bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mapping vulnerability level of tsunami disaster in Coastal Villages of Pariaman City, West Sumatera
Authors: Hadi Fakhri , Damayanti Astrid 
Published: August 2019

AbstractPariaman city is one of the cities that is indicated prone to tsunami disasters because it is close to the shoreline and directly adjacent to the Indian Ocean. Coastal village of Pariaman City that faces directly to the offshore makes the coastal villages more vulnerable to tsunamis. Settlement is a residential area that must be protected, so mapping the vulnerability’s region to the tsunami that is focused on the settlements is needed to protect the residents. This study aims to map vulnerability level of settlements to tsunami disaster in the coastal village of Pariaman City. Vulnerability region is seen from exposure, sensitivity, and resilience. The data in this study are elevation, distance from shoreline, slope, distance from river, population, quality of the building, knowledge of disaster mitigation, and socialization of disaster mitigation. Each component is then overlaid with overlay techniques (scoring and weighting) of Geographic Information System (GIS) to obtain the vulnerability. The results showed that settlements in the coastal villages of Pariaman are dominated by “Low” vulnerability, followed by “Moderate” and “High” vulnerability. The “High” vulnerability levels are in low elevation, close to shorelines, low slopes, close to river, low building’s quality, high population, and no socialization.
Characteristic aquifer in volcanic terrains: case study at Caldera Lake Maninjau, West Sumatera - Indonesia
Authors: Sehabbudin Muhammad , Dianto Aan , Subehi Luki , Singgih Irianto TH 
Published: August 2019

Abstract
Lake Maninjau is a caldera lake with volcano-tectonic type. Lake Maninjau composed of andesit and tuff formation. The existence of water was sourced by rain and ground water. The aquifer units consist of local productive aquifers and rare ground water aquifer. The purpose of this research is to know the characteristic of aquifer in volcanic terrains support water stability in lake. Geoelectric measurements with Wenner configuration were obtained to know subsurface resistivity which a device used were IRES T300f, used RES2DINV software. The results showed that characteristic of aquifer divided into two areas, rare aquifer and productive aquifer. Productive aquifer with average 21.2 – 213 ohm meter, located at Tanjung Sani (elevation 462 m) had similar with Batang River (elevation 701 m). Rare aquifer with average value 48.4 – 436 ohm meter located at Hamka School (elevation 632 m) and Lawang Park with (elevation 1,294 m). The results of geoelectric reconstruction revealed that volcanic terrains around Lake Maninjau were dominated by rare groundwater aquifer, where capable to keep groundwater in small volume. Further, Fault with northwest – southeast as the general direction were considered to drain water through volcanic terrains.
Characteristics of magnetic susceptibility and geochemistry of paddy soils in Malang City, East Java
Authors: Daryanti N Y , Zulaikah S , Mufti N , Haryati D S 
Published: August 2019

Abstract
Paddy soils are a typical anthropogenic soil resource that has a wet-dry cycle and plays an important role almost all over the world, mainly in Indonesia. Along with the development of the current area of rice farming, the changes of many environmental from natural areas has undergone to settlements area and influenced by human activities. This study examines the magnetic properties and element content in special soils of paddy farming areas in the city of Malang. In this study magnetic susceptibility measurement was conducted on 60 samples taken from 3 locations, using Bartington susceptibilitymeter MS2B. The element determination was conducting by XRF (X-Ray fluorescence) on 3 representative samples. The result showed that the average of magnetic susceptibility low frequency (χlf) of paddy soils was 3.66 ×10−6 m3kg−1. The chemical elements in paddy soils are dominated by Fe, that is around 41.2 % then followed by Si about 36.7%, Al about 12%, Ca about 10.5% and Ti is the lowest value, that is about 2.13%.
Magnetic characterization of soil to determine the source origin. Case study: soil around Bromo Volcano, Tengger Volcanic Complex
Authors: Santoso N A , Syaifullah K I , Zulaikah S , Bijaksana S 
Published: August 2019

