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In recent years, dozen low-intensity earthquakes occurred in southern Garut, West Java Indonesia; two of them were reported destructive. However, those shallow earthquake clusters are hardly associated with well-known active faults in the area. Hence, we conducted 3D gravity combined with 2D magnetotellurics (MT) inversions to study the subsurface. Gravity and MT modeling confirm a basin with around 5 km depth consisting of two subbasins separated by a NE-SW trending local-high ridge. The local high coincides with the magmatic intrusion in geothermal fields and aligns with a series of volcanic bodies’ lineament observed on the surface. We interpret this structural high as a preexisting fault that serves as a magma pathway in the tectonomagmatic interaction. Shallow low-magnitude seismicity in the southern Garut area tends to occur in the resistive bodies. We interpret that heat from the cooling magmatic intrusion may decrease the effective fault-normal stress of the rocks, leading to a decrease in fault failure resistance and may initiate rupture. The resistivity structure around the initial rupture may affect whether or not the nucleation will end up as a large-magnitude earthquake. Furthermore, the unconsolidated young volcanic cover in this area could amplify ground shaking when earthquake occurs that might lead to more extensive damage.

Tujuan penulis melakukan penelitian ini adalah untuk mengetahui Bagaimana penerapan sistem aplikasi E-Retribusi dalam pemungutan retribusi dipasar Pemda Dinas Koperasi, Umkm Perdagangan dan Perindustrian Kabupaten Subang. Metode penelitian yang digunakan adalah pendekatan kualitatif yang bersifat deskriptif, karena penelitian ini bertujuan untuk memperoleh gambaran yang diteliti digunakan untuk mengungkapkan permasalahan dalam kinerja organisasi pemerintah dan observasi, wawancara, studi kepustakaan dan dokumentasi. Sumber data diperoleh dari informan melalui pengamatan dan wawancara secara langsung dan dokumen diperoleh dalam bentuk peraturan-peraturan dan pengolahan data. Berdasarkan penelitian, diperoleh hasil bahwa efektifitas dan efisiensi kerja bidang pengelolaan pasar dalam pemungutan retribusi pasar Dinas Koperasi, Umkm, Perdagangan dan Perindustrian Kabupaten Subang secara umum masih belum optimal. Hal ini dikarenakan unsur ketepatan kebijakan, ketepatan pelaksanaan, ketepatan waktu, ketepatan lingkungan menurut Matland efektifitas dan efisiensi kerja yaitu target yang diharapkan tidak tercapai sepenuhnya. Efektifitas dan efisiensi kerja masih manual dan terdapat petugas retribusi yang kurang memiliki keterampilan dan kemampuan di lapangan terutama dalam hal teknologi. Ketepatan waktu masih ada petugas pengelolaan retribusi pasar yang terlambat menyetorkan pendapatan retribusinya ke bendahara di dinas.

Vocational High School (SMK), being part of an integrated school in the national education system, SMK aims to prepare skilled and ready-to-work graduates. The research was conducted at SMK Lembang Subdistrict, the purpose of this study is to determine, study and analyze teacher performance and the quality of education and teaching, and the magnitude of the influence of partial and simultaneous teacher performance on teacher performance. The research methods used are descriptive surveys and explanatory surveys. Descriptive research is research that aims to obtain a description of the characteristics of teacher performance variables and the quality of education and teaching at SMK Lembang District, while verificative research is research that wants to test the truth of a hypothesis carried out through data collection in the field, in the study will test teacher performance and the quality of education and teaching. The results of the study descriptively showed the condition of teacher performance within the criteria was good, and the quality of education and teaching was in good criteria, and the results of the study verificative showed that teacher performance had a positive and significant influence partially and simultaneously on the quality of education and teaching with an R2 (R Square) value of 0.744 or 74.4% with a value outside the model of 0.255 or 25.5%.

