Hasil Pencarian  ::  Simpan CSV :: Kembali

"Metode Induced Polarization (IP) dapat digunakan untuk memahami karakteristik batuan bawah-permukaan bumi yang mengandung mineral sulfida berdasarkan sifat kelistrikannya (resistivitas dan percent frequency effect). Intensitas ubahan (alterasi) batuan akibat proses hidrothermal dapat digunakan sebagai petunjuk tempat akumulasi mineralisasi sulfida. Pengukuran geolistrik metode IP pada Frequency Domain telah dilakukan di daerah penelitian “A” Banten pada 6 lintasan dengan jarak antar elektrode 25 meter, untuk menentukan zona alterasi dan mineralisasi sulfida. Pemodelan terintegrasi (integrated modelling) secara 2-dimensi data IP yang ditunjang dengan data magnetik dan data geologi telah berhasil memberikan informasi lebih detail akan pola penyebaran urat (vein) kuarsa yang berhubungan dengan pengendapan emas. Dari hasil studi tersebut dapat disimpulkan bahwa penyebaran vein kuarsa diduga terdapat pada Lintasan GKD 1 sampai Lintasan GKD 3 dengan kedalaman maksimum sekitar 50 meter. Untuk memastikan hasil studi geofisika perlu dilakukan pemboran eksplorasi untuk mengetahui kadar kandungan emas.

---

Induced Polarization method can be used for understanding the characteristic of subsurface rock containing sulphide minerals based on its electrical properties (i.e. resistivity and percent frequency effect). Intensity of rock alteration due to hydrothermal process can be utilized for guiding the accumulation of sulphide mineralization. Geoelectrical measurements using IP method with frequency domain have been carried out in study area “A”, Banten along 6 lines with electrode spacing of 25 meter for delineating alteration zones and sulphide mineralization. Integrated two-dimensional modelling of the IP data incorporated with magnetic and geological data has revealed detailed information of the distribution of quartz vein patterns related to gold deposit. Based on the study, it is concluded that the distribution of quartz vein is delineated in the Line GKD 1 to Line GKD 3 with maximum depth of about 50 meter. To confirm the geophysical study, it is necessary to carry out exploration drilling to identify the gold contain."

"Metode utama IP dan resistivitas yang didukung dengan data magnetik dapat mendelineasi zona mineralisasi emas berdasarkan nilai chargeability dan resistivitasnya. Pengukuran metode IP menggunakan domain waktu dan konfigurasi dipole-dipole sebanyak 4 lintasan dengan spasi elektroda 25 m. Pengukuran dilakukan di daerah ‘X’ yang mempunyai kondisi geologi pembentukan mineralisasi emas sistem epitermal sulfida tinggi yang terbentuk dengan kedalaman dangkal 100-500 m. Pengukuran metode IP menggunakan instrumen Supersting R8/IP. Dan dari pengukuran didapatkan data yang berupa chargeability semu dan resistivitas semu yang selanjutnya diinversi menggunakan software Res2Dinv untuk mendapatkan nilai chargeability dan resistivitas yang sebenarnya. Hasil pengolahan data IP ditampilkan secara 2D dengan software Res2Dinv dan visualisasi 3D menggunakan software Geoslicer-X. Dari integrasi data IP, resistivitas dan magnetik didapatkan korelasi hasil berupa 3 zona menarik yang diinterpretasikan sebagai mineralisasi vuggy quartz dengan nilai chargeability > 400 ms yang disertai dengan nilai resistivitas > 800 Ohm.m dan respon profil magnetik yang berundulasi pada lintasan 200. Dan adanya zona lemah berupa patahan terdeteksi dengan nilai chargeability yang rendah yaitu sekitar < 50 ms, nilai resistivitas < 20 Ohm.m dan profil intensitas magnetik yang drop, yang merupakan jalur bagi larutan hidrotermal naik ke permukaan.

---

The main methods of IP and resistivity, supported by magnetic data can delineate zones of gold mineralization based on their chargeability and resistivity values​​. Measurement using time domain IP and dipole-dipole configuration of resistivity along 4 profiles with electrode spacing of 25 m. Measurements were carried out in the area "X" which had gold mineralization geological conditions of formation of high sulphidation epithermal systems formed in shallow depth of 100-500 m. Measurement was done by using instruments Supersting R8/IP IP. The data obtained from measurements in the form of apparent chargeability and apparent resistivity were subsequently inverted using the Res2Dinv software to get the value of the true chargeability and resistivity. IP data processing results displayed in 2D view using Res2Dinv software and 3D visualization using Geoslicer-X software.