Abstract
The research on soil characteristics is very important in Indonesia. Indonesia is a well-known country for its volcanoes in the world. Many lush areas around the volcano are still active. One of the famous and still active volcanic complexes is the Tengger Volcanic Complex. The aim of this research is to analyze the magnetic characteristic of four volcanic soils around Bromo Volcano. The sample consists of soil from Gubug Glakah (GGK), Ngadirejo (NDJ), Nongko Jajar (NKJ), and Waringinanom (WAN) Village. Rock magnetism method combine with geochemical analysis are applied in this study. The results of this research are a significant difference in magnetic susceptibility value of WAN soil (1976.4 × 10−8 m3/kg) with magnetic susceptibility value of three other soils (between 900-1200 × 10−8 m3 / kg). Meanwhile, X-Ray Fluorescence (XRF) analysis showed that FeO concentration on WAN soil was lower than other soils. This indicates that the concentration of magnetite minerals (Fe3O4) on WAN soil is higher than other soils. The difference of magnetite mineral concentrations in the soil may be due to difference sources. Based on these results, it is concluded that WAN soil may not come from a similar source. This study still needs further research.
The government policy on the conservation of natural resources and ecosystems in Kuningan, Indonesia
Authors: Akhmaddhian S , Hartiwiningsih H , Handayani I GAKR , Yuhandra E , Yuhandra  , Budiman E,H , Rahmat D , Syafrudin O 
Published: August 2019

Abstract
The utilization of natural resources should consider the availability and the carrying capacity of the nature for the society’s prosperity purpose since the excessive use of natural resources can lead to any disasters. The purpose of this study is to find out and analyze the implementation of conservation policy of natural resources and ecosystems in Kuningan. The method used was mixed method and the data collection techniques were interview, observation, and literature study. The results revealed that the conservation policy of natural resources is regulated based on Law Number 5 of 1990 about The Conservation of Natural Resources and Ecosystems, and other related Regulations such as Government Regulation, Ministerial Regulation, and Regional Regulation. Further, regarding the implementation of conservation policy of natural resources and ecosystems in Kuningan, the regional government stipulated the protected forest area of Mount Ciremai to become The Mount Ciremai National Park in 2004 and created regional regulations concerning the conservation of water resources, botanical gardens, and bird’s protection. In conclusion, the implementation of conservation policy of natural resources and ecosystems in Kuningan is running well. Yet, the government’s consistency in conducting programs related to the conservation of natural resources and ecosystems becomes the future challenge.
Study on linearized inversion of surface wave dispersion for estimating near-surface shear wave velocity
Authors: Lesmana Aditya , Priyono Awali , Yudistira Tedi , Agustina Anisa 
Published: August 2019

AbstractNear-surface shear wave velocity is very important for geophysical and geotechnical engineering. The use of surface wave for characterization of the near-surface subsurface involves three steps: acquisition, extracting dispersion curve, and inversion method to generate near-surface shear wave velocity. In this study, we explored a linear inversion technique to see the effect of some parameters such as the initial model and the damping factor on the inversion results. We used the Levenberg-Marquardt algorithm and written in Matlab. Synthetic data used three-layer earth model with assumed homogeneous, isotropic, flat, and half-space. Synthetic examples demonstrated that inverted result depends on the initial model. Based on our results, we have ranged from 30% to 120% of the true model in providing the initial model. It is found that there is an asymmetry between the range of the initial model which is larger and smaller than the true model. This is due to the non-linearity of the differential equation and the solution of the Jacobian matrix using numerical approach. There are several suggestions for solving this problem: (1) using an analytical approach, (2) higher order deductions when using numerical approaches. In term damping factor, our result show range between 10−2to 1 give a stable inversion.
The fault identification by gravity and seismology in West Lembang Segment
Authors: Laesanpura Agus , Afnimar  , Dahrin Darharta , Abdurachman Dadi 
Published: August 2019