Tujuan penelitian ini adalah untuk meningkatkan kemampuan siswa kelas XI.IPS2 SMAN 1 Cigugur yang berjumlah 26 orang siswa pada ‘seni kriya membentuk’ berbahan PVC dengan menggunakan teknik sambung dan pahat. Penelitian ini menggunakan metode penelitian tindakan kelas dengan mengimplementasikan model penelitian Kemmis dan McTaggart yang dilaksanakan dalam 2 siklus. Untuk mendapatkan data yang diperlukan dalam penelitian ini menggunakan teknik observasi, wawancara, dan penilaian produk. Selanjutnya pengolahan datanya menggunakan pendekatan kuantitatif dan kualitatif. Hasil observasi pada siklus II menunjukkan adanya peningkatan aktivitas belajar siswa mencapai 92% dan aktivitas guru mencapai 100%. Sedangkan hasil belajarnya telah menunjukkan nilai rata-rata kelas sebesar 89 dan seluruh siswa dinyatakan tuntas dalam pembelajaran tersebut. Selain itu, respon yang ditunjukkan siswa terhadap pembelajaran sangat baik. Mereka sangat menyenangi pembelajaran tersebut yang menggunakan teknik sambung dan pahat pada kriya berbahan paralon.

Gerakan tanah di kompleks perkantoran Kabupaten Sukabumi di Jajaway, Palabuhanratu, terjadi di luar perkiraan dan perencanaan pembangunan sebelumnya. Untuk melihat kondisi dan luasan daerah gerakan tanah dan dalam usaha mengurangi resiko kerugian lebih besar, diperlukan identifikasi bidang gelincir gerakan tanah di kompleks tersebut. Bidang gelincir dicari berdasarkan model tahanan jenis yang diperoleh dari survei pengukuran geolistrik. Akuisisi data dilakukan pada 7 lintasan, dengan 6 lintasan berarah utara-selatan dan 1 lintasan berarah barat-timur. Metode akusisi yang digunakan adalah tahanan jenis multielektrode dengan konfigurasi dipole-dipole. Hasil penelitian membuktikan bahwa kondisi perlapisan batuan lepas tetapi lebih berat di atas lapisan lempung merupakan salah satu penyebab kejadian pergerakan tanah. Kejadian itu sangat terlokalisir karena kondisi seperti itu tidak ditemukan pada lintasan lainnya.Kata kunci: bidang gelincir, geolistrik, gerakan tanah, konfigurasi dipole-dipole, tahanan jenisABSTRACTGround movement in the Sukabumi Regency office complex (Jajaway, Palabuhanratu), occurred unexpectedly. To reduce the potential risk, we need to identify the slip surface to detect the possibility of more landslides. The resistivity model by the dipole-dipole geoelectrical method was applied to find the slip surface. Data acquisition was carried out in 7 lines: 6 north-south lines and 1 east-west line. The resistivity models present the distribution of resistivity below the surface. Above this clay layer, there is a higher resistivity layer, which is related to sandy tuff and breccia. The condition might cause the previous creeping type of ground movement. The type of layering is not found in the other lines. Therefore we do not expect a similar ground movement would occur in those lines.Keywords: dipole-dipole configuration, geoelectrical, landslide, resistivity, slip surface

Northern part of Lombok island has a unique geological phenomenon of submarine groundwater discharge. Submarine groundwater discharge needs to be conserved for its sustainability. This study asseses groundwater vulnerability for SGD conservation in the northern part of Lombok Island Indonesia. The assessment was conducted using aquifer vulnerability index methods. Vulnerability index value in the study area is high vulnerability index. This vulnerability index is getting higher toward the coast. The layer is tuffaceous pumice layer with a hydraulic conductivity value of 5 m/day. This layer makes the aquifer in the study area very vulnerable to contamination, especially for pollution involving vertical percolation and infiltration. Protective management is needed to prevent groundwater hazard in the research location due to groundwater pollution and heavy pumping. Anthropogenic activity at the study area should be anticipated because of the high index of aquifer susceptibility at the study area.

The Batu Kalde Site is a ruin of Hindu Temple in Pangandaran, West Java, Indonesia. Despite it has been reported since 1915 and subsequently studied by several archaeological teams, a lot of aspects including geoarchaeology of this temple are still unrevealed. This preliminary study was an overview of general aspects of geoarchaeology of the temple. The result shows that the temple was constructed before the 14th century by a population of farmers and fishermen lived on the fertile coastal plain of Pangandaran in south coast of Java Island. The temple was constructed in a narrow coastal plain of a small island on a Quaternary marine sediment offshore of the present Pangandaran coast. The existing tombolo morphology of Penanjung has not been completely formed when the temple was being constructed. The temple was constructed using bedded sandstone of the Pamutuan Formation quarried from outcrops in the vicinity of the temple. This study shows that utilization of materials from local available resource might have been a model of temple construction within the classical period in the period of between the 7-14th century in West Java, Indonesia.