From the integration of IP, resistivity and magnetic data correlation, resulted 3 interesting zone interpreted as mineralization of vuggy quartz with chargeability values​​ > 500 ms, resistivity values​​> 600 Ohm.m and undulated magnetic’s response curve along the profile 200. The existence of zone in form of the fault was detected as a low chargeability, at values ​ about < 50 ms, low resistivity at value about < 50 Ohm.m and dropped magnetic intensity profiles, which is interpreted as the pathway for hydrothermal solutions up to the surface."

"Komoditas emas yang tinggi serta lapangan poduksi Pongkor yang sudah beroperasi sejak puluhan tahun lalu membuat perlu ditemukannya zona potensi baru untuk produksi pertambangan emas. Untuk mengetahui zona mineralisasi emas dan kemenerusannya, maka dilakukan studi geofisika dengan menggunakan metode Time Domain Induced Polarization (TDIP) dan magnetik. Data TDIP yang terdiri dari data resistivitas dan chargeabilitas diinterpretasi untuk menentukan zona alterasi dan mineralisasi bawah permukaan yang dikorelasi dengan data magnetik yang telah di inversi 3D sehingga mendapatkan parameter suseptibilitas. Berdasarkan nilai resistivitas di daerah penelitian, zona alterasi argilik diduga memiliki nilai <50 Ohm.m dan zona alterasi silisifikasi diduga memiliki nilai >50 Ohm.m. Nilai chargeabilitas zona mineralisasi diindikasikan memiliki nilai 100-810 m.sec. Zona mineralisasi di daerah penelitian memiliki nilai suseptibilitas berkisar antara -0.073 hingga -0.021 cgs. Dari ketiga parameter tersebut, diduga zona mineralisasi terdapat di bagian Timur daerah penelitian dan berorientasi Utara-Selatan searah dengan orientasi sesar utama.

---

The high gold commodity as well as the Pongkor production field that has existed since last year made it necessary to find a new potential zone for gold mining production. To find out the zone of gold mineralization and its continuity, then conducted geophysical studies by using the methods of Time-Domain Induced Polarization (TDIP) and magnetic. TDIP data consisting of resistivity and chargeability data are interpreted to determine alteration zones and subsurface mineralization that are correlated with magnetic data that has been inversed in 3D to obtain susceptibility parameters.

Based on the value of resistivity in the area of research, the argilic alteration zones are thought to has a value of < 50 Ohm. Silisification alteration zones supposedly has the value > 50 Ohm. m. The value of the chargeability zone of mineralized indicated has a value of 100-810 m sec. Research in the area of mineralized zone have a value in the range suseptibilitas -0073 to -0.021 cgs. From those parameter of the mineralized zone, it is assumed that the mineralization zone is in the eastern part of the study area and oriented North-South direction with the orientation of the main fault."

"Indonesia terletak pada pertemuan tiga lempeng yang menyebabkan munculnya jajaran busur magmatik. Pada jajaran busur magmatik terjadi pengendapan mineral emas. Endapan emas yang berada di Indonesia didominasi dengan endapan epithermal sulfidasi rendah. Untuk menemukan cadangan dan potensi endapan mineralisasi emas dibutuhkan analisis untuk mengetahui lokasi dan bentuk geometri dari zona endapan mineralisasi emas. Metode geofisika merupakan metode yang dapat menganalisisi zona endapan mineralisasi emas. Metode geofisika yang digunakan dalam penelitian ini adalah metode resistivity dan induced polarization dengan konfigurasi dipole-dipole. Metode resistivity digunakan untuk mengidentifikasi jenis batuan yang berada diwilayah penelitian. Sedangkan metode induced polarization digunakan untuk mengidentifikasi lokasi dan volume zona pengendapan mineralisasi emas. Jumlah lintasan yang digunakan sebanyak 3 lintasan dengan masing masing lintasan memiliki panjang 405 m dengan 81 elektoda. Hasil data pengukuran metode resistivity dan induced polarization diinversi menggunakan software res2dinv dan dilakukan least square inversion untuk memperoleh penampang 2D. Hasil pengolahan data menunjukan variasi resistivity berkisar 4,5419-2787,6 Ωm dan induced polarization berkisar 36,720-833,92 msec. Berdasarkan korelasi penampang 2D dan peta geologi ditemukan bahwa sebaran jenis batuan wilayah penelitian adalah breksi tuff dengan kisaran nilai resistivity 70,557-1313,7Ωm dan andesit dengan kisaran nilai 595,8-1313,7 Ωm. Zona mineralisasi emas dengan nilai induced polarization ≥200 msec. Berdasarkan korelasi penampang 2D resistivity dan induced polarization ditemukan bahwa pengendapan mineralisasi emas berada pada breksi tuff dan andesit. Dari penampang 2D dilakukan pemodelan 3D untuk mengetahui estimasi volume zona mineralisasi emas software. Ditemukan hasil volume zona mineralisasi emas sebesar 289.452,6103 .

