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Characteristics and Origin of Sedimentary-Related Manganese Layers in Timor Island, Indonesia Idrus, Arifudin; Ati, E. M.; Harijoko, A.; Meyer, F. M.
Indonesian Journal on Geoscience Vol 8, No 4 (2013)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2452.311 KB) | DOI: 10.17014/ijog.v8i4.169

Abstract

DOI: 10.17014/ijog.v8i4.169Sedimentary-related manganese layers have been discovered in South Central Timor Regency, Timor Island, Indonesia, which is tectonically active and being uplifted due to north-trending tectonic collision between Timor Island arc and Australian continental crust. The manganese layers of 2 to 10 cm-wide interbed with deep sea sedimentary rocks including reddish - reddish brown claystone, radiolarian chert, slate, marl as well as white and pinkish calcilutite of Nakfunu Formations. Stratigraphically, the rock formations are underlain by Bobonaro Formation. Two types of manganese ores found comprise manganese layers and manganese nodule. The manganese layers strongly deformed, lenticular, and segmented, are composed of manganite [MnO(OH)], groutite [MnO(OH)], pyrolusite (MnO2), lithioporite (Al,Li) MnO2(OH)2, and hollandite [Ba (Mn4+, Mn2+)8O16] associated with gangue minerals including calcite, quartz, limonite [FeO(OH)], hematite (Fe2O3), and barite (BaSO4). Whilst the nodule type is only composed of manganite and less limonite. Geochemically, the manganese layers have grade of 63 - 72 wt.% MnO, whereas the nodule one has grade of 63 - 69 wt.% MnO. Generally, iron in Mn ore is very low ranging from 0.2 to 1.54 wt.% Fe2O3, averaged 0.76 wt.%. Hence, Fe/Mn ratio which is very low (0.003 - 0.069), typically indicates a sedimentary origin, which is also supported by petrologic and petrographic data showing layering structure of manganite and lithioporite crystal/grain. Trace element geochemistry indicates that manganese ore was precipitated in a reduction condition. Rare earth element (REE) analysis of manganese ore shows an enrichment of cerium (Ce) suggesting that the ore is basically originated in a marine environment. The manganese nodule is interpreted to be formed by chemical concretion process of unsoluble metals (i.e. mangan, iron) in seawater (hydrogenous) and precipitated on deep sea bottom. On the other hand, the manganese layer is a detrital diagenetic deposit formed by Mn remobilization in seawater column, precipitated and sedimented on the deep sea bottom. Manganese layers have probably been influenced by ‘hydrothermal process’ of mud-volcano activities, proven by the presence of quartz and barite veinlets cutting the Mn layers, manganite recrystallization to be pyrolusite along veinlets cutting manganite and lithioporite layers, and the presence of pyrite and sulphur associated with Mn layers. Field data also exhibit that the significant manganese layers are mostly found around mud volcanoes. The closely spatial and genetic relationships between manganese layers and mud-volcanoes might also be an important guide for the exploration of Mn deposit in the region.
Some Key Features and Possible Origin of the Metamorphic Rock-Hosted Gold Mineralization in Buru Island, Indonesia Idrus, Arifudin; Prihatmoko, Sukmandaru; Hartono, Hill. Gendoet; Idrus, Fadlin; Ernowo, Ernowo; Franklin, Franklin; Moetamar, Moetamar; Setiawan, Iwan
Indonesian Journal on Geoscience Vol 1, No 1 (2014)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (998.411 KB) | DOI: 10.17014/ijog.v1i1.172