This research is inspired by teachers’ current state which is demanded to have competencies in designing effective and meaningful learning, fun, organizing the learning well, choosing the right approach or learning model so students can actively learn and create a student-centered learning. It is expected to enhance the competence of social attitudes, spiritual attitudes, knowledge, and skills. The enhancement itself can be seen through the results of the learning assessment. This study intends to see the implementation of active learning through the application of Pancasila and Civics education models at SMK Negeri Pancatengah which can improve students' spiritual and social competences. This research is based on Piaget and Vygotsky’s constructivist learning theory, Active Learning from Silberman (2014:9), Active Learning from Warsono (2013:5), Attitude theory from Mar’at (1982:13), the concept of social and spiritual attitudes from Mulyasa (2015:17). The approach used in this research is qualitative with descriptive method. The process of collecting data is conducted through observation, interview, documentation study, and literature study. Meanwhile, the stages of data analysis are in the form of data collection, data presentation, data reduction, and data verification/conclusion. The results of the study found by the researcher stated that the teacher has understood the concept and implementation of active learning by practicing it in the application of some active learning models such as problem-based learning, Inquiry Learning, Discovery Learning, and Project-Based Learning. Active learning plan has been carried out thoroughly. In the implementation of active learning, the teacher has demonstrated the step of applying the active learning model systematically. The implementation of the learning assessment has shown objective results in line with the improvement of students’ competencies of spiritual and social attitudes. In its implementation, the supports and challenges are not very influential so the implementation of active learning shows the success of improvement towards the competence of students' attitude. Recommendations from this study include: First, The school continually provides moral and material support, especially in terms of improving teachers' understanding of the concepts and principles of active learning, Second, The teacher is expected to be aware of models and learning strategies by growing the desire to be a learner teacher. Third, The school continues to cultivate the application of learning models and provide flexibility to teachers and students for learning innovation. Fourth: Encourage teachers to conduct classroom research or other research.

PT.Bank Pembangunan Daerah Jawa Barat dan Banten, Tbk. Adalah salah satu bank milik pemerintah yang memiliki tugas/kegiatan menghimpun dana dari masyarakat dan menyalurkan lagi kepada masyarakat dalam berbentuk kredit, serta memberikan pelayanan jasa-jasa lainnya. Salah satu jenis kredit yang diberikan oleh PT. Bank Pembangunan Daerah Jawa Barat dan Banten, Tbk adalah kredit pemilikan rumah (KPR). Berdasarkan kajian ini bahwa prosedur pemberian kredit pemilikan rumah (KPR) pada PT. Bank Pembangunan Daerah Jawa Barat dan Banten, Tbk. Terdiri dari : mengajukan surat permohonan kredit, wawancara, memenuhi persyaratan yang belum lengkap, mencari riwayat kredit calon debitur melalui database website Bank Indonesia (BI), verifikasi kunjungan (visit), penandatanganan daftar riwayat kredit beserta berkas aplikasi kredit oleh pihak Account Officer (AO), Bisnis Legal (BL), Cradit Risk (CR), manajer bisnis, pimpinan cabang, melakukan taksansi/ploting laporan pemeriksa akhir, pengecekan atas aspek yuridis atau legal atas dokumen agunan, pencairan dana kredit melalui pihak Hukum Administrai, mengingatkan kembali kepada debitur tentang jatuh tempo pembayaran angsuran kredit. PT.Bank Regional Development of West Java and Banten, Tbk. Is one of the government-owned banks that have the task or activity to raise funds from the community and channel again to the community in the form of credit, and provide other services. One type of credit provided by PT. Regional Development Bank of West Java and Banten, Tbk is a mortgage loan (KPR). Based on the results of the final task of providing homeownership loan (KPR) at PT. Regional Development Bank of West Java and Banten, Tbk. Consists of: submitting loan application letter, interviewing, fulfilling incomplete requirements, seeking credit history of debtor candidate through Bank Indonesia website (BI) website, visit verification, signing of credit history list and credit application file by Account Officer (AO), Legal Business (BL), Cradit Risk (CR), business manager, branch manager, performs taxa

