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OPTIMASI PERAWATAN SISTEM ELEKTRIK UNTUK MEMPERTAHANKAN KELANGSUNGAN OPERASI RSG-GAS Saepuloh, Asep
REAKTOR - Buletin Pengelolaan Reaktor Nuklir Vol 9, No 2 (2012): Oktober 2012
Publisher : REAKTOR - Buletin Pengelolaan Reaktor Nuklir

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Abstract

ABSTRACT ELECTRICAL SYSTEMS MAINTENANCE OPTIMATION FOR KEEPS GOING RSG-GAS OPERATIONS. Operation since the founding in 1987 to the present time can still be maintained in good condition, this can not be separated from systems that support. Destination of the paper to give some feedback to improve the continuity of care activities that RSG-GAS operation can be maintained. Scope of writing describes some methods of maintenance to maximize program maintenance activities. The results achieved are the efforts to find a solution of the internal and external obstacles that hinder the optimization of maintenance, such as; revitalizing the systems, components and equipment, the proposed recruitment of new human resources, compliance with the operating schedule, document storage of maintenance more tidy for easy search, timeliness and management control should run fine. Optimizing maintenance electrical system was able to maintain continuity of operations RSG-GAS until now. Keywords: Maintenance optimation,RSG-GAS operations OPTIMASI PERAWATAN SISTEM ELEKTRIK UNTUK MEMPERTAHANKAN KELANGSUNGAN OPERASI RSG-GAS. Operasi reaktor sejak diresmikannya tahun 1987 hingga saat ini masih dalam kondisi baik, ini tidak terlepas dari perawatan sistem-sistem pendukungnya. Tujuan penulisan makalah memberikan beberapa masukan untuk meningkatkan kegiatan perawatan agar kelangsungan operasi RSG-GAS dapat tetap dipertahankan. Lingkup penulisan menjelaskan beberapa metode perawatan dengan memaksimalkan program kegiatan perawatan. Hasil yang dicapai adalah dengan upaya mencari solusi dari kendala internal maupun eksternal yang menghambat optimasi perawatan, seperti ; melakukan revitalisasi pada sistem, komponen dan peralatan, usulan perekrutan sumber daya manusia baru, kesesuaian dengan jadual operasi, penyimpanan dokumen perawatan yang lebih rapih agar mudah telusur, ketepatan waktu serta kontrol manajemen berjalan lebih baik. Optimasi perawatan sistem elektrik terbukti mampu untuk mempertahankan kelangsungan operasi RSG-GAS hingga saat ini.   Kata kunci : Optimasi perawatan, operasi RSG-GAS
EVALUASI PENYEBAB GANGGUAN MESIN DIESEL BRV10 DI RSG-GAS Saepuloh, Asep; Kiswanto, Kiswanto; Taufiq, Muhammad; Suraniyanto, Yuyut
REAKTOR - Buletin Pengelolaan Reaktor Nuklir Vol 11, No 1 (2014): April 2014
Publisher : REAKTOR - Buletin Pengelolaan Reaktor Nuklir