Abstract

DOI: 10.17014/ijog.v1i1.172This paper discusses characteristics of some key features of the primary Buru gold deposit as a tool for a better understanding of the deposit genesis. Currently, about 105,000 artisanal and small-scale gold miners (ASGM) are operating in two main localities, i.e. Gogorea and Gunung Botak by digging pits/shafts following gold-bearing quartz vein orientation. The gold extraction uses mercury (amalgamation) and cyanide processing. The field study identifies two types/generations of quartz veins namely (1) Early quartz veins which are segmented, sigmoidal, dis­continous, and parallel to the foliation of host rock. The quartz vein is lack of sulfides, weak mineralized, crystalline, relatively clear, and maybe poor in gold, and (2) Quartz veins occurred within a ‘mineralized zone’ of about 100 m in width and ~1,000 m in length. The gold mineralization is strongly overprinted by an argillic alteration zone. The mineralization-alteration zone is probably parallel to the mica schist foliation and strongly controlled by N-S or NE-SW-trending structures. The gold-bearing quartz veins are characterized by banded texture particularly colloform following host rock foliation and sulphide banding, brecciated, and rare bladed-like texture. The alteration types consist of propylitic (chlorite, calcite, sericite), argillic, and carbonation represented by graphite banding and carbon flakes. The ore mineralization is characterized by pyrite, native gold, pyrrhotite, and arsenopyrite. Cinnabar, stibnite, chalcopyrite, galena, and sphalerite are rare or maybe absent. In general, sulphide minerals are rare (<3%). Fifteen rock samples were collected in Wamsaid area for geochemical assaying for Au, Ag, As, Sb, Hg, Cu, Pb, and Zn. Eleven of fifteen samples yielded more than 1.00 g/t Au, in which six of them are in excess of 3.00 g/t Au. It can be noted that all high-grade samples are originally or containing limonitic materials, that suggest the role of supergene enrichment. Interestingly, most of the high-grade samples contain also high grade As (up to 991ppm), Sb (up to 885 ppm), and Hg (up to 75 ppm). Fluid inclusions in both quartz vein types consist of four phases including L-rich, V-rich, L-V-rich, and L1-L2-V (CO2)-rich phases. Mineralizing hydrothermal fluid is typified by CO2-rich fluid, moderate temperature of 300 - 400 ºC and a typical low salinity (0.36 to 0.54 wt.% NaCl eq). Based on those key features, gold mineraliza­tion in Buru Island meets the characteristics of LS epithermal or orogenic gold deposit types; however, it tends to be fitter with orogenic gold deposit rather than another type.  
Metamorphic Rock-Hosted Orogenic Gold Deposit Type as a Source of Langkowala Placer Gold, Bombana, Southeast Sulawesi Idrus, Arifudin; Nur, I.; Warmada, I. W.; Fadlin, Fadlin
Indonesian Journal on Geoscience Vol 6, No 1 (2011)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2637.886 KB) | DOI: 10.17014/ijog.v6i1.114

Abstract

DOI: 10.17014/ijog.v6i1.114In 2008, placer gold was discovered in Langkowala area (Bombana Regency), Southeast Sulawesi, Indonesia, and more than 60,000 traditional gold miners in the early 2009 have been operating by digging vertical pits and panning active stream sediments. The grade of placer gold ranges from 50 to 140 g/t. Local geological framework indicates that the placer gold is not related to volcanic rock-related hydrothermal gold deposit, e.g. epithermal, skarn or porphyry. This paper describes a preliminary study on possible primary deposit type as a source of the Langkowala (Bombana) secondary placer gold. A field study indicates that the Langkowala (Bombana) placer/paleoplacer gold is possibly related to gold-bearing quartz veins/veinlets hosted by metamorphic rocks particularly mica schist and metasediments in the area. These quartz veins/veinlets are currently recognized in metamorphic rocks at Wumbubangka Mountains, a northern flank of Rumbia Mountain Range. Sheared, segmented quartz veins/veinlets are of 2 cm to 2 m in width and contain gold in a grade varying between 2 and 61 g/t. At least, there are two generations of the quartz veins. The first generation of quartz vein is parallel to foliation of mica schist and metasediments with general orientation of N 300oE/60o; the second quartz vein generation crosscut the first quartz vein and the foliation of the wallrock. The first quartz veins are mostly sheared/deformed, brecciated, and occasionally sigmoidal, whereas the second quartz veins are relatively massive. The similar quartz veins/veinlets types are also probably present in Mendoke Mountain Range, in the northern side of Langkowala area. This primary gold deposit is called as ‘orogenic gold type’. The orogenic gold deposit could be a new target of gold exploration in Indonesia in the future.
Geology and Characteristics of Pb-Zn-Cu-Ag Skarn Deposit at Ruwai, Lamandau Regency, Central Kalimantan Idrus, Arifudin; Setijadji, L. D.; Thamba, F.
Indonesian Journal on Geoscience Vol 6, No 4 (2011)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (658.914 KB) | DOI: 10.17014/ijog.v6i4.126