Abstract
The Lembang fault considering vulnerable because of the site is near downtown Bandung. The west Lembang segment is the rural area of Cibodas. The two opinions is emerging, become normal fault or strike slip fault, based on recent earthquake (2010 onward). The geology data show the structure is observed by the outstanding topographic extended about 20 km, with volcanic rock very dominant. The seismology data is analysed for year 2011 in Mw less than 3, and classical fault plane solution is obtained. The gravity data is better acquired than 0.1 mGal, with elevation precision better than 60 cm. The upward Continuation, and second vertical derivative, is applied on data, as well as modelling 2.5D. The section is presenting in one section only, while data is getting in larger area. The seismology data show mostly for event is strike slip although in several parts having event normal. The gravity data is not ideal as graben like structure but rather locally low about 10 mGal amplitude. The combining the two methods suggested the slip zone or sag pond is more possible for the local anomaly. Besides, the Lembang fault is extended toward north rather to west or south.
Delineation of sedimentary sub-basin and basement configuration based on the upward continuation filter and 2d and 3d modeling of gravity data (a case study: Rembang Area and its surroundings)
Authors: Muharina Gita Nia , Setiadi Imam , Santoso Budi , Supriyana Eddy 
Published: August 2019

Abstract
East Java Basin is classified as a classical back-arc basin so that it is indicated that the basin has a complex structure and stratigraphy where there is an area called Rembang High. Rembang High is a gravity anomaly term that appears in Northern of East Java Basin area which has a higher value than other physiographic zone and is assumed to be associated with Rembang anticline. It is interesting to study the basement configuration and sedimentary sub-basin presumption. The gravity anomaly is supperposition of all anomaly sources in the subsurface, namely regional and residual anomaly. The separation of regional and residual anomaly is done by using upward continuation filter. Optimum continuity height can be obtained from the cross correlation of two continuity heights. The tesidual anomaly was obtained from the difference between Bouguer and regional anomaly. In addition to use the optimum continuity height, anomalous source depth estimation is obtained by using spectral analysis. The results obtained using both upward continuation and spectral analysis shows the same optimal depth value of 3500 meters or 3.5 kilometers. 2D and 3D modeling is done to facilitate the interpretation of the condition of geological structures below the surface. The modeling result shows the existence of rocks that are raised (basement high) at a depth of 3.5 kilometers and basin depocenter at a depth of 5 kilometers with a basement which is assumed as a metasediment rock has > 2.7 g/cm3 density.
Review of time-lapse microgravity correction due to shallow groundwater variation
Authors: Pasengo Y I , Widodo L E 
Published: August 2019

Abstract
Microgravity surveys can be applied for reservoir monitoring, such as monitoring of hydrocarbon or geothermal reservoirs. One factor that needs to be corrected from gravity data in reservoir monitoring is the gravity signal due to shallow groundwater variation. The correction due to shallow groundwater effect shall be calculated from groundwater change, in this case can be measured from groundwater table change. So far, correction due to shallow groundwater variation in microgravity data is calculated against the influence of groundwater mass change in the saturated zone only, while the change of mass of groundwater in the unsaturated zone is ignored, thus giving an over-estimated correction result. The purpose of this paper is to review time-lapse microgravity correction due to shallow groundwater variation by including the influence of groundwater mass variation in the unsaturated zone. This review includes a case study using three-point piezometer groundwater data. The correction due to groundwater mass variation in the unsaturated zone is obtained by calculating the difference between the total water content at two measurements over a certain time interval. The calculation of total moisture content in the unsaturated zone is based on a soil-water retention curve that describes the relationship between moisture content and pore pressure. Considering the effect of water mass in the unsaturated zone, the total correction due to shallow groundwater variation has a smaller range, about 35% to 50% compared to the correction that only considers the effect of water mass in the saturated zone alone.
Fuzzy logic application for cave entrance identification
Authors: Pambudi Ridwan Arif , Damayanti Astrid , Marko Kuswantoro 
Published: August 2019

