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The presence of geothermal manifestation in Bangka Island (Southeast Sumatra, Indonesia) with the absence of Quaternary volcanic activity and also relatively low seismicity events has raised intriguing questions on the control of the geothermal system in this area. As the regional tectonic setting of Indonesia volcanic geothermal systems has been known, that of non-volcanic geothermal systems such as radiogenic system become an issue to be investigated. This study reports the geochemistry and petrography analysis of Triassic granite related to radiogenic production at the vicinity of hot springs in Bangka Island. Surface temperatures of the Bangka hot springs range from 37 to 70.7 °C and pH values vary between 5.6 and 7.5. These hot springs are discharging either in close to massive granite bodies or occur in between two major NE-SW striking faults zones, i.e., Pemali fault and Payung fault. Our results indicate the average radiogenic heat production of Late Triassic Klabat granite in the northern area ranges from 28.5 to 38.34 μWm−3 and the southern area ranges from 28.3 to 49.5 μWm−3. In comparison to similar granite belt located in Malaysia, heat production of granitoid in Bangka hot springs is four times higher, possibly due to their different granite origins.

Different tectonic characteristics are exhibited among Maluku Sea and Banggai-Sula Microcontinent which are located side by side to each other. However, the northern part of the Banggai-Sula Microcontinent, positioned along the Maluku Sea margin, has a complex geological structure to be observed. Therefore, this study aimed to analyze the subsurface structure and sediment thickness due to extensional mechanisms in the area, using the gravity method. The investigation was executed through power spectrum analysis and three-dimensional (3D) modeling of complete Bouguer anomaly data. Eleven x-direction profiles were employed to determine the depth of the contact boundaries between the shallow and the deep discontinuities. The results showed that the deep and shallow discontinuities obtained from the 3D modeling and spectrum analysis have similar values, with depths ranging between 14.52 km and 15.14 km, as well as 1.23 km and 1.39 km, respectively. The shallow discontinuity area was dominated by sediment rocks with a 2.6 g/cm3 to 2.8 g/cm3 density. The area is interpreted as the Buya Formation superimposed by the Tanamu Formation. The deep discontinuity area with a depth of up to 16 km. We found areas of high density (density value is >3 g/cm3) adjacent to low rock density (density value is 2 g/cm3 to 2.3 g/cm3). The observed are interpreted as fault-bounded formations of terrestrial conglomerates and sandstones from the Bobong Formation. These formations are located within a half-graben and are found to rest unconformably on the basement towards the southern onshore region.

Islam and the Relation of Religions in the Perspective of Hadith and Its Implementation in Educational Institutions As a pluralistic country consisting of various diverse backgrounds, Indonesia can potentially lead to horizontal conflicts if not managed properly. This article discusses the relationship between Islam and religions, which has become an issue throughout humanity's history. Descriptive research uses the takhrij hadith method and traces information sourced from books and journals that find the topics studied. In editorial terms, some traditions show an accommodative relationship between Islam and other religions, but some seem discriminatory. Thus, there are fluctuations and dynamics of relations between Islam and other religions, with nuances of harmony and disharmony. Therefore, there needs to be a reading of the hadiths constructively implemented in education as a conducive place for teaching Islam multicultural values

Resistivity meter is a tool used to measure the resistivity of a medium or material by injecting a current into the earth. The main circuit contained in the resistivity meter is a current source, current meter, voltage meter, and data viewer. The current source is part of an electrical device that functions to conduct electric current. In this case, the constant current application is needed in resistivity measurement because the medium to be measured is the earth. There is a layer of earth rock which causes the instability of the current when it is injected into the earth. This study aims to design a current and voltage meter with a constant current source based on Arduino nano using a Shunt Resistor and ADS1115 as a current and voltage meter. The results of several tests showed that the constant current source circuit can be applied to the current variations of 1.9 mA, 12.5 mA, 18.4 mA, 62.5 mA, 83 mA, and 125 mA. This constant current variation can work on a resistance value of 20 Ω to 680 Ω. The application of constant current sources to current and voltage measurements is successful at a constant current variation of 1.9 mA with a variation of resistance from 4.7 Ohm to 1 MOhm.