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Abstract

Diesel generator merupakan salah satu komponen penting pemasok daya listrik darurat ketika catu daya listrik utama mengalami gangguan. Tidak dapat beroperasinya mesin Diesel akan berdampak serius kepada pengoperasian reaktor. Tulisan ini bertujuan untuk mengevaluasi penyebab gangguan Diesel generator BRV10 Reaktor Serba Guna GA Siwabessy yang terjadi pada awal 2014. Peristiwa ini cukup menjadikan perhatian karena dipandang penyebabnya unusual. Evaluasi dilakukan dengan menginvestigasi sebab-sebab gangguan, melakukan langkah perbaikan, uji fungsi serta  mengantisipasi agar kejadian yang sama tidak berulang kembali dimasa yang akan datang. Dari hasil evaluasi diketahui bahwa penyebab gangguan Diesel adalah tercampurnya solar dengan air dan lumpur yang diperkiraan sudah tertimbun lama di dalam tangki bahan bakar mesin Diesel. Dipercaya penyebabnya adalah perawatan tangki bahan bakar kurang optimalABSTRACT EVALUATION OF the BRV 10 diesel engine disruption of the Multi Purpose Reactor GA siwabessy Reactor. Diesel generator is one of the important components of emergency electrical power supply when the main power supply is disrupted. Unable to operation of diesel engines will have a serious impact to the operation of the reactor This paper aims to evaluate the cause of disruption of the diesel generator BRV10 at the Multi Purpose Reactor GA Siwabessy occurred in 2014. This event makes enough attention because its cause is deemed unusual. Evaluation is done by investigating the causes of the disorder, do the repair, test functions and anticipate that similar events do not recur in the future. From the results of the evaluation of the causes of disorders known that diesel is a diesel mixing with water and mud that had buried long estimated in the diesel engine fuel tank. Is believed to cause the fuel tank care is less than optimal
Interpretasi Vulkanostratigrafi Daerah Mamuju Berdasarkan Analisis Citra Landsat-8 Indrastomo, Frederikus Dian; Sukadana, I Gde; Saepuloh, Asep; Harsolumakso, Agus Handoyo; Kamajati, Dhatu
Eksplorium Buletin Pusat Teknologi Bahan Galian Nuklir Vol 36, No 2 (2015): November 2015
Publisher : Pusat Teknologi Bahan Galian Nuklir - BATAN

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Abstract

Daerah Mamuju dan sekitarnya umumnya disusun oleh batuan gunung api. Batuan sedimen vulkanoklastik dan batugamping berada di atas batuan gunung api. Aktivitas gunung api membentuk beberapa morfologi unik seperti kawah, kubah lava, dan jalur hembusan piroklastika sebagai produknya. Produk tersebut diidentifikasi berdasarkan karakter bentuk-bentuk melingkar di citra Landsat-8. Hasil koreksi geometrik dan atmosferik, interpretasi visual pada citra Landsat-8 dilakukan untuk mengidentifikasi struktur, geomorfologi, dan kondisi geologi daerah tersebut. Struktur geologi regional menunjukkan kecenderungan arah tenggara – baratlaut yang mempengaruhi pembentukan gunung api Adang. Geomorfologi daerah tersebut diklasifikasikan menjadi 16 satuan geomorfologi berdasarkan aspek genetisnya, yaitu punggungan blok sesar Sumare, punggungan kuesta Mamuju, kawah erupsi Adang, kawah erupsi Labuhan Ranau, kawah erupsi Sumare, kerucut gunung api Ampalas, kubah lava Adang, bukit intrusi Labuhan Ranau, punggungan aliran piroklastik Adang, punggungan aliran piroklastik Sumare, perbukitan sisa gunung api Adang, perbukitan sisa gunung api Malunda, perbukitan sisa gunung api Talaya, perbukitan karst Tapalang, dan dataran aluvial Mamuju, dataran teras terumbu Karampuang. Berdasarkan hasil interpretasi citra Landsat-8 dan konfirmasi lapangan, geologi daerah Mamuju dibagi menjadi batuan gunung api dan batuan sedimen. Batuan gunung api terbagi menjadi dua kelompok, yaitu Kompleks Talaya dan Kompleks Mamuju. Kompleks Talaya terdiri atas batuan gunung api Mambi, Malunda, dan Kalukku berkomposisi andesit, sementara Kompleks Mamuju terdiri atas batuan gunung api Botteng, Ahu, Tapalang, Adang, Ampalas, Sumare, dan Labuhan Ranau berkomposisi andesit sampai basal leusit. Vulkanostratigrafi daerah ini disusun berdasarkan analisis struktur, geomorfologi, dan distribusi litologi. Vulkanostratigrafi daerah Mamuju diklasifikasikan ke dalam Khuluk Talaya dan Khuluk Adang. Khuluk Talaya terdiri atas Gumuk Mambi, Gumuk Malunda, dan Gumuk Kalukku. Khuluk Mamuju terdiri atas Gumuk Botteng, Gumuk Ahu, Gumuk Tapalang, Gumuk Adang, Gumuk Ampalas, Gumuk Sumare, dan Gumuk Labuhan Ranau. Kata kunci:vulkanostratigrafi, Landsat-8, Mamuju, geologi
Pemetaan Geologi Gunung Api Dijital Daerah Ngebel, Madiun berdasarkan Data Reflektansi dan Suseptibilitas Magnetik Batuan Saepuloh, Asep; Andrean Saputra, Raditya; Sumintadireja, Prihadi
Jurnal Geologi dan Sumberdaya Mineral Vol 18, No 4 (2017): Jurnal Geologi dan Sumberdaya Mineral
Publisher : Pusat Survei Geologi

