Multi Geophysical Observations at Blawan - Ijen Volcano Geothermal Complex for Regional Development

Abstract

Geothermal resource investigation by using multi geophysical observation was accomplished for Blawan-Ijen geothermal system. Geological and surface investigation found about 21 hot springs have been found in Blawan area with the surface temperature ranged from about 40 o C-55 o C. Based on resistivity and GPR data known that the underground seepage of hot water following the fault direction. This fault structure is identified based on the high distribution of microseismicity and thermal infrared remote sensing (TIR) analysis which associated with high land surface temperature (LST). Meanwhile, the heat source of Blawan-Ijen geothermal system are found in the southwest part based on high magnetic anomaly which represents the igneous rocks. All methods used shows the results indicating that Blawan-Ijen volcano complex is an interesting area for geothermal energy development and suitable for pilot project on regional development of volcano geothermal region.

Tinjauan Terhadap Pengembangan Potensi Panas Bumi Blawan-Ijen, Jawa Timur

“…Lebih lanjut, terlihat bahwa struktur patahan Blawan (F1) diikuti oleh pola suhu permukaan yang tinggi. sehingga diperkirakan patahan tersebut merupakan pengontrol terbentuknya manifestasi panas bumi di daerah Blawan-Ijen (Gambar 2b) [12].…”

“…Berdasarkan Gambar 2b, patahan Blawan mengikuti kontur rapat antara anonali Bouger positif dan negatif. Kerapatan yang tinggi di ujung utara patahan Blawan diinterpretasikan sebagai fluida panas intrusi di sekitar patahan dan reservoir panas bumi [12]. Hasil penelitian dengan menggunanakan geomagnetik menunjukkan bahwa reservoir panas bumi terdapat di kedalaman sekitar 1900m dengan temperatur 100ºC, hal ini ditunjukkan dengan nilai suseptibilitas yang rendah [14].…”

“…Distribusi temperatur berdasaran data citra satelit [11], (b). Overlay antara temperatur permukaan, patahan dan anomali Bouger [12], (c). Korelasi antara hasil MT 3D dan pengeboran [16], (d).…”

“…MCG sudah melakukan studi geologi dan geofisika untuk menentukan cadangan panas bumi [20]. Manajemen industri dalam pengusahaan panas bumi (eksplorasi dan eksploitasi) membutuhkan biaya investasi yang tinggi, memiliki risiko tinggi (risiko ketidakpastian geologi, teknis, ekonomi, dan politik) dan membutuhkan teknologi modern [12]. Dengan demikian, diperlukan kerja sama yang kuat antara pemerintah, stakeholders, maupun elemen masyarakat dalam mewujudkan pengembangan potensi panas bumi sebagai pembangkit listrik 2×55 MW.…”

Spatio-Temporal Change of Land Surface Temperature at Tiris Geothermal Potential Area, East Java, Indonesia.

“…Based on Indonesia Minister of Energy and Mineral Resources [1], Tiris has geothermal potential about 74 MWe allegedly around the Lamongan Volcano. Before this geothermal potential was exploited, some geophysical studies are needed such as those carried out in potential geothermal areas, such as Songgoriti-Kasinan, Cangar, Blawan, and Wurung Creater [2][3][4][5][6][7][8][9]. Preliminary study using gravity data has been done in 2018 by Maryanto et al [10], with result that Tiris Geothermal Area is volcano hosted geothermal.…”