This research used qualitative phenomenology. The data were collected by interview and documentary techniques. Determination of informants using purposive sampling consisting of the chairman, secretary, and practitioner members who are members of Jam’iyah Ruqyah Aswaja (JRA). The data obtained was analyzed directly and interpreted by the stages of presenting text, messages, instructions, and information. The research results reveal that; (1) there are six syifa verses contained in the Qur'an that can heal people who are sick. The syifa verses are found in the Quran letter At-Taubah (9) :14, Fussilat (41): 44, Yunus (10) :57, An-Nahl (16) : 69, Al-Israa (17): 82, and Asy-Syu'araa (26): 80, (2) Hadith and atsar friends related to the syifa verses contained in the hadith of the book of Bukhari number 5301 and 5309. Based on the path of transmission, the two traditions are agreed to be true traditions even though in the text there are differences but in meaning it has the same substance and (3) Treatment of ruqyah using syifa verses is carried out by reciting verses of the Quran and blowing it to the patient and through the medium of water.

Candi Palgading yang terletak di Desa Sinduharjo, Ngaglik, Sleman, D.I.Yogyakarta tanggal 1 Juli 2009 sampai 4 Juli 2009 dengan menggunakan alat Resistivitymeter. Pemetaan ini bertujuan untuk mengetahui penyebaran dan kedalaman batuan penyusun candi pada Situs Candi Palgading serta sebagai sumber informasi bagi usaha penemuan benda-benda purbakala yang terpendam dalam tanah. Pengambilan data dilakukan dengan menggunakan 8 lintasan ukur, dan mencakup luas daerah pengukuran ±1000 m2. Lintasan 1, 2, 3, 4, 5, 6 dan 8 mengambil jarak rentang elektroda (a = 3 m) sedangkan lintasan 7 jarak rentang elektrodanya (a = 2 m). Keseluruhan lintasan menggunakan n = 1 sampai dengan n = 7. Pengolahan data menggunakan software Res2dinv dan surfer. Nilai resistivitas yang digunakan untuk menentukan batuan penyusun candi adalah nilai resistivitas batu andesit. Hasilnya menunjukkan profil nilai resistivitas batuan penyusun candi 750 Ohm-m sampai 5000 Ohm-m yang berada hingga kedalaman rata-rata 4,5 m sebagai batu andesit. Terdapat 7 lokasi yang diduga merupakan batu andesit penyusun Candi Palgading sedangkan salah satu lokasi yang lain merupakan batuan andesit bukan penyusun candi. Batuan candi pada ketujuh lokasi tersebut salah satunya telah tersingkap yakni di lokasi 4 sedangkan lokasi yang lain batuan candinya masih terpendam.

In early 2017, the geothermal system in the Suli and Tulehu areas of Ambon (Indonesia) was investigated using a gravity gradient tensor and analytic signal. The gravity gradient tensor and analytic signal were obtained through forward modeling based on a rectangular prism. It was applied to complete Bouguer anomaly data over the study area by using Fast Fourier Transform (FFT). The analysis was conducted to enhance the geological structure like faults as a pathway of geothermal fluid circulation that is not visible on the surface because it is covered by sediment. The complete Bouguer anomaly ranges of 93 mGal up to 105 mGal decrease from the southwest in Suli to the northeast in Tulehu. A high gravity anomaly indicates a strong magmatic intrusion below the Suli region. The gravity anomalies decrease occurs in the Eriwakang mountain and most of Tulehu, and it is associated with a coral limestone. The lower gravity anomalies are located in the north to the northeast part of Tulehu are associated with alluvium. The residual anomaly shows that the drill well TLU-01 and geothermal manifestations along with the Banda, and Banda-Hatuasa faults are associated with lowest gravity anomaly (negative zone). The gravity gradient tensor simulation and an analytic signal of Suli and Tulehu give more detailed information about the geological features. The gzz component allows accurate description of the shape structures, especially the Banda fault associated with a zero value. This result will be useful as a geophysical constraint to subsurface modeling according to gravity gradient inversion over the area.

The northern part of Pemalang City consists of Quaternary deposits, having the potential for earthquake amplification effect. This amplification effect amplifies the ground shaking because of an earthquake (the local site effect) that has the potential to cause damage. This study investigated the amplification factor from the HVSR curve of microtremor measurements due to soil response based on ground shear strain, the risk level of the earthquake based on peak ground acceleration (PGA), and earthquake intensity. The microtremor data from five locations in Pemalang were used to calculate the amplification factor and predominant frequency. The damaging earthquake parameters around Java during 2010-2020 were used to calculate the PGA. The microtremor data were processed using the HVSR method, and PGA was calculated using the Kanai equation. The HVSR result shows that Pemalang has an amplification factor ranging from 6.23 to 19.59 and ground shear strain varying between 0.86 x 10-4 and 6.67 x 10-4, which shows that Pemalang only experiences the vibration when an earthquake occurs. The PGA results using the Kanai equation (19.71-54.56 gal) were included in the low vulnerability category, and MMI earthquake intensity (3.08-4.70) was included in the felt earthquake category (II SIG BMKG scale). Therefore, the amplification factor from the HVSR curve of microtremor measurement, ranging from 6.23 to 19.59, showed low soil response and low-risk vulnerability based on the damaging earthquake parameter around Java during 2010-2020. [ABSTRACT FROM AUTHOR]