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Abstract

This study was taken as a part of volcano geology mapping at Ngebel area including volcanostratigraphy and structural geology interpretations by optimizing the satellite remote sensing and terestrial data. Ngebel area is located at the western flank of Mt. Wilis volcanic complex, Madiun District, East Java, Indonesia. The purpose of this study is to obtain the effectiveness of atmospherically corrected satellite image of Landsat-8 OLI (Operational Land Imager) TIRS (Thermal Infrared Sensor) and rock magnetic susceptibility for identifying volcanic products. The Landsat-8 OLI/TIRS image processing is performed in two steps: pre and post field observation. The pre field observation step was treated by processing and analysing the Landsat-8 OLI/TIRS to produce geomorphological units, circular/linear feature, rock unit boundary, and interpreted eruption center by examining image color, tone, and texture. Furthermore, the reflectance spectra analyses of Landsat-8 OLI/TIRS were obtained to define detailed volcanic product unit boundary after the field observation performed. Magnetic susceptibility of the rocks was used to classify the volcanostratigraphic units based on their magnetization degree of the induced rocks. Considering the  magnetic susceptibility, there are suggested two groups of volcanic unit or Hummocks (Gumuk): Hummock of Ngebel with low susceptibility (9.9×10-3 – 20.7×10-3) and Hummock of Manyutan with medium (20.7×10-3 – 48.7×10-3) to high susceptibility (≥48.7×10-3). Noticing the reflectance spectra of Landsat-8 OLI/TIRS, it can be defined five volcanic rock units: pyroclastic fall Ngebel (reflectance value at  0.63 – 0.71), pyroclastic flows Ngebel (reflectance value at 0.71 – 0.74),  pyroclastic flow Manyutan (reflectance value at 0.74 – 0.78), lava Manyutan 1 (reflectance value at 0.78 – 0,84), and Lava Manyutan 2 (reflectance value at  ≥0.84).Keyword: Volcanostratigraphy, Landsat-8 OLI/TIRS, magnetic susceptibility, reflectance, Ngebel
Interpretasi Vulkanostratigrafi Daerah Mamuju Berdasarkan Analisis Citra Landsat-8 Indrastomo, Frederikus Dian; Sukadana, I Gde; Saepuloh, Asep; Harsolumakso, Agus Handoyo; Kamajati, Dhatu
EKSPLORIUM Vol 36, No 2 (2015): November 2015
Publisher : Pusat Teknologi Bahan Galian Nuklir - BATAN

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1482.403 KB) | DOI: 10.17146/eksplorium.2015.36.2.2772