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DOI: 10.17014/ijog.v6i4.126This study is dealing with geology and characteristics of mineralogy, geochemistry, and physicochemical conditions of hydrothermal fluid responsible for the formation of skarn Pb-Zn-Cu-Ag deposit at Ruwai, Lamandau Regency, Central Kalimantan. The formation of Ruwai skarn is genetically associated with calcareous rocks consisting of limestone and siltstone (derived from marl?) controlled by NNE-SSW-trending strike slip faults. It is localized along N 70° E-trending thrust fault, which also acts as the contact zone between sedimentary and volcanic rocks in the area. The Ruwai skarn is mineralogically characterized by prograde alteration comprising garnet (andradite) and clino-pyroxene (wollastonite), and retrograde alteration composed of epidote, chlorite, calcite, and sericite. Ore mineralization is typified by sphalerite, galena, and chalcopyrite, formed at early retrograde stage. Galena is typically enriched in silver up to 0.45 wt % and bismuth of about 1 wt %. No Ag-sulphides are identified within the ore body. Geochemically, SiO is enriched and CaO is depleted in limestone, consistent with silicic alteration (quartz and calc-silicate) and decarbonatization of the wallrock. The measured resources of the deposit are 2,297,185 tonnes at average grades of 14.98 % Zn, 6.44% Pb, 2.49 % Cu, and 370.87 g/t Ag. Ruwai skarn orebody was originated at moderate temperatures of 250 - 266 °C and low salinity of 0.3 - 0.5 wt.% NaCl eq. The late retrograde stage was formed at low temperature of 190 - 220 °C and low salinity of ~0.35 wt.% NaCl eq., which was influenced by meteoric water incursion at the late stage of the Ruwai Pb-Zn-Cu-Ag skarn formation.
Thermal and Infrared Studies of Garnierite from the Soroako Nickeliferous Laterite Deposit, Sulawesi, Indonesia Sufriadin, Sufriadin; Idrus, Arifudin; Pramumijoyo, S.; Warmada, I. W.; Nur, I.; Imai, A.; Imran, A. M.; Kaharuddin, Kaharuddin
Indonesian Journal on Geoscience Vol 7, No 2 (2012)
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3347.354 KB) | DOI: 10.17014/ijog.v7i2.137

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DOI: 10.17014/ijog.v7i2.137Mineralogical characterization of some garnierite samples from Soroako have been conducted using X-ray diffraction, thermal analysis, and infrared spectroscopy methods. XRD patterns reveal the samples mainly containing the mixture of kerolite (talc-like phase) and serpentine with minor smectite, sepiolite, and silica. Thermal analyses of garnierite samples indicated by DTA curves are in good agreement with patterns that have been reported in literature. Three endothermic peaks normally occur in the ranges between 58º C and <800º C illustrating three steps of weight losses: adsorbed, bound, and hydroxyl/crystal water. One additional weight loss in low temperature region of sepiolite is corresponding to the lost of zeolitic water. Infrared spectra appeared in 3800 - 3200 cm-1 region generally exhibit broad absorption bands, indicating low crystallinities of studied samples and can be assigned to the presence of hydroxyl group bonded to octahedral coordination mainly Mg atom. The bands observed at 1660 cm-1, 1639 cm-1, 1637 cm-1, and 1633 cm-1 in all samples indicate water molecules. FTIR spectra displaying the strong bands at 1045 cm-1, 1038 cm-1, and 1036 cm-1 could be related to the presence of Si-O-Si bonds linking to tetrahedral coordination. The strong absorption bands appeared at 511 cm-1, 505 cm-1, 499 cm-1, and 496 cm-1 in respective samples are attributed to divalent cation bonds (e.g. Mg, Ni-O). Both TG/DTA and FTIR seem to be the powerful tool in diagnosing the crystal chemistry of garnierite which is mainly composed of phyllosilicate minerals.
Utilizing coal remaining resources and post-mining land use planning based on GIS-based optimization method : study case at PT Adaro coal mine in South Kalimantan Anis, Mohamad; Idrus, Arifudin; Amijaya, Hendra; Subagyo, Subagyo
Journal of Geoscience, Engineering, Environment, and Technology Vol 2 No 2 (2017): JGEET Vol 02 No 02 : June (2017)
Publisher : UIR PRESS