Small islands depend on rainwater as a source of water. Climate variability affects changes in groundwater chemistry on small islands. Pari Island is one such small island, located in Indonesia, with an area of 41.32 ha and a population of 1,441. This study aims to assess the vulnerability of groundwater quality to climate variability based on observations from Pari Island, including the influence of tourism on groundwater. The study used traditional hydrochemistry analysis methods (Piper, Durof, Scholler, and Gibb’s diagrams), a questionnaire survey, and Standardized Precipitation Evapotranspiration Index (SPEI) analysis. The results indicate a strong correlation between SPEI-2 and the total dissolved solid content of groundwater, demonstrating that two-monthly interval precipitation has an impact on groundwater quality. The hydro chemical analysis of samples taken from dug wells shows that, geographically, the influence of climate variability on Pari Island weakened from west to east, corresponding to patterns related to the direction of the monsoon winds of tropical Indonesia. Increased tourism worsened groundwater vulnerability due to increased water demand and resultant wastewater load.

This study aims to provide input on dissemination strategies that can be carried out by the Mamuju Regency Communication and Information Service (Diskominfo) to improve information services to the community. With the existence of Law Number 14 of 2008 concerning Public Information Disclosure, it is hoped that the government can provide information that is guided by the principles of accountability, transparency and public participation in every public policy process. In the era of globalization and democracy, information disclosure is the foundation for realizing community participation in development. The research was conducted at the Office of Communication and Informatics, Mamuju Regency. The results of the study show that the local government has not accommodated the needs of the community, this is known by the demands of the people in remote areas who claim to have not received information and some have never received relevant information about government policies.

We present an interpretation of newly acquired audio-magnetotelluric data to reveal the subsurface geometry of Cimandiri Fault Zone, one of the major active faults in the western part of Java. The line section is 25 km long in a nearly north–south direction across the axes of CFZ with 24 stations of 750–1200 m spacing intervals. The 2D AMT inversion model shows two conductive zones in the southern part that may be associated to the Miocene rocks of the Southern Mountains, and a conductive zone in the northern part that is likely to be associated with Gunung Walat fold-belt. The subsurface structures of the Southern Mountains are dominated by south-dipping thrusts that may uplift the shallow marine sediments. Shallow seismicity occurred around CFZ indicating the activity of these blind thrusts.

Efforts to Improve Licensing Service Quality through Ball Pick Up Innovation. Descriptive Study on the Office of Investment and One-Stop Services in Semarang Regency, Central Java Province. This research is intended to find out how the innovation of licensing services by picking up the ball in improving the quality of licensing services at the Semarang One-Stop Service of Investment and Integrated Services. Other objectives are to find out the factors that hamper the path of innovation in pick-up licensing services and to find out the efforts made by the Semarang District One-Stop Investment Service and Integrated Services to improve the quality of licensing services. In this study the author uses the theory of Basuki Johanes (2013: 179) who sees public service innovation from relative benefits, suitability, complexity, the possibility of observable experiments. The method used in this research is inductive descriptive. Data collection is done by using interview methods, documentation, and observation. Data analysis techniques used include data reduction, data presentation and conclusion drawing. The results of the study showed that in the implementation of the licensing service innovation, picking up the ball had already been running but not yet maximally. It should be noted again about the location in implementing the licensing service for picking up the ball. The limiting factor that arises is the limited number of apparatus resources, the lack of facilities that support the innovation of ball picking licensing services, implementation that is not in accordance with standard operating procedures and lack of public awareness about the importance of licensing

One of the most powerful eruptions of the Holocene, known as the Samalas eruption, had a VEI of 7 and took place on Lombok, eastern Indonesia in 1257 CE. Thick tephra fall covered the entire island, and pyroclastic density currents (PDCs) up to 50 m thick buried almost half of Lombok. Until now, there has been no detailed study of the geomorphological evolution of Lombok related to this eruption, especially for the eastern part of Lombok. The main goal of this paper is therefore to reconstruct the paleo-topography on the eastern part of Lombok before the eruption of the Samalas volcano in 1257 CE, and to analyse the subsequent landscape evolution following this eruption. Data were collected from more than 1300 points in order to gather geomorphological, geological, and geochemical information for the eastern part of Lombok over the last millennium. Data were obtained from wells (which are widespread in the studied area), natural outcrops (mainly cliffs along the shoreline and the rivers), and human-made outcrops in quarries, as well as from the two-dimensional resistivity profiling (Dipole-dipole array) carried out on eastern Lombok in 2016 and 2017. We estimate that 4435 ± 5.5 × 106 m3 of pumice-rich PDC, over a surface of 171 km2, buried the eastern part of Lombok in the aftermath of the 1257 CE eruption, and as a result of this rapid pumice-rich PDC deposition there has been some aggradation of the shoreline at some points, resulting in most of the pre-1257 coral reef being buried. After several intense rainfall events, the deposited volcanic material was probably eroded during the first decades following the 1257 CE eruption by mountain streams, producing lahars. We estimate that the remaining volume of pumice-rich PDC deposits following this erosion is 625 ± 5.5 × 106 m3 over a surface of 89 km2, which is equivalent to 14% of the initial volume.