Abstract

Daerah Mamuju dan sekitarnya umumnya disusun oleh batuan gunung api. Batuan sedimen vulkanoklastik dan batugamping berada di atas batuan gunung api. Aktivitas gunung api membentuk beberapa morfologi unik seperti kawah, kubah lava, dan jalur hembusan piroklastika sebagai produknya. Produk tersebut diidentifikasi berdasarkan karakter bentuk-bentuk melingkar di citra Landsat-8. Hasil koreksi geometrik dan atmosferik, interpretasi visual pada citra Landsat-8 dilakukan untuk mengidentifikasi struktur, geomorfologi, dan kondisi geologi daerah tersebut. Struktur geologi regional menunjukkan kecenderungan arah tenggara – baratlaut yang mempengaruhi pembentukan gunung api Adang. Geomorfologi daerah tersebut diklasifikasikan menjadi 16 satuan geomorfologi berdasarkan aspek genetisnya, yaitu punggungan blok sesar Sumare, punggungan kuesta Mamuju, kawah erupsi Adang, kawah erupsi Labuhan Ranau, kawah erupsi Sumare, kerucut gunung api Ampalas, kubah lava Adang, bukit intrusi Labuhan Ranau, punggungan aliran piroklastik Adang, punggungan aliran piroklastik Sumare, perbukitan sisa gunung api Adang, perbukitan sisa gunung api Malunda, perbukitan sisa gunung api Talaya, perbukitan karst Tapalang, dan dataran aluvial Mamuju, dataran teras terumbu Karampuang. Berdasarkan hasil interpretasi citra Landsat-8 dan konfirmasi lapangan, geologi daerah Mamuju dibagi menjadi batuan gunung api dan batuan sedimen. Batuan gunung api terbagi menjadi dua kelompok, yaitu Kompleks Talaya dan Kompleks Mamuju. Kompleks Talaya terdiri atas batuan gunung api Mambi, Malunda, dan Kalukku berkomposisi andesit, sementara Kompleks Mamuju terdiri atas batuan gunung api Botteng, Ahu, Tapalang, Adang, Ampalas, Sumare, dan Labuhan Ranau berkomposisi andesit sampai basal leusit. Vulkanostratigrafi daerah ini disusun berdasarkan analisis struktur, geomorfologi, dan distribusi litologi. Vulkanostratigrafi daerah Mamuju diklasifikasikan ke dalam Khuluk Talaya dan Khuluk Adang. Khuluk Talaya terdiri atas Gumuk Mambi, Gumuk Malunda, dan Gumuk Kalukku. Khuluk Mamuju terdiri atas Gumuk Botteng, Gumuk Ahu, Gumuk Tapalang, Gumuk Adang, Gumuk Ampalas, Gumuk Sumare, dan Gumuk Labuhan Ranau. Mamuju and its surrounding area are constructed mainly by volcanic rocks. Volcanoclastic sedimentary rocks and limestones are laid above the volcanic rocks. Volcanic activities create some unique morphologies such as craters, lava domes, and pyroclastic flow paths as their volcanic products. These products are identified from their circular features characters on Landsat-8 imagery. After geometric and atmospheric corrections had been done, a visual interpretation on Landsat-8 imagery was conducted to identify structure, geomorphology, and geological condition of the area. Regional geological structures show trend to southeast – northwest direction which is affects the formation of Adang volcano. Geomorphology of the area are classified into 16 geomorphology units based on their genetic aspects, i.e Sumare fault block ridge, Mamuju cuesta ridge, Adang eruption crater, Labuhan Ranau eruption crater, Sumare eruption crater, Ampalas volcanic cone, Adang lava dome, Labuhan Ranau intrusion hill, Adang pyroclastic flow ridge, Sumare pyroclastic flow ridge, Adang volcanic remnant hills, Malunda volcanic remnant hills, Talaya volcanic remnant hills, Tapalang karst hills, Mamuju alluvium plains, and Karampuang reef terrace plains. Based on the Landsat-8 imagery interpretation result and field confirmation, the geology of Mamuju area is divided into volcanic rocks and sedimentary rocks. There are two groups of volcanic rocks; Talaya complex and Mamuju complex. The Talaya complex consists of Mambi, Malunda, and Kalukku volcanic rocks with andesitic composition, while Mamuju complex consist of Botteng, Ahu, Tapalang, Adang, Ampalas, Sumare, danLabuhanRanau volcanic rocks with andesite to leucitic basalt composition. The volcanostratigraphy of Mamuju area was constructed based on its structure, geomorphology and lithology distribution analysis. Volcanostratigraphy of Mamuju area is classified into Khuluk Talaya and Khuluk Mamuju. The Khuluk Talaya consists of Gumuk Mambi, Gumuk Malunda, and Gumuk Kalukku, while Khuluk Mamuju consists of Gumuk Botteng, Gumuk Ahu, Gumuk Tapalang, Gumuk Adang, Gumuk Ampalas, Gumuk Sumare, and Gumuk Labuhan Ranau.
OPTIMASI PERFORMA GENSET SEBAGAI CATU DAYA DARURAT DI RSG-GAS Saepuloh, Asep; Andriyanto, Yayan
REAKTOR - Buletin Pengelolaan Reaktor Nuklir Vol 14, No 1 (2017): April 2017
Publisher : REAKTOR - Buletin Pengelolaan Reaktor Nuklir