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1005.962 KB) | DOI: 10.24273/jgeet.2017.2.2.307

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Coal mining activities may cause a series of environmental and socio-economic issues in communities around the mining area. Mining can become an obstacle to environmental sustainability and a major hidden danger to the security of the local ecology. Therefore, the coal mining industry should follow some specific principles and factors in achieving sustainable development. These factors include geological conditions, land use, mining technology, environmental sustainability policies and government regulations, socio-economic factors, as well as sustainability optimization for post-mining land use. Resources of the remains of the coal which is defined as the last remaining condition of the resources and reserves of coal when the coal companies have already completed the life of the mine or the expiration of the licensing contract (in accordance with government permission). This research uses approch of knowledge-driven GIS based methods mainly Analytical Hierarchy Process (AHP) and Fuzzy logic for utilizing coal remaining resources and post-mining land use planning. The mining area selected for this study belongs to a PKP2B (Work Agreement for Coal Mining) company named Adaro Indonesia (PT Adaro). The result shows that geologically the existing formation is dominated by Coal Bearing Formation (Warukin Formation) which allows the presence of remains coal resource potential after the lifetime of mine, and the suitability of rubber plantation for the optimization of land use in all mining sites and also in some disposal places in conservation areas and protected forests.
Metamorphic rock-hosted orogenic gold deposit style at Bombana (Southeast Sulawesi) and Buru Island (Maluku): Their key features and significances for gold exploration in Eastern Indonesia Idrus, Arifudin; Prihatmoko, Sukamandaru; Harjanto, Ernowo; Meyer, Franz Michael; Nur, Irzal; Widodo, Wahyu; Agung, Lia Novelia
Journal of Geoscience, Engineering, Environment, and Technology Vol 2 No 2 (2017): JGEET Vol 02 No 02 : June (2017)
Publisher : UIR PRESS

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1215.235 KB) | DOI: 10.24273/jgeet.2017.2.2.291