---

Indonesia is situated at the confluence of three tectonic plates, which gives rise to the emergence of a magmatic arc range. In the magmatic arc sequence, gold mineral deposition occurs. Gold deposits in Indonesia are dominated by low sulphidation epithermal deposits. In order to identify reserves and potential gold mineralization deposits, it is necessary to conduct an analysis to determine the location and geometry of the gold mineralization deposit zone. Geophysical methods are a type of analysis that can be used to analyse gold mineralization deposit zones. The geophysical methods employed in this research include resistivity and induced polarization methods with a dipole-dipole configuration. The resistivity method is utilized to identify the type of rock present in the research area, while the induced polarization method is employed to ascertain the location and volume of gold mineralization deposition zones. The number of tracks utilized was three, with each track measuring 405 m and comprising 81 electrodes. The measurement data obtained from the resistivity and induced polarization methods were inverted using the res2dinv software, and least square inversion was performed to obtain two-dimensional cross sections. The results of data processing indicate that the resistivity variation ranges from 4.5419 to 2787.6 Ωm, while the induced polarization ranges from 36.720 to 833.92 msec. Correlation of the 2D cross sections with geological maps revealed that the rock types present in the study area are tuff breccia and andesite, with resistivity values ranging from 70.557 to 1313.7 Ωm. Gold mineralization zones with induced polarization values ≥200 msec. Based on the correlation of 2D resistivity and induced polarization cross sections, it was determined that gold mineralization deposition occurred in tuff breccia and andesite. From the 2D cross section, 3D modelling was conducted to estimate the volume of the gold mineralization zone. The volume of the gold mineralization zone was determined to be 289,452.6103 m3."

"Indonesia terletak pada pertemuan tiga lempeng litosfer yang menyebabkan munculnya jajaran busur magmatik. Busur magmatik tersebut membuat Indonesia kaya akan potensi mineral, seperti mineral emas. Salah satu busur magmatik yang melintasi Indonesia berada pada wilayah pulau Jawa adalah busur Sunda-Banda. Busur tersebut mempunyai potensi mineral bijih tipe endapan epitermal. Oleh karena itu, perlu dilakukan survei geofisika agar dapat mengetahui zona mineralisasi emas. Zona mineralisasi emas tersebut diidentifikasi menggunakan metode resistivitas dan induced polarization konfigurasi Dipole-Dipole dengan menggunakan 81 elektroda dan jarak spasi 5m. Proses akuisisi data dilakukan sebanyak 3 lintasan, yaitu lintasan BDG-02, BDG-03, dan BDG-04 dengan orientasi dari arah Utara ke Selatan. Pemodelan 2D dilakukan dengan menggunakan software 2D untuk memperoleh penampang dengan nilai resistivitas dan chargeability yang sebenarnya. Selanjutnya dilakukan pengolahan pemodelan 3D menggunakan software 3D untuk mengidentifikasi kemenerusan zona mineralisasi emas. Pada daerah penelitian nilai resistivitas dan chargeability memiliki rentang nilai berkisar antara 1 – 6787 Ωm dan 0 – 888 msec. Zona mineralisasi emas di daerah penelitian memiliki nilai resistivitas 3 – 1483 Ωm dan nilai chargeability ≥164 msec. Korelasi penampang 2D resistivitas dan induced polarization ditemukan bahwa pengendapan mineralisasi emas berada pada batuan breksti tuf dan andesit. Berdasarkan hasil penampang 3D, kemenerusan zona mineralisasi emas terdapat pada lintasan BDG-03 dan BDG-04 di kedalaman ±25m yang berarah Barat Daya-Timur Laut, sedangkan pada lintasan BDG02 zona mineralisasi emas tidak berkelanjutan melainkan berbentuk spot yang berada di kedalaman ±70m. Zona mineralisasi pada setiap lintasan diperkirakan dikontrol oleh struktur yang berorientasi Barat Daya-Timur Laut.

