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Model Pertambangan Emas Rakyat dan Pengelolaan Lingkungan Tambang di Wilayah Desa Paningkaban, Kecamatan Gumelar, Kabupaten Banyumas, Jawa Tengah Aziz, Mochammad
Dinamika Rekayasa Vol 10, No 1 (2014): Dinamika Rekayasa - Februari 2014
Publisher : Jenderal Soedirman University

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.20884/1.dr.2014.10.1.61

Abstract

Industri pertambangan merupakan industri yang penuh kontroversi. Di satu sisi industri pertambangan mempunyai potensi besar untuk menciptakan kemanfaatan bagi masyarakat dan dapat menciptakan perubahan sosial dan ekonomi. Kondisi wilayah Desa Panikaban telah terindikasikan memiliki potensi sumberdaya mineral logam emas dengan adanya kegiatan dan aktivitas penambangan rakyat yang masih berlangsung hingga saat ini. Penambangan emas di Desa Panikaban terkonsentrasi di daerah Gancang, Kedungalang dan Cihonje, dengan dikelola oleh rakyat yang menggunakan teknologi gelundung. Konsentrasi endapan bijih di daerah ini memiliki tipe endapan urat kuarsa, dengan litologi berupa tuf litik, andesit dan batupasir tufan, termasuk dalam Formasi Halang dan Formasi Tapak. Pola penambangan yang diharapkan menggunakan metoda gali-timbun, dengan sistem tambang bawah tanah. Penataan kawasan areal tambang emas rakyat merupakan salah satu tahap persiapan dalam mewujudkan kawasan Wilayah Pertambangan Rakyat (WPR) di Kabupaten Banyumas, selain perlu dibentuknya peran serta masyarakat dan adanya badan usaha/koperasi sebagai pengelolanya. Peningkatan perolehan emas perlu diterapkan teknologi tepat guna yang siap pakai dengan memperhatikan tingkat kesehatan dan keselamatan kerja, selain tentunya mengurangi bahaya kecelakaan dan pencemaran air raksa terhadap air dan tanah.
GEOLOGY AND ORE MINERALISATION OF NEOGENE SEDIMENTARY ROCK HOSTED LS EPITHERMAL GOLD DEPOSIT AT PANINGKABAN, BANYUMAS REGENCY, CENTRAL JAVA, INDONESIA Idrus, Arifudin; Hakim, Fahmi; Warmada, I Wayan; Aziz, Mochammad; Kolb, Jochen; Meyer, Franz Michael
Journal of Applied Geology Vol 7, No 2 (2015): Current Issue
Publisher : Geological Engineering Department Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jag.26981

Abstract

Low suphidation (LS) epithermal gold deposits were recently found in the Paningkaban area, Central Java province, Indonesia, with more than five hundred artisanal gold miners currently operating in the area. This study is aimed to understand the geological factors controlling the gold mineralization and to characterize the alteration and ore mineralogy of the deposit. Several epithermal veins/veinlets trending N–S, NW–SE, and NE–SW are hosted by Tertiary turbiditic volcanoclastic sedimentary rocks of the Halang formation. This formation is composed of looping gradation of sandstone and siltstone units. Pre- and syn-mineralization structures such as extension joints, normal sinitral fault and sinitral fault control the gold mineralization. Fault movements formed dilational jogs manifested by NW-SE-trending en-echelon tension gash veins. Four main alteration zones are identified: (a) phyllic, (b) argillic, (c) sub propylitic and (d) weak subpropylitic. Ore minerals consist of native gold, electrum, native silver, pyrite, chalcopyrite, sphalerite, galena, arsenopyrite, cubanite, marcasite, covellite and tennantite, which are commonly associated withargillic alteration. Vein structures such as massive, swarm and low angle veins, stockwork and veins dispersed in diatreme breccia are present. Normal banded, cockade, crustiform, bladed carbonates as well as, comb and saccharoidal features are the typical vein textures. It is noteworthy that the veins are basically composed of carbonate with minor quartz at gold grades of up to 83 g/t Au. Based on the vein structures and textures, four stages of ore mineralization were developed consisting of (a) early stage (fluidized breccia and quartz vein), (b) middle stage (carbonate base metal), (c) late stage (late carbonate), and supergene stage. Gold mineralization originated mainly during middle and late stages, particularly in association with cockade, crustiform, bladed carbonate base metal veins. Based on those various features, the LS epithermal deposit in the study area is categorized as carbonate-base metalgold mineralization type.
TEKSTUR DAN ZONASI ENDAPAN URAT EPITERMAL DAERAH CIHONJE, KECAMATAN GUMELAR, KABUPATEN BANYUMAS, JAWA TENGAH Isyqi, Isyqi; Aziz, Mochammad; Idrus, Arifudin
JURNAL RISET GEOLOGI DAN PERTAMBANGAN Vol 26, No 1 (2016)
Publisher : Indonesian Institute of Sciences