Abstract

In Indonesia, gold is commonly mined from epithermal-, porphyry-, and skarn-type deposits that are commonly found in volcanic belts along island arcs or active continental margin settings. Numerous gold prospects, however, were recently discovered in association with metamorphic rocks. This paper focuses on metamorphic rock-hosted gold mineralization in Eastern Indonesia, in particular the Bombana (SE Sulawesi) and Buru Island (Maluku) prospects. At Bombana, gold-bearing quartz-veins are hosted by the Pompangeo metamorphic complex. Sheared, segmented veins vary in thickness from 2 cm to 2 m. Gold is mainly present in the form of ‘free gold’ among silicate minerals and closely related to cinnabar, stibnite, tripuhyite, and in places, minor arsenopyrite. The gold distribution is erratic, however, ranging from below detection limit up to 134 g/t. At least three generations of veins are identified. The first is parallel to the foliation, the second crosscuts the first generation of veins as well as the foliation, and the late-stage laminated deformed quartz-calcite vein represents the third mineralization stage. The early veins are mostly massive to crystalline, occasionally brecciated, and sigmoidal, whereas the second-stage veins are narrower than the first ones and less subjected to brecciation. Gold grades in the second- and third-stage veins are on average higher than that in the earlier veins. Microthermometric and Raman spectrometric studies of fluid inclusions indicate abundant H2O-NaCl and minor H2O-NaCl-CO2 fluids. Homogenization temperatures and salinities vary from 114 to 283 ºC and 0.35 to 9.08 wt.% NaCl eq., respectively. Crush-leach analysis of fluid inclusions suggests that the halogen fluid chemistry is not identical to sea water, magmatic or epithermal related fluids, but tends to be similar to fluids in mesothermal-type gold deposits. In Buru Island (Gunung Botak and Gogorea prospects), two distinct generations of quartz veins are identified. Early quartz veins are segmented, sigmoidal discontinuous and parallel to the foliation of the host rock. This generation of quartz veins is characterized by crystalline relatively clear quartz, and weakly mineralized with low sulfide and gold contents. The second type of quartz veins occurs within the ‘mineralized zone’ of about 100 m in width and ~1,000 m in length. Gold mineralization is intensely overprinted by argillic alteration. The mineralization-alteration zone is probably parallel to the mica schist foliation and strongly controlled by N-S or NE-SW-trending structures. Gold-bearing quartz veins are characterized by banded texture particularly following host rock foliation and sulphide banding, brecciated and rare bladed-like texture. Alteration types consist of propylitic (chlorite, calcite, sericite), argillic and carbonation represented by graphite banding and carbon flakes. Ore mineral comprises pyrite, native gold, pyrrhotite, and arsenopyrite. Cinnabar and stibnite are present in association with gold. Ore chemistry indicates that 11 out of 15 samples yielded more than 1 g/t Au, in which 6 of them graded in excess of 3 g/t Au. All high-grade samples are composed of limonite or partly contain limonitic material. This suggests the process of supergene enrichment. Interestingly, most of the high-grade samples contain also high concentrations of As (up to 991ppm), Sb (up to 885ppm), and Hg (up to 75ppm). Fluid inclusions in both quartz vein types consist of 4 phases including L-rich, V-rich, L-V-rich and L1-L2-V (CO2)-rich phases. The mineralizing hydrothermal fluid typically is CO2-rich, of moderate temperature (300-400 ºC), and low salinity (0.36 to 0.54 wt.% NaCl eq). Based on those key features, gold mineralization in Bombana and Buru Island tends to meet the characteristics of orogenic, mesothermal types of gold deposit. Metamorphic rock-hosted gold deposits could represent the new targets for gold exploration particularly in Eastern Indonesia.
Hydrothermal Alteration And Vein Types Of The Randu Kuning Porphyry Cu-Au Deposit At Selogiri Area, Wonogiri Sutarto, Sutarto; Idrus, Arifudin; Putranto, Sapto; Harjoko, Agung; Setijadji, Lucas D; Meyer, Franz M; Danny, Rama
Buletin Sumber Daya Geologi Vol 9, No 1 (2014): Buletin Sumber Daya Geologi
Publisher : Buletin Sumber Daya Geologi

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Abstract

Many Tertiary hydrothermal altered dioritic composition intrusive rocks were found at the Randu Kuning  area and its vicinity, Selogiri, including hornblende microdiorite, hornblende-pyroxene diorite and quartz diorite. The hydrothermal fluids which responsible for the alteration and mineralization at the area is associated with the occurence of the horblende microdiorite intrusion.The alteration zone at the Randu Kuning area and its vicinity can be divided into several hydrothermal alteration zones, such as potassic (magnetite-biotite-K feldspar), prophyllitic (chlorite-magnetite-epidote-carbonate), phyllic (quartz-sericite-chlorite) and argillic (clay mineral-sericite). The alteration pattern in the Randu Kuning porphyry Cu-Au deposit is tipically a diorite  model characterising by the domination of  potassic alteration and prophyllitic zone. Phyllic and argillic alteration types are  restrictive found within the fault zones.A lot of porphyry vein types were found and observed at the Randu Kuning area, and classified into at least seven  vein types.  The paragenetic sequence of those veins from the earliest to the latest respectively are 1). Magnetite-chalcopyrite±quartz-biotite veinlets, 2). Quartz±magnetite (A type) veins, 3). Banded/Laminated quartz-magnetite (M type) veins, 4). Quartz±K feldspar (B type)veins, 5). Quartz  with thin centre line sulphide (AB type) veins, 6). Pyrite±chalcopyrite (C type) veinlets, and 7). Pyrite-quartz+chalcopyrire+carbonate (Dtype) veins. Gold and copper mineralisation  of the Randu Kuning Porphyry Cu-Au deposit, mostly related to the presence of quartz veins/veinlets containing sulfide i.e. Quartz  with thin centre line sulphide veins, Pyrite±chalcopyrite veinlets, and Pyrite-quartz+chalcopyrire+ carbonate veins.
THE METAMORPHIC ROCK-HOSTED GOLD MINERALIZATION AT BOMBANA, SOUTHEAST SULAWESI: A NEW EXPLORATION TARGET IN INDONESIA Idrus, Arifudin; Fadlin, Fadlin; Prihatmoko, Sukmandaru; Warmada, I Wayan; Nur, Irzal; Meyer, Franz Michael
Jurnal Geologi dan Sumberdaya Mineral Vol 22, No 1 (2012): Jurnal Sumber Daya Geologi
Publisher : Pusat Survei Geologi

