West Sumatra is one of a geothermal potential in Indonesia because of interaction between Eurasian and Indo-Australian tectonic. The existence of volcanoes produces geothermal potential with lithology andesite, tuff, and lapilli lava in the Marapi Mountain complex, which elongated at NW-SE direction as a result of NE-SW subduction. The remote sensing method specifically with Composite Band 567 and Lineament Density Analysis (LDA) found anomaly with the permeability value of prospects ranged from 2.05 to 4.76% per km2 (highest density value) with general direction is in the southeast-northwest which in line with the Sumatra structural pattern.  Based on geological data, argillic alteration was found with geothermal manifestations consisting of hot springs. Through geochemical analysis, the fluid type of hot water sample (temperature of 48.66oC) is in the immature water zone; occur with the presence of carbonate sinter. Geophysical analysis using the magnetotelluric (MT) method to identified geothermal systems such as cap rock with low resistivity (<30 ohm.m) and reservoirs with moderate resistivity (31-300 ohm.m). The correlation between remote sensing, geochemistry, and magnetotelluric could determine the geothermal potential in West Sumatra.

Geothermal energy is a clean alternative energy resource. Southern Ogan Komering Ulu (OKU), South Sumatera, is a geothermal prospect area because of the interaction between the Eurasian and Indo-Australian tectonic plates. It causes geological structures growth and the activity of volcanism in the area. Based on geological data, geothermal in southern OKU is indicated by the existence of 40-93 ºC temperature hot springs. Geological data based on remote sensing methods can determine the lineament. Geophysical data with gravity and magnetotelluric can identify the type of rock and the subsurface geological structure based on rock density and resistivity. Based on geological and gravity data indicates the presence of geological formations lead northwest-southeast, which is estimated as the geothermal fluid pathway with the suitability to the location of hot springs. The magnetotelluric data shows the geothermal reservoir rocks (clastic sedimentary rock) located at (-500)-(-2.500) meters depth with 30-200 Ωm resistivity.

Indonesia merupakan negara yang kaya akan sumberdaya alam, baik sumberdaya alam yang bersifat terbarukan maupun non terbarukan. Salah satu sumber saya yang non terbarukan tetapi jumlahnya melimpah di Indonesia adalah batubara. Batubara di Indonesia sebagian besar tersebar di pulau Sumatra dan juga Kalimantan. Untuk di pulau sumatera, tepat nya di sumsel, batubara melimpah di formasi muara enim. Adapun batubara di muara enim sebagian besar merupakan kualitas rendah, sedangkan sisanya adalah kualitas tinggi. Batubara kualitas tinggi biasanya digunakan guna pembangkit listrik tenaga uap. Seiring berjalannya waktu, batubara kualitas tinggi semakin habis. Diperlukan inovasi guna memanfaatkan batubara kualitas rendah yang melimpah tersebut. Yaitu dengan coal bed methane. CBM merupakan gas Methane yang terdapat dan terbentuk pada Batubara selama terjadi aktivitas mikrobial (biogenic) atau panas (thermogenic) dalam proses pembentukan Batubara. Gas ini terbentuk selama proses pematangan dari batubara. Salah satu hal yang berperan besardalam cbm adalah nilai gas content (GC) dan gas in place (GIP). gas content merupakan banyaknya kandungan gas meterkubik per ton,sedangkan gas in place merupakan jumlah gas yang terkandung pada area tertentu. nilai gas content di dapatkan dari perhitungan metode kim menggunakan data proksimat batubara sedangkan gas in place didapatkan dari perhitungan rumus mavor&netson. Berdasarkan perhitungan formula kim dan rumus mavor&netson lokasi penelitian berpotensi sebagai pengembangan Coal Bed Methane.

Aktivitas tektonik dan magmatisme randukuning menjadi sebuah daya tarik tersendiri bagi geologist dan geophysicst untuk melakukan penelitian lebih lanjut. Terdapatnya batuan induk berupa lava dasit dan batuan beku andesit dari formasi mandalika, serta struktur geologi yang berkembang, menyebakan terjadinya proses alterasi batuan hingga membentuk mineralisasi bijih. Pendekatan terintegrasi geofisika metode geomagnetik dan Induced Polarization dilakukan untuk mendeliniasi struktur geologi serta menzonasi daerah prospek mineralisasi secara horizontal dan vertikal. Pengambilan data dilakukan melalui analisa data open source serta data sekunder, kemudian dilakukan pengolahan data untuk mendapatkan model anomaly 2D. Hasil interpretasi pada data magnetic dengan menggunakan filter Reduce to Pole – High pass menunjukkan adanya pola anomali magnetic rendah -4.9 hingga -0.8 nT pada bagian barat yang di indikasikan akibat adanya struktur geologi serta intensitas alterasi yang tingi. Perbandingan hasil filter RTP dengan Horizontal Gradient menunjukkan adanya pola anomaly tinggi 0.001 hingga 0.0017 nT/m pada bagian timur laut dan barat daya, yang di interpretasikan sebagai respon dari struktur geologi yang terisi oleh mineralisasi. Berdasarkan penampang geolistrik induced polarization, terdapat mineral kalkopirit pada kedalaman 20-30 m dengan chargeabilitas 4-9 msec dengan resistivitas >200 Ωm. Hasil dari integrasi ini menunjukkan terdapatnya potensi endapan emas pada kavling timur laut dan barat daya daerah penelitian

The gold deposit of the low sulfidation epithermal system at the Randu Kuning prospect, Wonogiri, Central Java is the effect of magmatism during the Oligocene due to microdiorite intrusion. The magmatism causes a mineralization process that fills the fractures in the rock. The mineralized of ores that formed in the study area are pyrite, chalcopyrite, sphalerite, galena, electrum and native gold, magnetite and hematite. The appropriate geophysical method to this case study is using the geomagnetic and geoelectric Induced Polarization method. The application of the geomagnetic method aims to delineate mineralized zones and geological structures as channel way for hydrothermal fluids. The results of the geomagnetic method are in the form of a map of Total Magnetic Intensity carried out by filters such as Reduce to Pole (RTP) - High pass (HP) and Horizontal Gradient (HG). The west side of RTP - HP anomaly shows a low response of -4.9 to -0.8 nT due to intensely mineralized rock and the presence of fractures. The comparison between RTP - HP anomaly and HG anomaly shows the suitability due to intense mineralization which reduces the fault anomaly. A high HG value area of 0.001-0.0017 nT/m is interpreted as a mineralized fault. This can be seen from the alteration map which shows the continuity of veins from measurements in the field. The application of the geoelectric Induced Polarization method aims to identify associated mineral of gold vertically subsurface. Based on the results of geoelectric Induced Polarization data shows that there are chalcopyrite minerals at a depth of 20-30 m with a chargeability of 4-9 msec which is located in intrusion of igneous rock with a resistivity >200 Ωm. Based on geomagnetic geoelectric data, it can identify potential gold deposits in the Randu Kuning area, Wonogiri, Central Java.