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1236.328 KB) | DOI: 10.17146/bprn.2017.v14i1.3896

Abstract

ABSTRAK OPTIMASI PERFORMA GENSET SEBAGAI CATU DAYA DARURAT DI RSG-GAS. Pada instalasi kelistrikan RSG-GAS terdapat 3 unit genset yaitu BRV10/ 20/30 yang berfungsi sebagai catu daya darurat. Genset tersebut memegang peranan sangat penting dalam ketersediaan beban kelistrikan. Mesin genset beroperasi pada  beberapa kondisi, antara lain ; bila catu daya utama gangguan, saat test run, dan pasca perbaikan. Tahun 2016 terjadi kegagalan operasi pada saat test run ditunjukan dengan ; mesin tiba-tiba mati, level air radiator cepat berkurang, suhu mesin cepat panas, oli berubah warna menjadi pekat keputih-putihan. Untuk mengatasinya dilakukan langkah investigasi gangguan, analisa, serta perbaikan. Kegiatan semi overhaul dilakukan pada genset BRV20 oleh tenaga profesional dengan tujuan mengembalikan performa genset BRV20 ke kondisi semula. Berdasarkan hasil uji fungsi pasca perbaikan disimpulkan bahwa gangguan operasi sudah tidak terjadi lagi, suhu oli  CT-151 yang sebelumnya 127 °C menjadi 118 °C, suhu air pendingin CT-021 yang sebelumnya  99 °C menjadi  85 °C, harga-harga parameter operasi lainnya masih berada dalam batas yang ditetapkan di dalam formulir test run BRV 10/20/30. Kata kunci : performa genset BRV20, catu daya darurat ABSTRACT OPTIMATION PERFORMANCE OF GENERATOR SET AS EMERGENCY POWER SUPPLY IN RSG-GAS. In the electrical installation RSG-GAS genset there are 3 units namely BRV10/20/30 that serves as an emergency power supply. The generator has an important role in the availability of the electrical load. Genset operates on several conditions, among others; when the main power supply interruption, during a test run, and post-repair. Last year 2016 operating failure occurs during the test run is shown; engine suddenly dies, radiator water level rapidly reduced, the engine temperature heat up quickly, the oil changes color to thick whitish. To overcome the interference investigations carried out step, analysis and improvement. The activities carried out in the genset overhaul semi BRV20 by professionals with the aim of restoring the performance of genset BRV20 to its original state. Based on post-repair function test results concluded that the interruption of operations no longer exist, the oil temperature CT-151 previously 127 °C to 118 °C, and cooling water temperature CT-021 before    99 °C to 85 °C, the price of the operating parameters still within the limits specified in the test run form BRV 10/20/30. Keywords: performance of diesel BRV20, emergency power supply 
Satellite Imagery for Classification of Rice Growth Phase Using Freeman Decomposition in Indramayu, West Java, Indonesia Nurtyawan, Rian; Saepuloh, Asep; Harto, Agung Budi; Wikantika, Ketut; Kondoh, Akihiko
HAYATI Journal of Biosciences Vol 25, No 3 (2018): July 2018
Publisher : Bogor Agricultural University, Indonesia