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2453.821 KB) | DOI: 10.14203/risetgeotam2016.v26.258

Abstract

Daerah Cihonje dan sekitarnya memiliki sistem mineralisasi epitermal yang ditandai dengan kehadiran endapan urat. Endapan urat epitermal terbentuk karena proses pengisian rongga (cavity filling) oleh larutan hidtrotermal. Identifikasi karakteristik endapan urat epitermal perlu dikaji lebih mendalam karena dapat mempermudah kegiatan eksplorasi logam mulia maupun logam dasar. Penelitian ini bertujuan untuk mengetahui karakteristik tekstur urat yang berkembang serta menentukan zona mineralisasi logam mulia dan logam dasar daerah penelitian. Metoda yang digunakan dalam penelitian ini  adalah analisis slab urat, analisis petrografi, analisis mineragrafi serta analisis kadar logam mulia dan logam dasar pada endapan urat dengan menggunakan Atomic Absorption Spectrophotometry (AAS). Hasil penelitian menunjukkan tekstur urat di daerah penelitian dibedakan menjadi empat kelompok yaitu kelompok Lattice Bladed, Cockade, Saccharoidal, dan kelompok Sulfide Banded-Disseminated Sulfide. Tekstur urat yang mengandung logam mulia (emas, perak) terdapat di dalam Zona Super Crustiform – Colloform (CC), sedangkan tekstur urat yang mengandung logam dasar terdapat di dalam Zona Super Crystalline Quartz (X). Hasil analisa mineragrafi menunjukkan kandungan mineral logam yang berasosiasi dengan endapan urat di daerah penelitian adalah pirit, kalkopirit, arsenopirit, sfalerit, galena, emas, dan perak. Hasil analisa AAS menunjukkan kadar emas pada urat di daerah penelitian mencapai 83 ppm. Hal itu membuktikan bahwa daerah penelitian merupakan tempat akumulasi logam mulia dari sitem mineralisasi epitermal yang terjadi. Cihonje and surrounding area have epithermal mineralization system, which is identified by the existence of vein deposits. Epithermal vein deposits are formed by cavity filling of hydrothermal solution. Epithermal vein deposit characteristics need to be identified due to its functionality to localize the precious metal and base metal deposits. This research aimis  to understand the characteristic of vein deposit in this research area. The method used are slab vein analysis, petrography, mineragraphy, and Atomic Absorption Spectrophotometry (AAS). Vein textures in research area are divided into four groups, which are Lattice Bladed Group, Cockade group, Saccharoidal Group, and Sulfide Banded – Disseminated Sulfide group. Vein textures that contain precious metal (gold, silver) is located in the Superzona Crustiform - Colloform (CC). And veins that contain base metal is located in the superzona Crystalline quartz. The mineragraphy analysis showed that vein deposits in this research area has been associated with Pyrite, Chalcopyrite, Arsenopirite, Sphalerit, Galena, Gold, and Silver. The results of AAS analysis showed that vein sample has 83 ppm Au content. That indicated that the research area is the zone of the precious metal accumulation.