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"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."

"Kalimantan Tengah merupakan salah satu daerah dengan potensi cadangan pasir silika terbesar di Indonesia. Pasir silika merupakan mineral bukan logam yang dimanfaatkan sebagai material bangunan. Oleh karena itu, potensi persebaran pasir silika di bawah permukaan diidentifikasi menggunakan survei geofisika. Dalam penelitian ini, metode Resistivitas dengan konfigurasi Wenner Alpha dan Ground Penetrating Radar dengan konfigurasi radar reflection profiling merupakan salah dua metode geofisika yang digunakan untuk mengetahui keadaan bawah permukaan. Metode Ground Penetrating Radar digunakan untuk mengkonfirmasi hasil pengolahan data metode resistivitas karena metode resistivitas dilakukan pengukuran di area dengan permukaan pasir silika sehingga menyulitkan injeksi arus ke bawah permukaan. Selain itu, data bor digunakan sebagai data sekunder untuk membantu dalam interpretasi hasil pengolahan data. Hasil pengolahan data adalah penampang 2D metode Resisitivitas yang berisi nilai resistivitas sebenarnya bawah permukaan dan penampang 2D radargram GPR, serta penampang 2D nilai permitivitas relatif GPR. Berdasarkan hasil tersebut, nilai resistivitas pasir silika sebesar > 136 Ωm dan nilai permivitas relatif sebesar 16 - 26. Dari hasil pengolahan dan interpretasi kedua metode, ditemukan persebaran pasir silika pada kedalaman kurang dari 10 m dan lebih dari 30 m.......Central Kalimantan is one of the areas with the largest potential reserves of silica sand in Indonesia. Silica sand is a non-metallic mineral that is used as a building material. Therefore, the potential distribution of silica sand below the surface can be identified using geophysical surveys. In this research, the Resistivity method with a Wenner Alpha configuration and Ground Penetrating Radar with a reflection profiling radar configuration are two geophysical methods used to determine the condition of the subsurface. The Ground Penetrating Radar method was used to confirm the results of the resistivity method data processing because the resistivity method was measured in an area with a silica sand surface, making it difficult to inject current into the subsurface. In addition, drill data is used as secondary data to assist in the interpretation of data processing results. The result of data processing is a 2D cross section of the Resisitivity method which contains the actual resistivity value of the subsurface, 2D cross section of the GPR radargram, and 2D cross section of the GPR relative permittivity value. Based on these results, the resistivity value of silica sand is > 136 Ωm and the relative permittivity value is 16 - 26. From the results of processing and interpretation of the two methods, it was found that the distribution of silica sand was at depths of less than 10 m and more than 30 m."