Abstract
Fuzzy logic allows ambiguity and obscurity. Fuzzy logic explains that truth is not an absolute way. Rather, it presents data in ranges. This becomes the advantage of fuzzy logic in categorizing spatial data in a natural way. Cave entrance identification in karst landscape has an important value because caves are the alternative water resources and conservation region for biota biodiversities, archaeological heritage, and other research for the different discipline of science. This research was conducted in Gunung Sewu Karst Landscape with varied physiography, Ponjong and Semanu District, Gunungkidul Regency. The purpose of this research is to examine the accuracy of fuzzy logic in identifying cave entrance. This research is an integration between geographic information system and remote sensing. Alos Palsar imagery is processed to produce drainage density, slope, and elevation region, while Sentinel 1 imagery processing produces lineament density. Other spatial data used in this research include monthly rainfall data and geology formation. All variables in raster format are reclassified using fuzzy membership and then overlaid with fuzzy overlay. The result is that cave entrance is found in the region with high fuzzy logic value range. Fuzzy logic has high accuracy in identifying cave entrance in Ponjong and Semanu District, Gunungkidul Regency.
The impact of season change to salt productivity in Pangenan Sub-district Cirebon Regency in 2013 and 2014
Authors: Halil Amrih 
Published: August 2019

Abstract
Salt as a commodity will always be needed by human as well as human need for food. Climatic conditions, less favorable weather changes are a natural factor that inhibits salt production. This study was conducted to analyze changes in salt productivity and salt farmer income due to seasonal changes in Pangenan Sub-district, Cirebon Regency as the largest salt producer in West Java. The variables of the research are seasonal conditions, salt production, salt pond area, salt productivity, selling price and salt farmer income, in 2013 and 2014. Variable data obtained from Fisheries and Maritime Office of Cirebon Regency, and the results of direct interviews with salt farmers then seen relation through statistical calculations using the Pearson Product Moment Correlation method. The result of the calculation shows the correlation value between the change of season and the productivity of 0.368 as r counting, r table of 0.320, and the significance of 0.023, and the value of income correlation with the number of dry months of 0.316 as r counting, r table of 0.271 and significance of 0.027 with significant correlation at 0.05 or 5%. The results show that r counting > r table and significance < significant correlation which shows the influence of seasonal changes seen from the number of dry months to productivity and income, where more and more dry months in one year, the greater productivity and income of salt farmers.
Geochemical distribution and behaviour of mercury and arsenic in the Brunei-Muara District, Brunei Darussalam
Authors: Pg Dr Karim Khairunnisa Nazirah , Norazme Nur’Aqidah , Seow Cheng Cynthia Shie , Zulkefle Nurul-Izzyani , Tsikouras Basilios 
Published: August 2019

AbstractBoth mercury and arsenic are toxic elements which can affect human health and ecosystems negatively. Monoelemental geochemical maps were constructed to identify the spatial distribution of both mercury and arsenic in Brunei Muara District of Brunei Darussalam. This paper is a product of a pilot project aiming at constructing the geochemical atlas of Brunei Darussalam. Extensive field work and sampling enabled us to collect 187 subsoil samples with a sampling density of 1 km2. Both mercury and arsenic were analyzed in the fine fraction and the relevant geochemical maps were constructed and correlated with the geological, land use and different vegetation types maps of Brunei Darussalam. Certain anomalies observed on heat maps can be linked to anthropogenic activities in industrial and urbanised areas, as well as to analyze mobility of these elements due to natural phenomena and different types of soils.
Measurements Combination of Elastic Anisotropy and Anisotropy of Magnetic Susceptibility on Case Study in Igneous Rock of Lava Flow Type from Ijen Volcanic Complex, East Java
Authors: Ndari N R D W , Bijaksana S , Nurhandoko B E B , Latief F D E 
Published: August 2019