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Abstract

Placer gold has been discovered in Bombana, SE-Sulawesi, Indonesia. The placer gold is not associated with volcanic rock-related gold deposits. This paper discusses the primary gold mineralization as the source of the placer gold. The placer gold is possibly derived from gold-bearing quartz veins hosted by Pompangeo Metamorphic Complex (PMC). Pyrite, chalcopyrite, cinnabar, stibnite and tripuhyite are present. Sheared, segmented vein varies in thickness from 2 cm to 2 m. The veins contain erratic gold in various grades from below detection limit (0.005 g/t) to 134 g/t. At least three generations of veins are identified. The first is parallel to the foliations, the second crosscuts the first generation of veins/foliations, and the third is of laminated deformed quartz+calcite veins at the late stage. The first veins are mostly massive to crystalline, occasionally brecciated and sigmoidal, whereas the second veins are narrower than the first and relatively brecciated. Gold grades in the second and third veins are relatively higher than that in first veins. Fluid inclusion study of quartz veins indicates abundant H2O-NaCl and a small amount of H2O-NaCl-CO2 inclusions. Temperature of homogenization (Th) and salinity of the first vein vary from 184.7 to 245.3 ºC and 5.26 to 9.08 wt.% NaCl eq., respectively. The second generation vein was originated at Th of 132.1-283.4 ºC and salinity of 3.55-5.86 wt.%NaCl eq., whereas the third generation vein formed at lowest Th varying from 114 to 176ºC and less saline fluid at salinity range between 0.35 and 4.03 wt.% NaCl eq. Gold is mainly identified in the form of 'free gold' among silicate minerals. Mineralogically, gold is closely related to cinnabar, stibnite, tripuhyite and possibly minor arsenopyrite. Metamorphogenic gold deposits would be the new target of gold exploration in Indonesia.Keyword: Gold mineralization, orogenic-type, Bombana, Southeast Sulawesi, Indonesia
Eksplorasi Endapan Hidrotermal di daerah Kasihan, Pacitan, Jawa Timur Asrafil, Asrafil; Idrus, Arifudin; Wintolo, Djoko
Jurnal Geologi dan Sumberdaya Mineral Vol 18, No 4 (2017): Jurnal Geologi dan Sumberdaya Mineral
Publisher : Pusat Survei Geologi