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.4308/hjb.25.3.126

Abstract

  Monitoring at every growth of rice plants is an important information for determining the grain pro-duction estimation of rice. Monitoring must to be have timely work on the rice plant development. However, timely monitoring and the high accuracy of information is a challenge in remote sensing based on rice agriculture monitoring and observation. With increased quality of synthetic aperture radar (SAR) systems utilizing polarimetric information recently, the development and applications of polarimetric SAR (PolSAR) are one of the current major topics in radar remote sensing. The ad-vantages provided by PolSAR data for agricultural monitoring have been extensively studied for applications such as crop type classification and mapping, crop phenology monitoring, productivity assessment based on the sensitivity of polarimetric parameters to indicators of crop conditions. Freeman and Durden successfully decomposed fully PolSAR data into three components: Single bounce, double bounce, and volume scattering. The three-component scattering provide features for distinguishing between different surface cover types. These sensitivities assist in the identification of growing phase. The observed growing phase development in time series, reflected in the consistent temporal trends in scattering, was generally in agreement with crop phenological development stages. Supervised classification was performed on repeat-pass Radarsat-2 images, with an overall classification accuracy of 77.27% achieved using time series Fine beam data. The study demonstrated that Radarsat-2 Fine mode data provide useful information for crop monitoring and classification of rice plants.
PEMECAHAN LINEAR PROGRAMMING DUA VARIABEL MENGGUNAKAN LOGIKA FUZZY Saepuloh, Asep; Jakaria, Deni Ahmad
JURNAL TEKNIK INFORMATIKA (JUTEKIN) Vol 3, No 1 (2015): JUTEKIN
Publisher : LPPM STMIK DCI

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Abstract

Fuzzy logic is a methodology of solving the control system to be implemented in a system, ranging from a simple system, small, large, networks, multi-channel PC or workstation. Besides that, it can be implemented in hardware, software or a combination of both. Fuzzy logic provides a simple way to get definitive conclusions based on ketidaksamaran, ambiguity, imprecision, vagueness, or missing information. Fuzzy logic approach is to control the problem impersonation of someone who will make a decision.Linear programming is a way to establish a fast arrangement of a problem with a simple solution. Set of linear programming gives two reasons: (i) a lot of practical problems which can be formed as a linear programming problem, and (ii) no efficient way (eg simplex method) for solving linear programming problems. Linear programming problems is to find the values of a variable that is not known as a linear objective function that dimaksimasikan under the constraints described by linear equations.On fuzzy linear programming, will look a Z value which is the objective function to be optimized so that is subject to the restrictions are modeled using fuzzy sets. Linear programming is solved by fuzzy logic gives more precise results dibandingakan if without using fuzzy logic. This system provides an opportunity or a chance for the development of the system towards better Keyword  : Logic, Fuzzy, Linear, Programming
Identifikasi Potensi Rembesan Mikro di Lapangan Migas Melalui Deteksi Mineral Lempung Menggunakan Citra Landsat 8 OLI/TIRS, Studi Kasus Lapangan Migas Cekungan Jawa Barat Bagian Utara Susantoro, Tri Muji; Wikantika, Ketut; Saepuloh, Asep; Harsolumakso, Agus Handoyo
Jurnal Penginderaan Jauh dan Pengolahan Data Citra Digital Vol. 15 No. 1 Juni 2018
Publisher : Indonesian National Institute of Aeronautics and Space (LAPAN)

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (805.415 KB) | DOI: 10.30536/j.pjpdcd.2018.v15.a2779