Abstract
Research about the anisotropy parameters of rock is important for geophysical investigations. This research was a preliminary study which aims to find the relationship between elastic anisotropy and anisotropy of magnetic susceptibility in igneous rock of lava flow type with MR1 code and to interpret preferred orientation in MR1 sample based on the integration of anisotropy measurement results with the supported results from micro-computed tomography (μCT) analysis, petrography analysis and geological data analysis. This research has never been done before. This study was divided into several main stages consist of elastic anisotropy measurements on a cube-shaped specimen to determine the direction of maximum velocity and elastic anisotropy parameter values, anisotropy of magnetic susceptibility measurements on six cylindrical specimens to determine the direction of maximum susceptibility (magnetic mineral orientation) and AMS parameter values, petrography analysis on the all sides of the cube in order to observe preferred orientation in mineral and μCT analysis in a cylindrical specimen to determine the pore trend of rock. This study showed the relationship between AMS and elastic anisotropy in MR1 sample which indicated by positive correlation between the direction of maximum susceptibility and maximum velocity. Based on the results, MR1 sample has elastic anisotropy degree ranges from 2,6 % - 6,6 % for P waves and 2,2 % - 4 % for S waves and anisotropy of magnetic susceptibility degree around 2,6 % - 5,4 %. The integration of all measurement results including the direction of maximum velocity, direction of maximum susceptibility, preferred orientation in mineral, pore trend, and dip direction of sheeting joint indicate preferred orientation in MR1 sample towards NE-SW. One possible cause of such preferred orientation is the direction of the lava flow. Further studies in this topic are needed to support this hypothesis.
Coupled Hydraulic and Mechanics Finite Element Modeling of CO2 Injection into a Layered Isotropic Media Using FEHM
Authors: Haerusalam Herdis , Sahara David P. , Fatkhan  
Published: August 2019

Abstract
CO2 injection into the hydrocarbon reservoir affects the subsurface mechanics and hydraulic condition. The injection has to be performed in a way that there will be no reservoir and/or top seal failure. In such case, a simulation of the injected fluid propagation needs to be performed to see its possible impact to the top seal and existing major faults. We use finite element method to perform this injection simulation. In this research, we use open source software Finite Element Heat and Mass Transfer Code (FEHM) to simulate CO2 injection processes into reservoir. Subsurface geological model was constructed in a dimension of 3000 m (easting) x 3000 m (northing) x 2000 m (vertical). Vertically, it consists of four layers which represent upper layer (400 m), top seal (200 m), reservoir (900 m), and basement (500m). The grid around the reservoir rocks is refined to give more detail results. The open hole injection is set at 850 - 890 m depth, 1500 m easting and 1500 m northing. The material is assumed to be isotropic. The initial pressure and temperature increase as a function of depth with a pressure gradient of 0.00981 MPa/m and a temperature gradient of 0.025 degrees C/m. A vertical fault is modelled at 600 m eastern to the injection well. Injection process is carried out with 6 kg/s of CO2 injection with simulation time for ten years to see its impact to the fault. A vertical fault is The modelling results show that the CO2 injection will not reactivate the fault at 10 years.
A Resolution Enhancement of Rayleigh Wave Dispersive Imaging using Modified Phase-Shift Method
Authors: Lesmana Aditya , Priyono Awali , Yudistira Tedi 
Published: August 2019

Abstract
Multi-channel analysis of surface wave (MASW) method is an efficient tool for obtaining vertical shear wave profile. One of the key in the steps in the MASW method is generate a dispersion curves. To generate dispersion energy, the acquired shot gathers data have been transformed from the time-space (t-x) domain to the frequency-phase velocity (f-v) domain using 2D wavefield transformation so that the dispersion curve can be determined by picking the peak of dispersion energy. In this paper, we proposed a modified phase-shift method to increase the resolution of Rayleigh wave dispersive imaging so that the accuracy of the dispersion curve determination becomes higher. This method added processing step on the conventional phase-shift method. The algorithm is written in Matlab environment. We compared this method with the conventional phase-shift and frequency-wavenumber (F-K) method and applied to synthetic and real data. We used DISECA program in Matlab to generate synthetic waveforms. Our results from the synthetic and real data show that modified phase-shift method can improve the dispersion energy imaging resolution better than the conventional phase-shift and F-K method.