The demand for increased voltage in renewable energy sources is relatively high. This study examines the rapid development of technology considering the use of voltage-increasing transformers. Voltage regulator circuits are generally used to stabilize the output voltage of the rectifier according to the amount of input from the transformer. However, components for highvoltage stabilizer circuits are rare, which becomes an obstacle to the stabilization of the rectifier output. This study aimed to determine the performance of the designed rectifier circuit against a non-center tap step-up direct current (DC) 400 V transformer and compare the measurement results to manual calculations. The research method is a direct comparison between the input and output voltage values of the transformer after going through a rectifier circuit. This experiment was conducted using the repeatability method three to five times for each voltage variation on the transformer. The voltage variations successfully created are 0 to 50, 0 to 100, 0 to 200, and 0 to 400 V. The output test results from the DC transformer and rectifier circuit show linear results and an increase in peak-to-peak voltage data between the transformer and rectifier outputs by 3.8%. [ABSTRACT FROM AUTHOR]

Radiogenic heat production (RHP) has been investigated from wide types of rocks based on regional setting and metamorphism grade. In this study, we analyze the abundance of heatproducing elements (U, Th, K) and Radiogenic Heat Production (RHP) on I-type and S-type granite rocks in Bangka Island, one of the main provinces in Tin Belt Island. The average U, Th, and K concentrations for both S-type and I-types granite are 10.27 ppm, 79.6 ppm, 3.1%, and 87.79 ppm, 99.2 ppm, and 1.93 % respectively. The highest concentration of U (681.22 ppm) and Th (99.2 ppm) are found in Pangkal Pinang and K (3.79%) in West Bangka. We analyze that the RHP average for I-type granite is higher at 27.87 (N=17, range from 12.97 to 550.28) than S-type with 8.43 (N=11, range from 4.93 to 12.64). The Th/U ratio shows an exponential correlation with RHP and classifies S-type granite tectonic discriminant as continental collision and I-type granite as a continental arc. [ABSTRACT FROM AUTHOR]

Ambon and Seram islands in eastern Indonesia are located in the convergence zone of three major plates, causing this area to have many geothermal manifestations on the surface. A subsurface geological study on Ambon and Seram has been conducted based on the integration of gravity and magnetic inversion modeling to determine the intrusion of igneous rock as a potential source of geothermal energy. The gravity and magnetic inversion utilized gravity and magnetic anomaly data from the World Gravity Map (WGM) and the Earth Magnetic Anomaly Grid (EMAG), as well as the CRUST 1.0 global earth crust model, as the constraints. In general, gravity and magnetic anomalies in the study area are compatible, in which the southern part of Ambon is dominated by high anomalies and the northern part is covered by low anomalies associated with the Seram trench. The high anomaly is thought to be related to the intrusion of igneous rocks underneath the surface that have cooling and are rich in magnetic minerals, while the low anomaly is related to the destruction zone due to subduction in the north of Seram. The gravity inversion shows the distribution of subsurface rock density ranging from 1.86 g cm-3 to 2.82 g cm-3, while magnetic inversion produces rock susceptibility contrast ranging from -0.0034 SI to 0.0058 SI. Based on Curie point depth analysis of magnetic data, the bottom depth of the magnetic source is estimated at 25 km. The 3D subsurface model of Ambon and Seram based on gravity and magnetic inversion shows a massive and evident intrusion pattern with high rock density and susceptibility contrast down to a depth of 10 km. The distribution of high density and susceptibility is thought to have implications for geothermal resources in Ambon and Seram. [ABSTRACT FROM AUTHOR]

Resistivity geoelectrical method is a method to determine the value of rock resistivity. The measuring tool for resistivity geoelectrical method is a resistivity meter. One of the important features in designing resistivity meter is providing the constant current for various types of resistive loads. The difference on rocks resistance values is caused by the factor of rock types, temperature, and mineral composition. This research is aimed at designing and analyzing a set of constant current source applied at a circuit of current measurement tool based on LM324. To deal with this problem, five variations of current source were built as well as tested. The research shows the constant current was successfully built with five constant current variations with voltage 30V and tested on the loads of 56 Ohm to 1000 KOhm. The test on integrated constant current circuit measurement, and voltage worked properly on resistance (22 - 46000) Ohm. [ABSTRACT FROM AUTHOR]