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Abstract

This research aims to identify hydrothermal mineral deposits using geomagnetic methods. The geomagnetic method used to obtain anomaly of magnetic field intensity contrast. Furthermore, there is also been conducted taking and analysis samples of rock using petrography, ore microscopic and XRD. It is done to obtain mineralogical characteristics of hydrothermal mineral deposits that becoming the exploration target. The results showed that hydrothermal mineral deposits in research area was characterized by hydrothermal alteration of argillic (kaoline-illite), propylitic (calcite-chlorite) and skarn (quatrz-calcite-pyroxine/ clinopyroxine). Ore minerals are present of sulphide minerals such as pyrite, chalcopyrite, sphalerite, covelit and oxide minerals such as hematite abundance. The existence of hydrothermal mineral deposits are associated with skarn type deposit. Zones of mineral deposits of metallic ores are characterized by a significant contrast magnetic anomalies with high magnetic field intensity higher than 110,31 nT on the total magnetic intensity anomaly and higher than 11,09 nT on the residual magnetic intensity anomaly, as the response from the presence of metal in the ore mineral enrichment of rock material.keywords : hydrothermal minerals, magnetic field anomaly, petrography, ore microscopic, XRD skarn, Kasihan
Co-Authors A. Harijoko A. Harijoko A. Imai A. Imai A. M. Imran Abdul, Abdul Agung Harijoko Ahmad Ahmad Aji Syailendra Ubaidillah Aji Syailendra Ubaidillah Anastasia Dewi Titisari Araki, Naoto Asrafil Asrafil Ati, E. M. Atmoko, Didik Dwi Atmoko, Didik Dwi Bambang Priadi Dana, Cendi D. P. Danny, Rama Didik Dwi Atmoko Didik Dwi Atmoko Djoko Wintolo, Djoko Donatus Hendra Amijaya E. M. Ati E. M. Ati Edy Nursanto Ernowo Ernowo Ernowo Ernowo Ernowo Harjanto Ernowo Harjanto, Ernowo Ernowo, Ernowo F. M. Meyer F. M. Meyer F. Thamba F. Thamba Fadlin Fadlin Fadlin Fadlin Fadlin Fadlin Fadlin Fadlin Fadlin Idrus Fadlin Idrus Fadlin, Fadlin Fadlin, Fadlin Ferian Anggara Franklin Franklin Franklin Franklin Franklin, Franklin Franz Michael Meyer Franz Michael Meyer Franz Michael Meyer, Franz Michael Godang, Shaban Godang, Shaban Hakim, Fahmi Handayani, Esti Harijoko, A. Harjoko, Agung Hasria Hasria Hasria Hasria, Hasria Herfien Samalehu Herfien Samalehu Hill Gendoet Hartono Himawan Tri Bayu Murti Petrus I Gde Sukadana I Wayan Warmada I. Nur I. Nur I. Nur Idrus, Fadlin Imai, A. Imai, Akira Indra Sanjaya Irzal Nur, Irzal Isyqi Isyqi Iwan Setiawan Iwan Setiawan Johan Arif, Johan Kaharuddin Kaharuddin Kaharuddin, Kaharuddin Kant, Win Khant, Win Koichiro Watanabe, Koichiro Kolb, Jochen L. D. Setijadji L. D. Setijadji Lai, Chun-Kit Leeuwen, Theo Van Lia Novelia Agung Lia Novelia Agung, Lia Novelia Lucas Donny Setijadji Mansur, Suaib Meak, Ignas A. Meyer, F. M. Meyer, Franz M Mochammad Aziz Mochammad Aziz, Mochammad Moetamar Moetamar Moetamar Moetamar Moetamar, Moetamar Mohamad Anis Mohamad Anis, Mohamad Mudinillah, Adam Myaing, Yu Yu Nugroho Imam Setiawan Nur, I. Nur, I. Okki Verdiansyah Pramumijoyo, Pranayoga Pramumijoyo, S. Pratomo, Septyo Uji Priadi, Bambang Prihatmoko, Sukmandaru Putranto, Sapto Putranto, Sapto Rahmah, Yuyun Prihatining Rahmayuddin, Rahmayuddin Rika Ernawati Rohaya Langkoke S. Pramumijoyo S. Pramumijoyo Sapto Putranto Setiawan, Iwan Setiawan, Iwan Setijadji, L. D. Setijadji, Lucas D Shaban Godang Shaban Godang Sindern, Sven Siti Rahmawati H. Budiawan Subagyo Pramumijoyo, Subagyo Subagyo Subagyo Subagyo Subagyo Sufriadin, Sufriadin Sukadana, I Gde Sukamandaru Prihatmoko Sukamandaru Prihatmoko, Sukamandaru Sukmandaru Prihatmoko Sukmandaru Prihatmoko Sutarto Sutarto Sutarto Sutarto Sven Sindern Syafruddin Maula Syafruddin Maula Tamba, Fenny Thamba, F. Theo Van Leeuwen Thwee Aye, May Titisari, Anastasia Dewi Tun, Myo Min Wahyu Widodo Wahyu Widodo Waterman Sulistyana Bargawa Yonezu, Kotaro Yu Yu Myaing Yurniadi, Feddy