hidayat Handayani, Lina Hendarmawan Hendarmawan Hendra Bakti Iskandarsyah, Teuku Yan W. M. Lina Handayani Lubis, Rachmat Fajar Mega Fatimah Rosana Mohammad Sapari Dwi Hadian Muda Iskandarsyah, Teuku Yan Waliana Muhammad Kurniawan Alfadli Nandian Mareta Nofi Muhammad Alfan Asghaf Nugraha, Gumilar Utamas Pranantya, Pulung Arya Pulung Arya Pranantya Rachmat Fajar Lubis Rachmat Fajar Lubis Septio, Ghenady Taat Setiawan, Taat Ulfa Yusti Undang Mardiana Wijaya, Dwi Suyandi Pasa