In early 2017, the geothermal system in the Suli and Tulehu areas of Ambon (Indonesia) was investigated using a gravity gradient tensor and analytic signal. The gravity gradient tensor and analytic signal were obtained through forward modeling based on a rectangular prism. It was applied to complete Bouguer anomaly data over the study area by using Fast Fourier Transform (FFT). The analysis was conducted to enhance the geological structure like faults as a pathway of geothermal fluid circulation that is not visible on the surface because it is covered by sediment. The complete Bouguer anomaly ranges of 93 mGal up to 105 mGal decrease from the southwest in Suli to the northeast in Tulehu. A high gravity anomaly indicates a strong magmatic intrusion below the Suli region. The gravity anomalies decrease occurs in the Eriwakang mountain and most of Tulehu, and it is associated with a coral limestone. The lower gravity anomalies are located in the north to the northeast part of Tulehu are associated with alluvium. The residual anomaly shows that the drill well TLU-01 and geothermal manifestations along with the Banda, and Banda-Hatuasa faults are associated with lowest gravity anomaly (negative zone). The gravity gradient tensor simulation and an analytic signal of Suli and Tulehu give more detailed information about the geological features. The gzz component allows accurate description of the shape structures, especially the Banda fault associated with a zero value. This result will be useful as a geophysical constraint to subsurface modeling according to gravity gradient inversion over the area. [ABSTRACT FROM AUTHOR]

In the tourism area of Goa Kiskendo, Jatimulyo Village, district Girimulyo of Kulonprogo, Yogyakarta province which is quite popular for naturally cave tourist destination. In November 2017, there was a landslide that broke the transportation route to the Goa Kiskendo, Yogyakarta-Central Java province tourism area. Based on the Center of Volcanology for Disaster and Geological Mitigation map of soil movement in Girimulyo district, Jatimulyo Village is in the medium to high-risk movement zone. To anticipate aftershocks of a landslide in the same area, it is necessary to map areas that are potentially landslide occurs. For mapping, this area, the geophysical surveys using resistivity method with dipole-dipole configuration and electromagnetic very low frequency (VLF) resistivity mode were conducted in Goa Kiskendo area to identify the slip surface based on the contrast resistivity value. From the results of resistivity data processing, and 3D visualization it is obtained a contrast of different resistance values consist of two layers. The first layer, which is in the range of 10 Ωm-79 Ωm, is identified as soil and the second layer, which is in the range of 0,15 Ωm- 10 Ωm is interpreted as water saturated limestone. Water saturated limestone is identified as the slip surface or bedrock in the depth of 3 m - 25 m, and the soil movement when the landslide occurs, the materials will move from the north to southeastward. [ABSTRACT FROM AUTHOR]

The 4D gravity or time lapse gravity has been used many reseracher to identify fluid injection in oil reservoir. The objective of this study is to find the better way in interpreting 4D gravity anomaly due to fluid injection around the reservoir. Radial Derivatives are derivative values of gravity anomalies against horizontal distances in the radial direction. Radial inversion is a two-dimensional inversion of lines with radial directions resulting in a 3-dimension model. Time lapse microgravity research have been performed in "X Oil Field" with amount of 604 data point covering area of 4000 m x 5000 m. This Radial derivative and Radial inversion have been aplied at an injection well of the X oil field. The yield show that 4D gravity anomaly value due to injection is 0.02 mGal to 0.36 mGal. Radial derivative value in the area is 0 micro Gal/cm to 0,012 mGal/meter. Radial inversion shows radius of fluid front movement is 304 meters to 1120 meters. Radial derivative and Radial inversion have been proven fairly good to identify injected fluid movement in the reservoir. [ABSTRACT FROM AUTHOR]

Semi-infinite slab modeling has been made through inverse data gravity using Matlab. Inversion of gravity data is done by first determining the simulation data. Forward modeling uses simulation data to produce an initial guess inversion model expressed with parameters n0 (1), n0 (2), n0 (3) and n0 (4). The forward modeling is performed on the next initial guess that the value of the misfit is as small as possible through an iteration using the Jacobian matrix. Accuracy of inversion results is determined by the initial guess and the number of iterations. The results obtained show that inversion modeling is more valid in the inversion modeling process compared to advanced modeling, because the value of the parameters sought is generated from mathematical observations of the observation data. Guesses greatly affect the results of inversions obtained. Initial guesses are given in the form of parameters n0 (1), n0 (2), n0 (3) and n0 (4). The initial guess for the parameters n0 (1), and n0 (2) that are made far deviant does not affect inversion. The initial guess for the parameters n0 (3), and n0 (4) that are made deviating far influences the inversion caused by a very small RCON value so that the result is NAN