Aplikasi Transformasi Reduction to Pole (RTP) Menggunakan Matlab dalam Pengolahan Data Magnetik WDMAM pada Wilayah Tapal Kuda -Jawa Timur

Dalam metode magnetik, medan magnet anomali disebabkan oleh sumber medan magnet dipol. Setiap tempat memiliki sudut iklinasi dan deklinasi magnetik yang berbeda sehingga menyebabkan peta anomali magnetik bersifat kompleks dan interpretasinya menjadi relatif sulit. Untuk mengatasi kerumitan dalam interpretasi data magnetik, penggunaan transformasi reduksi ke kutub RTP sangat penting dilakukan. Tapis RTP dengan memanfaatkan fungsi-fungsi built in Matlab telah berhasil direalisasikan dan diaplikasikan pada data magnetik WDMAM wilayah Tapal Kuda-Jawa Timur. Nilai sudut inklinasi I = -32.82° dan sudut deklinasi D = 0.72° digunakan pada aplikasi RTP daerah ini. Anomali magnetik hasil RTP menunjukkan bahwa terjadi perubahan rentang nilai medan magnet yaitu dari -345.51 nT  s.d 282.30 nT menjadi -975.37 nT s.d 782.38 nT. Selain itu, terjadi pergeseran lokasi klosur anomali magnetik positif dan negatif. Anomali magnetik positif mendominasi di bagian tengah sampai utara Wilayah Tapal Kuda dan diduga berkaitan dengan Zona Vulkanik Kuarter. Klosur-klosur anomali positif mengalami pergeseran letak ke barat di sekitar Gunung Bromo dan Gunung Argopuro. Anomali magnetik negatif mendominasi tepi selatan  Wilayah Tapal Kuda dan diduga berkaitan dengan Zona Pegunungan Selatan. Klosur anomali negatif juga mengalami pergeseran letak yaitu ke barat daya mendekati gunung Semeru

Development LVG GLS Geolectrical Instrument for Monitoring Near Surface Geohazard

This paper was presented in The 3rd Padjadjaran International Physics Symposium 2017, Holiday-Inn Hotel, Bandung , 14-15 November 2017, Department of Physics Universitas Padjadjaran. Authors: Prihadi Sumintadireja1, Ihsan Imaduddin2,4, Wahyu Srigutomo2, Enjang Jaenal Mustopa2, Diky Irawan3, Ihsanuddin A. Lubis3. Abstract: This paper demonstrated a new geolectrical equipment of LVG GLS multi channel , which as part of Laboratory of Application and Geosciences Modeling research, which funded by Institut Teknologi Bandung. Initially, the LVG GLS equipment is designed for delineating geothermal area by mise a la masse configuration. Furthermore, the application is plan to modify for geohazard study, since many landslide occurrence without clear explanation about the involving process due to lack data measurement. The ability of equipment is able to measure resistivity of subsurface condition in real time and continuous. Therefore, spatial and temporal data for monitoring vulnerable landslide area, which identified by geological mapping can be visualized to mitigate the geohazard area more precisely. The simultaneous 80 channel electrode measurement can reduced inhomogeneity of spontaneous potential value, which change by time interval

Application of Magnetotelluric Method to Takigami Geothermal Field in Kyushu, Japan

The Takigami geothermal area is located in the Hohi geothermal region, northeastern Kyushu Island, Japan. This paper demonstrates the application of magnetotelluric (MT) method for geothermal investigation in the Takigami area to determine the subsurfac

Application of Magnetotelluric Method to Takigami Geothermal Field in Kyushu, Japan

The Takigami geothermal area is located in the Hohi geothermal region, northeastern Kyushu Island, Japan. This paper demonstrates the application of magnetotelluric (MT) method for geothermal investigation in the Takigami area to determine the subsurfac

Resistivity Imaging by CSAMT Method in Takigami Geothermal Field in Kyushu, Japan

Controlled-source audiofrequency magnetotelluric (CSAMT) survey was carried out in Takigami geothermal field. Stations were taken closely with regular grid spacing of 150 m. The purpose of the measurements is to delineate a detailed resistivity structur

Resistivity Imaging by CSAMT Method in Takigami Geothermal Field in Kyushu, Japan

Controlled-source audiofrequency magnetotelluric (CSAMT) survey was carried out in Takigami geothermal field. Stations were taken closely with regular grid spacing of 150 m. The purpose of the measurements is to delineate a detailed resistivity structur

Resistivity and Density Structure of Limboto Lake—Pentadio, Gorontalo, Indonesia Based on Magnetotelluric and Gravity Data

Limboto Lake—Pentadio area is located in the province of Gorontalo on the northern arm of Sulawesi Island, Indonesia, which experienced a tectonic process from the Sula Platform collision in the mid-Miocene. This tectonic process led to the westward subduction of the early Miocene and post-collision rifting and uplifting of the arc and subduction along the North Sulawesi Trench during the Late Miocene to the Quaternary periods. The rifting process of the North Sulawesi arc resulted in the formation of the Gorontalo graben zone in the W–E direction. There are geothermal surface manifestations near Limboto Lake, such as hot spring complexes, with temperatures ranging from 74.8 °C to 78.5 °C. To understand the geological structure and prospective geothermal characteristics beneath the investigated area, we performed integrated magnetotelluric and gravity surveys. The preferred 3D resistivity model confirmed the presence of a fault system and a graben system that was filled with conductive bodies (~1–15 Ωm) corresponding to alluvium deposits. This result was in accordance with the 2D density model inferred from the gravity data, where a low-density value indicates the presence of a graben zone. The conceptual model of Limboto Lake—Pentadio was constructed using the information from the MT and gravity results, and from the geological study. The conceptual model illustrates the geothermal system in Limboto Lake—Pentadio, which is controlled by the fault system and the Gorontalo graben system

Resistivity and Density Structure of Limboto Lake—Pentadio, Gorontalo, Indonesia Based on Magnetotelluric and Gravity Data

Limboto Lake—Pentadio area is located in the province of Gorontalo on the northern arm of Sulawesi Island, Indonesia, which experienced a tectonic process from the Sula Platform collision in the mid-Miocene. This tectonic process led to the westward subduction of the early Miocene and post-collision rifting and uplifting of the arc and subduction along the North Sulawesi Trench during the Late Miocene to the Quaternary periods. The rifting process of the North Sulawesi arc resulted in the formation of the Gorontalo graben zone in the W–E direction. There are geothermal surface manifestations near Limboto Lake, such as hot spring complexes, with temperatures ranging from 74.8 °C to 78.5 °C. To understand the geological structure and prospective geothermal characteristics beneath the investigated area, we performed integrated magnetotelluric and gravity surveys. The preferred 3D resistivity model confirmed the presence of a fault system and a graben system that was filled with conductive bodies (~1–15 Ωm) corresponding to alluvium deposits. This result was in accordance with the 2D density model inferred from the gravity data, where a low-density value indicates the presence of a graben zone. The conceptual model of Limboto Lake—Pentadio was constructed using the information from the MT and gravity results, and from the geological study. The conceptual model illustrates the geothermal system in Limboto Lake—Pentadio, which is controlled by the fault system and the Gorontalo graben system