Taxes are a source of enormous potential revenue. A country's collection system, both Self Assessment and Official Assessment, will greatly affect the increase in government funding receipts. One type of tax revenue is from a test assessment of corporate taxpayer compliance which will affect the assessment of tax objects objectively and professionally in accordance with assessment standards and tax provisions so that state revenues are expected to increase. The research methodology used is based on the type of qualitative research. One of the advantages of this method is that researchers can find an in-depth understanding or interpretation of a phenomenon that is happening. In addition, descriptive qualitative research is carried out by examining the literature or literature studies that focus on explaining the research results obtained, as well as by collecting data by in-depth interviews. The results of the study indicate that it is necessary to conduct a business assessment to determine the value of an object of assessment in an objective and professional manner according to assessment standards and tax regulations on going concern, including business ownership interest, transactions and everything that affects on the value of corporations, to increase state revenue because currently its implementation is not optimal.

Continuous gravity monitoring as geodetic instruments for tidal variation recording has been proving its availability for more applications. The original purpose was to monitor the changes in gravity at one local, which could be correlated to the hydrological variation and geothermal reservoir changes. Most recently explored was its relation to the events of earthquakes. We have been installing the gPhone 145 since 2016 at LIPI Campus in Bandung as a preliminary observation of the instrument. In four years of installation, the gPhone has recorded the relative gravity intermittently, interrupted only by technical problems. Temperature and pressure records indicate the instrument functions properly. However, uneven recording prevented hydrological study, in which we expected to see some changes of the gravity through the years. For earthquakes’ precursor studies, additional samples of events and time-associated gravity anomalies might give more assuring results.

Root zone geometry research is usually done in a conventional way which is destructive, time-consuming, and requires a considerable cost. Several non-destructive measurements used geophysical methods have been developed, one of which is the Electrical Resistivity Tomography (ERT) method. Tree root zone determination using ERT has been carried out in Kiara Payung area, Sumedang, West Java, with Maesopsis eminii tree as the object study. A total of 29 ERT lines were measured using dipoledipole configuration with electrodes spacing of 50 cm. The results of two-dimensional (2D) and three-dimensional (3D) inversion modeling show that the ERT method has been successfully imaging the tree root zone. The root zone is characterized as 100-700 Ωm with an elliptical shape geometry of the root plate. The root radius is estimated to be 4-5 m from the stem, the root zone diameter reaches 8-9 m at the shallow soil surface and the root zone depth is approximately 2-2.5 m. ABSTRAK Pencitraan geometri zona perakaran pohon menggunakan electrical resistivity tomography. Penelitian geometri zona perakaran biasa dilakukan dengan cara konvensional yang destruktif, memakan waktu, dan membutuhkan biaya yang tidak sedikit. Beberapa pengukuran non-destruktif menggunakan metode geofisika telah dikembangkan, salah satunya adalah metode Electrical Resistivity Tomography (ERT). Penentuan zona perakaran pohon menggunakan metode ERT telah dilakukan di daerah Kiara Payung, Sumedang, Jawa Barat, dengan pohon Maesopsis eminii sebagai objek studi. Sebanyak 29 lintasan ERT diukur menggunakan konfigurasi dipole-dipole pada dengan jarak antar elektroda 50 cm. Hasil pemodelan inversi dua dimensi (2D) dan tiga dimensi (3D) menunjukkan bahwa metode ERT telah berhasil mencitrakan zona perakaran pohon. Zona perakaran teridentifikasi berada pada nilai resistivitas 100-700 Ωm dengan root plate dan root cross-sections berbentuk elips. Radius akar diperkirakan sejauh 4-5 m dari pangkal batang, sedangkan diameter zona perakaran mencapai sekitar 8-9 m di permukaan tanah dangkal dan kedalaman zona perakaran diperkirakan antara ~2-2.5 m.