---

Indonesia is located at the confluence of three lithospheric plates that cause the emergence of a series of magmatic arcs. These magmatic arcs make Indonesia rich in mineral potential, such as gold minerals. One of the magmatic arcs that crosses Indonesia in the Java island region is the Sunda-Banda arc. The arc has the potential for epithermal deposit-type ore minerals. Therefore, it is necessary to conduct a geophysical survey in order to determine the gold mineralization zone. The gold mineralization zone was identified using the resistivity method and induced polarization Dipole-Dipole configuration using 81 electrodes and 5m spacing. The data acquisition process was carried out as many as 3 passes, namely the BDG-02, BDG-03, and BDG-04 passes with orientation from north to south. 2D modeling was carried out using 2D software to obtain cross sections with actual resistivity and chargeability values. Furthermore, 3D modeling processing was carried out using 3D software to identify the continuity of the gold mineralization zone. In the study area the resistivity and chargeability values have a range of values ranging from 1 - 6787 Ωm and 0 - 888 msec. The gold mineralization zone in the study area has a resistivity value of 3 - 1483 Ωm and a chargeability value of ≥164 msec. The correlation of 2D resistivity and induced polarization cross sections found that the deposition of gold mineralization is in tuff and andesite breccia rocks. Based on the 3D cross-section results, the continuity of the gold mineralization zone is found in the BDG-03 and BDG-04 trajectories at a depth of ±25m in the Southwest-Northeast direction, while in the BDG-02 trajectory the gold mineralization zone is not continuous but in the form of a spot located at a depth of ±70m. The mineralized zones on each traverse are thought to be controlled by a Southwest-Northeast oriented structure."

"Proses magmatisme berkaitan dengan jalur tektonik ring of fire, yang menyebabkan proses mineralisasi hidrotermal sehingga membentuk potensi sumber daya mineral di Indonesia. Salah satu endapan hidrotermal yaitu endapan epitermal sulfidasi rendah yang berada di Lapangan “RD”, Cibaliung. Struktur patahan menjadi pengontrol sistem epithermal sulfidasi rendah sebagai tempat terendapkannya mineral emas. Integrasi data geologi dengan geofisika diperlukan dalam menentukan struktur pengontrol dan zona potensi mineralisasi. Mineral bijih sulfida dapat dibedakan dari sifat kemagnetan dan kelistrikan dikarenakan mineral logam memiliki respon suseptibilitas, resistivitas dan chargeabilitas lebih tinggi dibandingkan dengan mineral non-logam. Zona potensi mineralisasi emas sulfidasi rendah berada pada zona struktur yang didominasi alterasi argilik dan kaya akan mineral sulfida pada alterasi argilik ilitik dengan nilai suseptibilitas menengah hingga tinggi kisaran -83.7 nT – 92.3 nT, resistivitas dengan nilai rendah hingga menengah 0 – 25 ohm.m dan chargeabilitas dengan nilai menengah hingga tinggi 15 - >75 msec. Dari ketiga parameter tersebut, diduga zona mineralisasi berada pada zona struktur patahan berorientasi Baratlaut-Tenggara. Struktur pengontrol zona potensi mineralisasi tersebut berada di lintasan 3 yaitu patahan D dip 62° ke arah NE dan patahan E dip 83° ke arah NE. Lintasan 4 yaitu patahan D dip 79° ke arah NE, patahan E dip 77° ke arah NE dan patahan F dip 73° ke arah NE. Lintasan 7 yaitu patahan D dip 80° ke arah SW dan patahan E dip 75° ke arah NE. Lintasan 8 yaitu patahan D dip 84° ke arah NE dan patahan E dip 66° ke arah NE. Lintasan 9 yaitu patahan A dip 70° ke arah SW dan patahan B dip 81° ke arah NE.

