INTERPRETATION OF BOUGUER ANOMALY TO DETERMINE FAULT AND SUBSURFACE STRUCTURE AT BLAWAN-IJEN GEOTHERMAL AREA

Anjar Pranggawan Azhari, Sukir Maryanto, Arief Rachmansyah

Abstract


Gravity survey has been acquired by Gravimeter Lacoste & Romberg G-1035 at Blawan-Ijen geothermal area. It was a focusing study from previous research. The residual Bouguer anomaly data was obtain after applying gravity data reduction, reduction to horizontal plane, and upward continuation. Result of Bouguer anomaly interpretation shows occurrence of new faults and their relative movement. Blawan fault (F1), F2, F3, and F6 are normal fault. Blawan fault is main fault controlling hot springs at Blawan-Ijen geothermal area. F4 and F5 are oblique fault and forming a graben at Banyupahit River. F7 is reverse fault. Subsurface model shows that Blawan-Ijen geothermal area was dominated by the Ijen caldera forming ignimbrite (ρ1=2.670 g/cm3), embedded shale and sand (ρ2=2.644 g/cm3) as Blawan lake sediments, magma intrusion (ρ3=2.814 g/cm3 & ρ7=2.821 g/cm3), andesite rock (ρ4=2.448 g/cm3) as geothermal reservoir, pyroclastic air fall deposits (ρ5=2.613 g/cm3) from Mt. Blau, and lava flow (ρ6=2.890 g/cm3).

Keywords


gravity; lineament; Bouguer anomaly; new fault; Blawan; geothermal; subsurface

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References


Hinsberg V, Berlo K, Bergen M, Jones AW. Extreme Alteration by Hyperacidic Brines at Kawah Ijen Volcano, East Java, Indonesia: Textural and Meniralogical Imprint. Journal of Volcanology and Geothermal Researrch [Internet]. 2010 Dec[cited 2014 Dec 12];198(1-2):253-265. Available from:http://www.sciencedirect.com/science/article/pii/S037702731000288X doi:10.1016/j.jvolgeores.2010.09.002

Zaenuddin A, Wahyudin D, Surmayadi M, Kusdinar E. Prakiraan Bahaya Letusan Gunung Api Ijen Jawa Timur. Jurnal Lingkungan dan Bencana Geologi [Internet]. 2012 Aug [cited 2014 Dec 19];3(2):109-132. Available from:http://www.bgl.esdm.go.id/publication/kcfinder/files/article/JLBG%2020120204.pdf.

Bergen MJ, Bernard A, Sumarti S, Sriwana T, Sitorus K. Crater Lakes of Java: Dieng, Kelud and Ijen. Bali: Excursion Guidebook IAVCEI General Assembly, 2000.

Sidarto, Suwarti T, Sudana D. Peta Geologi Lembar Banyuwangi, Jawa, Scale 1:100.000. Bandung: Pusat Penelitian dan Pengembangan Geologi; 1993.

Sujanto, SyarifuddinMZ, Sitorus K. Geological Map of The Ijen Caldera Complex, East Java. Scale 1:50.000. Bandung: Direktorat Vulkanologi Indonesia; 1988.

Afandi A, Maryanto S, Rachmansyah A. Identifikasi Reservoar Panasbumi Dengan Metode Geomagnetik Daerah Blawan Kecamatan Sempol Kabupaten Bondowoso. Journal Neutrino [Internet]. 2013 Oct [cited 2014 Dec 12];6(1):1-10. Available from:http://ejournal.uin-malang.ac.id/index.php/NEUTRINO/article/viewFile/2441/4429doi:10.18860/neu.v0i0.2441.

Raehanayati, Maryanto S, Rachmansyah A. Studi Potensi Geotermal Blawan-Ijen, Jawa Timur Berdasarkan Metode Gravity. Journal Neutrino [Internet]. 2013 Oct [cited 2014 Dec 12];6(1):31-39. Available from:http://ejournal.uin-malang.ac.id/index.php/NEUTRINO/article/viewFile/2444/4434doi:10.18860/neu.v0i0.2444.

Suciningtyas IK, Maryanto S, Rachmansyah A. Sebaran Mata Air Panas Blawan-Ijen Berdasarkan Data Geolistrik Resistivitas. Natural B. 2013 Oct;2(2):164-171.

Telford WM, Geldart LP, Sheriff RE. Applied Geophysics Second Edition. Cambridge: Cambridge University Press;1990.

Arafin S.Relative Bouguer Anomaly. The Leading Edge. 2004 Sep;23(9):850-851.

Setyawan A. Kajian Metode Sumber Ekivalen Titik Massa Pada Proses Pengangkatan Data Gravitasi Ke Bidang Datar. Berkala Fisika [Internet]. 2005 Jan [cited 2014 Dec 25];8(1):7-10. Available from:http://eprints.undip.ac.id/1654/1/Kajian_Metode_Sumber_Ekivalen_Titik_Massa_pada_Proses_Pengangkatan_Data_Gravitasi_ke_Bidang_Datar.pdf.

Riani E, Maryanto S, Rachmansyah A. Subsurface Geological Survey Based on Gravity Method in Ijen Volcano, East Java. Physics Student Journal UB [Internet]. 2013 [cited 2014 Dec 12];l(1):64-66. Available from:http://physics.studentjournal.ub.ac.id/index.php/psj/article/viewFile/16/19.

Utama AP, Dwinanto A, Situmorang J, Hikmi M, Irshamukhti.Green Field Geothermal System in Java, Indonesia. In: Suryantini. 1st ITB Geothermal Workshop 2012; 2012 Mar 6-8; Bandung. Bandung: ITB Publisher; 2012.




DOI: https://doi.org/10.18860/neu.v9i1.3664

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