Dalam rangka mempelajari karakteristik Zona Sesar Cimandiri (ZSC), telah dilakukan pengukuran metode gravitasi di sekitar Pelabuhanratu. Kegiatan ini menghasilkan 53 data pengukuran baru dengan interval jarak 750-1500 meter (selanjutnya disebut GCG16). Untuk menggambarkan tingkat kualitas data yang dihasilkan, GCG16 dievaluasi dengan cara dibandingkan dengan dataset gravitasi skala regional dan global terpublikasi. Secara visual peta GCG16 memperlihatkan pola anomali gravitasi yang sama dengan data gravitasi regional (GRAV-P3G), model geopotensial global data satelit (EIGEN-6S2 dan GO_CONS_GCF_2_DIR_R5), serta model geopotensial global kombinasi (EGM2008 dan EIGEN-6C4). Dataset GRAV-P3G yang juga merupakan hasil pengukuran terestrial menunjukkan tingkat kesesuaian paling tinggi dengan GCG16. Sementara model potensial global kombinasi menunjukkan tingkat kesesuaian yang lebih baik jika dibandingkan dengan model geopotensial data satelit. Keenam dataset memperlihatkan pola Anomali Bouguer tinggi di bagian selatan area penelitian, mengindikasikan kontribusi dari frekuensi rendah. Variasi anomali tinggi di sekitar Sungai Cimandiri tidak teramati pada data gravitasi satelit, diinterpretasikan sebagai kontribusi dari frekuensi tinggi (berkorelasi dengan kondisi bawah permukaan lebih dangkal). Oleh karena itu untuk mempelajari struktur dangkal CFZ perlu dilakukan pemisahan anomali residual dari anomali regionalnya. Analisis First Horizontal Derivative (FHD) dan First Vertical Derivative (FVD) tidak menunjukkan kehadiran ZSC pada segmen timur GCG16, dan mengindikasikan ZSC sebagai sistem sesar yang tersegmentasi. To study the characteristics of the Cimandiri Fault Zone (CFZ), gravity method measurement has been done around Pelabuhanratu. This activity resulted in 53 new measurement data with intervals of 750-1500 meters (hereafter referred to as GCG16). To illustrate the quality level of resulted data, GCG16 was evaluated by comparing with published regional and global scale gravity datasets. Visually, GCG16 maps show the same gravity anomalies pattern with regional gravity data (GRAV-P3G), global geopotential model of satellite data (EIGEN-6S2 and GO_CONS_GCF_2_DIR_R5), as well as combined global geopotential model (EGM2008 and EIGEN-6C4). GRAV-P3G dataset, which is also a result of terrestrial measurement, shows the highest agreement level to GCG16. The six datasets show a high Bouguer Anomaly pattern in the southern part of the research area, indicating the contribution of low frequencies. High anomaly variations around the Cimandiri River were not observed in satellite gravity data and interpreted as high frequencies contribution (correlated with more superficial subsurface conditions). Therefore, to study the shallow structure of the CFZ, it is necessary to separate the residual anomaly from the regional anomaly. First Horizontal Derivative (FHD) and First Vertical Derivative (FVD) analysis do not show the presence of CFZ in the eastern segment of GCG16 and indicate that CFZ is a segmented fault system.