---

The magmatism process is related to the Ring of Fire tectonic pathway, which causes a hydrothermal mineralization process to form potential mineral resources in Indonesia. One of the hydrothermal deposits is an epithermal low-sulfidation deposit in the "RD" Field, Cibaliung. The fault structure controls the epithermal low-sulfidation system as a place for gold mineral deposition. Integration of geological data with geophysical data is required in determining the controlling structure and potential mineralization zone. Sulfide ore minerals can be distinguished from their magnetic and electrical properties because metal minerals have a higher susceptibility, resistivity and chargeability response compared to non-metallic minerals. The potential zone of low sulfidation gold mineralization is located in the structure zone which is dominated by argillic alteration and rich in sulphide minerals in Illitic argillic alteration has medium to high susceptibility values ranging from -83.7 nT - 92.3 nT, resistivity with low to medium values 0 - 25 ohm.m and chargeability with medium to high values of 15 -> 75 msec. From those three parameters, it is assumed that the mineralization zone is located in the NW-SE oriented fault structure zone. The controlling structure for the zone of mineralization potential is in line 3 is fault D with dip 62° to the NE and the E fault with dip 83° to the NE. Line 4 is fault D with dip 79° to the NE, fault E with dip 77° to the NE and fault F with dip 73° to the NE. Line 7, is fault D with dip 80 ° to the SW and the E fault dip 75° to the NE. Line 8 is fault D with dip 84° to the NE and fault E with dip 66 ° to the NE. Line 9 is fault A with dip 70° SW and fault B with dip 81° to NE."

"Penelitian ini dilakukan di lapangan GB untuk mendeteksi keberadaan mineral emas dengan metode Induced Polarization IP . Berdasarkan geologi, terdapat adanya sistem epitermal sulfidasi tinggi di wilayah ini. Hal ini ditandai dengan munculnya keberadaan mineral-mineral logam seperti Au, Cu, dan konsentrasi yang cenderung asam di permukaannya. Mineral emas sendiri merupakan mineral yang bersifat diamagnetik, lunak, dan berasosiasi dengan mineral sulfida. Emas terbentuk akibat dari adanya proses magmatisme atau pengkonsentrasian di permukaan. Mineral emas terangkut oleh fluida hidrotermal ke permukaan dan terbentuk dalam lingkungan hidrotermal dimana ia terbawa ke permukaan bersama dengan senyawa-senyawa yang berikatan dengannya. Metode IP memanfaatkan beda potensial sebagai parameter dalam melakukan pengukuran untuk mendeteksi keberadaan mineral-mineral konduktif di bawah permukaan tanah. Kelebihan metode IP dibanding metode lain adalah kemampuannya mendeteksi mineral logam yang tersebar. Pada penelitian ini digunakan dari 6 data line IP yang dibentangkan ke arah Barat ndash; Timur serta didukung oleh data magnetik. Data diolah dengan inversi 2D dan dimodelkan secara 3D dengan membentangkan hasil secara paralel. Hasilnya, nilai chargeability tertinggi bernilai > 200 ms pada kedalaman 400 meter. Hal ini didukung dengan nilai resistivity yang mencapai > 1000 ohm-meter. Dari data magnetik, nilai magnetik berkisar antara -199.3 nT sampai 244 nT.

---

This research was conducted in field GB to identify the presence of gold minerals by Induced Polarization IP method. Based on geology, there is a high sulfidation epithermal system in the region. This can be determined by the presence of metal minerals such as Au, Cu, and acid concentrations on the surface. Gold is a typical of mineral that is diamagnetic, pliable, and associated with sulphide minerals. It is formed as a result of the process of magmatism or metasomatism on the surface. The hydrothermal fluid content transports gold to the surface along with the other elements associated to it and is formed in hydrothermal environment. The IP method utilizes a potential difference as a parameter in performing measurements to detect the presence of underground conductive minerals. The advantage of IP methods compared to other methods is its ability to detect disseminated conductive minerals. This research use 6 line datas of IP which is extended to West ndash East and supported by magnetic data. Data is processed with 2D inversion and modeled in 3D by spreading results in parallel. As a result, the highest value of chargeability is 200 ms at a depth of 400 meters. This is supported by a resistivity value of 1000 ohm meter. From magnetic data, magnetic values range from 199.3 nT to 244 nT."