Abstract

Clay minerals in the oil and gas field have changed with an increase of the quantities in the middle of the oil and gas field and reduction in the edges. This reduction is the effect of micro seepage from oil and gas from the subsurface. The aims of the research is to identify the potential oil and gas seepage through clay mineral mapping. The data used where Landsat 8 OLI/TIRS with recording dated September 25, 2015. The method used in the mapping of clay minerals using the ratio of 1.55-1.75 µm (Short Wave Infrared 1) and 2.08-2.35 µm (Short Wave Infrared 2). The result of Landsat 8 OLI/TIRS data processing shows the potential of anomalies in edges of the oil and gas field. The anomaly is a change in the index value of clay minerals that tend to be lower with values 1.0 to 1.5 than the middle of oil and gas field with values 1.5 to 2.0. The potential pattern of the anomaly follows the border of the oil and gas field. Field surveys show that oil and gas field based on grain size analysis is dominated by clay-sized soil. The dominant clay minerals from X-Ray Diffraction analysis are smectite (56%) and kaolinite (6%).ABSTRAKMineral lempung di lapangan migas mengalami perubahan dengan terjadinya peningkatan kandungannya pada tengah lapangan migas dan pengurangan di tepinya. Pengurangan ini merupakan efek adanya rembesan mikro dari migas yang berasal dari bawah permukaan. Kajian ini bertujuan untuk mengidentifikasi adanya potensi rembesan migas melalui pemetaan mineral lempung. Adapun data yang digunakan adalah Landsat 8 OLI/TIRS dengan perekaman tanggal 25 September 2015. Metode yang digunakan pada pemetaan mineral lempung menggunakan perbandingan panjang gelombang 1.55-1.75 µm (Short Wave Infrared 1) dengan 2.08-2.35 µm (Short Wave Infrared 2). Hasil pengolahan data Landsat 8 OLI/TIRS menunjukkan adanya potensi anomali di tepi lapangan migas. Anomali tersebut berupa perubahan nilai indeks mineral lempung yang cenderung lebih rendah yaitu dengan nilai 1,0 – 1,5 dibandingkan lokasi di tengah lapangan yaitu dengan nilai 1,5 – 2,0.  Pola potensi anomali tersebut mengikuti batas tepi lapangan migas. Survei lapangan menunjukkan bahwa pada lapangan migas berdasarkan analisis ukuran butir didominasi oleh tanah berukuran lempung. Adapun mineral lempung yang dominan dari hasil analisis XRD berupa smektit (56%) dan terdapat kaolinit (6%).
Advanced Applications of Synthetic Aperture Radar (SAR) Remote Sensing for Detecting Pre- and Syn-eruption Signatures at Mount Sinabung, North Sumatra, Indonesia Saepuloh, Asep; Mirelva, Prima Rizky; Wikantika, Ketut
Indonesian Journal on Geoscience Vol 6, No 2 (2019): in-press
Publisher : Geological Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17014/ijog.6.2.123-140

Abstract

Mount Sinabung was re-activated at August 28th, 2010 after a long repose interval. The early stage of a phreatic eruption was then followed by magmatic eruptions at September 15th, 2013 for years until now. To understand the ground surface changes accompanying the eruption periods, comprehensive analyses of surface and subsurface data are necessary, especially the condition in pre- and syn-eruption periods. This study is raised to identify ground surface and topographical changes before, intra, and after the eruption periods by analyzing the temporal signature of surface roughness, moisture, and deformation derived from Synthetic Aperture Radar (SAR) data. The time series of SAR backscattering intensity were analyzed prior to and after the early eruption periods to know the lateral ground surface changes including estimated lava dome roughness and surface moisture. Meanwhile, the atmospherically corrected Differential Interferometric SAR (D-InSAR) method was also applied to know the vertical topographical changes prior to the eruptions. The atmospheric correction based on modified Referenced Linear Correlation (mRLC) was applied to each D-InSAR pair to exclude the atmospheric phase delay from the deformation signal. The changes of surface moistures on syn-eruptions were estimated by calculating dielectric constant from SAR polarimetric mode following Dubois model. Twenty-one Phased Array type L-band SAR (PALSAR) data on board Advanced Land Observing Satellite (ALOS) and nine Sentinel-1A SAR data were used in this study with the acquisition date between February 2006 and February 2017. For D-InSAR purposes, the ALOS PALSAR data were paired to generate twenty interferograms. Based on the D-InSAR deformation, three times inflation-deflation periods were observed prior to the early eruption at August 28th 2010. The first and second inflation-deflation periods at the end of 2008 and middle 2009 presented migration of magma batches and dike generations in the deep reservoir. The third inflation-deflation periods in the middle of 2010 served as a precursor signal presenting magma feeding to the shallow reservoir. The summit was inflated about 1.4 cm and followed by the eruptions. The deflation of about 2.3 cm indicated the release pressure and temperature in the shallow reservoir after the early eruption at August 28th, 2010. The last inflation-deflation period was also confirmed by the increase of the lava dome roughness size from 5,121 m2 on July to 6,584 m2 on August. The summit then inflated again about 1.1 cm after the first eruption and followed by unrest periods presented by lava dome growth and destruction at September 15th, 2013. The volcanic products including lava and pyroclastics strongly affected the moisture of surface layer. The volcanic products were observed to reduce the surface moisture within syn-eruption periods. The hot materials are presumed responsible for the evaporation of the surface moisture as well.