Daerah Karaha-Talaga Bodas, yang terletak di kawasan Utara Gunung Galunggung, Tasikmalaya diduga memiliki prospek panas bumi, dengan adanya manifestasi permukaan berupa fumarol dan mata air panas. Metode Magnetotelurik (MT) diaplikasikan untuk mengidentifikasi struktur resistivitas bawah permukaan yang terkait dengan sistem panas bumi. Pengolahan data MT dilakukan melalui beberapa tahap, yaitu transformasi Fourier , seleksi crosspower , analisis rotasi, analisis kontak vertikal dan inversi dengan hasil akhir berupa model sebaran 2D. Hasil pengolahan data menunjukan adanya lapisan konduktif dengan nilai resistivitas 1-10 Ohm.m, yang diduga berperan sebagai lapisan penudung. Zona reservoir berupa daerah dengan nilai resistivitas 10-100 Ohm.m. Nilai resistivitas yang lebih besar dari 100 Ohm.m berkorelasi dengan batuan beku yang biasa dianggap sebagai sumber panas. Interpretasi hasil pengolahan data MT diintegrasikan dengan informasi geologi untuk mendapatkan gambaran sistem Panas Bumi Karaha-Talaga Bodas . The area of Karaha-Talaga Bodas, at the north of Mount Galunggung, Tasikmalaya, was expected to have a geothermal prospect due to several surface manifestations of fumaroles and hot springs. The Magnetotelluric method (MT) was then applied in this area to identify the subsurface resistivity structure related to the geothermal system. The MT data processing included Fourier transform, crossover selection, rotation analysis, vertical contact analysis, and inversion, with the result of a 2D resistivity model. The resistivity model indicated the existence of a conductive layer with the resistivity value of 1-10 Ohm.m, which could be a caprock. The reservoir zone is the area with the resistivity value of 10-100 Ohm.m. The resistivity value greater than 100 Ohm.m correlates with the basement, that acted as the heat source. Interpretation of the MT model was then integrated with the geological information to get an overview of the Karaha-Talaga Bodas geothermal system.

The Guci and Kalipedes hot springs, in northwestern slope of Mount Slamet, Central Java appears on the contact between volcanic breccia rocks with lava flows. The hot springs is located on a structure lineament or fault, west-east trending for Kalipedes hot springs and Northwest-Southeast lineament direction for Guci hot springs. The Baturaden hot springs located at the southeast slope of Mt. Slamet appear on the contact between polimicbreccia with lava in a relatively northwest-southeast trending river valley. Breccia rocks generally have higher permeability compare to relatively impermeable lava flows. Volcanic rocks in the study area composed by olivine basalt, basaltic andesites, pyroxen andesite with fairly high potassium content or as calc alkaline basalt or andesite affinity. The presence of the main structure controlling the appearance of hot springs evidenced by radonstudies that show a high radon value to > 40 bpm/L showed high permeability that is interpreted as a weak zone due to the of the geological structure or fault activities in Kalipedes and Guci areas while in the Baturaden, the radon content is relatively low so that estimated the main control of the hotspring is permeability differences. The presence of the geological structure or the faults could be proven through magnetotelluric research. Abstrak Mata air panas Kalipedes dan Guci di lereng baratlaut Gunung Slamet, Jawa Tengah muncul pada kontak antara batuan breksi gunungapi dengan aliran lava. Mataair panas tersebut terletak pada suatu kelurusan struktur atau sesar berarah barat-timur untuk mataair panas Kalipedes dan kelurusan berarah baratlaut-tenggara untuk mataair panas Guci. Mataair panas Baturaden yang terletak di kaki tenggara G. Slamet muncul pada kontak antara breksi polimik dengan lava pada suatu lembah sungai yang berarah relatif baratlaut-tenggara. Batuan breksi umumnya memiliki tingkat kelulusan fluida yang tinggi sedangkan aliran lava relatif kedap fluida. Batuan gunungapi di daerah penelitian disusun oleh basal olivin, andesit basaltik, andesit piroksin dengan kandungan kalium cukup tinggi atau berafinitas sebagai basal atau andesit kalk alkalin. Kehadiran struktur utama pengontrol pemunculan mataair panas dibuktikan dengan penelitian gas radon yang menunjukkan nilai radon yang cukup tinggi sampai tinggi >40 dpm/L dan kelulusan fluida yang tinggi yang ditafsirkan sebagai zona lemah akibat kegiatan struktur geologi di kawasan Kalipedes dan Guci,sedangkan di daerah Baturaden nilai gas radon relatif rendah sehingga diperkirakan kontrol utama pemunculan mataair panas adalah perbedaan kesarangan batuan. Kehadiran struktur geologi atau sesar-sesar tersebut dapat dibuktikan melalui penelitian magnetotelurik.

Bandung area, as one of most populated area in Indonesia and one region with a high risk of earthquake hazard, needs a comprehensive mitigation work. To locate active faults is one of the most important things in preliminary survey for earthquake hazard mitigation effort. Accordingly, two transect lines of gravity measurement were completed across a suspected active fault, Haruman Fault, at the east of Bandung Basin region. The subsurface modeling has presented a general idea of geological subsurface structure of this transects area and indicates the possible existences of faults at the east boundary of Bandung-Garut Basin.