bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of changes mangrove areas toward shoreline changes in East Coast of Surabaya 2004-2017
Authors: Chairani C , Saraswati R , Shidiq I P A
Published: August 2019

Changes in the mangrove area is the crucial cause for the shoreline changes, it happens since that vegetation stores sediments which lead to accretion and if that vegetation is reduced or damaged, it will cause abrasion. This research aims to identify the changes in the mangrove area and the shoreline of the east coast of Surabaya (Purmabaya) during 2004-2017. This research uses Landsat image 7 ETM + and Landsat image 8 OLI by applying overlay method which is spatial analyzed. During 2004-2017, there was a reduction on mangrove area for 167,701 Ha and the width was increasing for 374,183 Ha. At the same time, there was an abrasion for 12,1 Ha and an accretion for 314,661 Ha. In Kalisari, the widest accretion was 233,833 Ha which was followed by the increasing width of the mangrove area, while in Keputih had the widest abrasion, 6,87 Ha. The conclusion is the changes of the mangrove area Purmabaya keep increasing likewise the shoreline changes, especially the accretion width or the increasing width which keep changing during 13 years (2004-2017).
The analysis of the need and availability of green open based on the oxygen demand in Depok City, West Java, Indonesia
Authors: Dianovita  , Siwi S E
Published: August 2019

The increase of population in Depok from 2015 to 2017 is from 2,106,000 people to 2,254,513 people. The population growth will impact the increasing needs of land built. One of the ecology function of green open space is as a producer of oxygen. This study is calculates the needs for green open space based on the oxygen requirements of two variables, the need for human oxygen and motorized vehicles. Then calculate the area and distribution of green open space from the SPOT image using the NDVI algorithm. Analize the availability of green open space requirements based on oxygen demands. The result with the increasing number of population and motorized vehicles, more green open space must be prepared in the city. Observation of green open space and distribution in Depok was carried out from 2015 – 2017, to find out the balance between the availability of green open space and the increase of population and motorized vehicles. The result of this study provide the advise for the government regarding the Minister of Public Works Regulation No. 5 of 2008 about Guidelines for the Provisions and Use of Green Open Space.
Run-out distribution of debris-flow materials: case study from some Java landslides
Authors: Sadisun Imam A. , Kartiko Rendy D. , Dinata Indra A.
Published: August 2019

Indonesia is a risk prone country from landslide disasters. The occurrence of landslides followed by the debris flow often make a lot of casualties and very terrible destructions. Accordingly, debris flow modeling of some Java landslides has been conducted in this study to determine run-out distribution characteristics of the debris materials. The concept of debris flow modeling is based on the equations of momentum, continuation, riverbed deformation, erosion/deposition and riverbed shearing stress. From this modeling, it has been indicated the best fit simulation results. In this case, run-out distributions of Pacet landslide at Mojokerto, December 12, 2002 has been properly modeled with a scenario of 0.4 viscosity value for around 5 minutes. At Sijeruk landslide, Banjarnegara, January 4, 2006 run-out distributions have been modeled using viscosity value of 0.45 for 14 minutes 51 seconds. Meanwhile, the modeling for Tenjolaya landslide at southern Bandung, February 23, 2010 with viscosity value of 0.38 shows time needed for debris materials to reach depositional area is estimated for around 12 minutes 37 seconds. From this study, debris flow modeling had given better understandings regarding flow track, velocity and distribution of debris materials from some debris flows in Java.
The Spread Of Dry Area Based On TVDI Index (Temperature Vegetation Dryness Index)
Authors: Aisyah A , Kusratmoko E , Wibowo A
Published: August 2019

This research explains the use of Remote Sensing to know which areas are dry that are connected by the morphological characteristics in the Sukaresmi district. The purpose of this research is to see the spread of the dry areas in Sukaresmi district which are vulnerable towards drought when the dry season comes using the Remote Sensing application. The Landsat image 8 OLI was used throughout July-September 2013 and between June-August 2017. One of the methods that used in Remote Sensing is triangulation. This method is known as TVDI (Temperature Vegetation Dryness Index) which consists of NDVI (Normalized Difference Vegetation Index), LST (Land Surface Temperature) with the algorithm formula of (LST–LSTmin)/(a+b*NDVI–LSTmin) that used in determining the dry areas in Sukaresmi district. The relation between the spatial pattern of the dry areas and the morphological characteristics of an area analyzed statistically. This research concludes that the spatial pattern of the dry areas in Sukaresmi district based on the TVDI method reached the highest rate of drought in September 2013 with 163.26 ha, and the drought in June 2017 with a whopping 336.43 ha. The drought areas usually concentrated on the morphological characteristics of the soil of the inhabitants, rice fields, and inclination of the slopes.
Constructing total suspended solid modelling on Agathis Lake by employing resource modelling associates program
Authors: Prastica R M S , Soeryantono H , Marthanty D R
Published: August 2019

This research uses Resource Modelling Associate (RMA) program to conduct a two-dimension model of Agathis Lake to analyse velocity and sediment transport distribution. The main programs are RMA-10 for velocity distribution and RMA-11 for the pollutant distribution. The sediment transport focuses on total suspended solids (TSS) pollutant. The research aims to construct total suspended solid model. Firstly, RMA Generation produces mesh of Agathis Lake. Next, RMA-10 and RMA-11 would perform both velocity and TSS simulation model to represent the actual condition. This research still gives temporary result due to limited sampling data. Calibration analysis of the model is needed to make the result of the program more accurate and more representative to the real condition.
Abrasion and accresion at West of Buleleng subdistrict’s coastal area, Bali (case study: Gerokgak Regency, Seririt Regency, Banjar Regency, and Buleleng Regency)
Authors: Putera Indrawan I Nyoman , Damayanti Astrid , Rustanto Andry
Published: August 2019

Gerokgak, Seririt, Banjar, and Buleleng coastal areas are located in the west of Buleleng Regency, Bali. These area are prone to abrasion and accretion. Abrasion and accresion is a natural phenomenon that’s runs balanced. Human factor caused this phenomenon were change the balanced, it causes harm to humans. The purpose of the research were to analyze influece of abrasion and accresion toward land use wide at coastal area. The research used Landsat 5, 7, and 8 images with 3 periods which were 1990 and 1997, 1997 and 2007, and the last period was 2007 and 2017. The data were processed by calculate long, width, and wide of coastline change inter period. It were relate with wide’s land use change at coastal area. The result showed that abrasion and accresion were happen along the coastal areas in research area. The worst abrasion were located in Gerokgak Subdistrict with extensive 217.109 m2 One of it’s impact are some ponds and buildings around the Segara temple at Gerokgak Village’s were destroyed.
Modification of natural waterway shape as a river trash interceptor–an approach model for Citarum River recovery
Authors: Suryaningsih Sri , Hidayat Sahrul , Sunardi
Published: August 2019

The Citarum River is the most polluted river in Indonesia. The river irrigates three cascade reservoir such as Saguling, Cirata and Jatiluhur, which serve for hydroelectric power plant, drinking water, agricultural irrigation and fishery. Solid municipal waste and agricultural debris that is dumped into the river cause destruction of river habitats, flooding and shallowing especially in cascade reservoirs. This study aims to develop an idea of river recovery from waste, by using namely river trash interceptor (RTI) located at the Citarum river tributaries due to the economic consideration and efficiency. By using CFD (Computational Fluid Dynamics) and Particle Tracing module, the form of the interceptor is simulated based on the mostly general form of the Citarum River waterway; straight line shape, bend shape and U-type shape. The parameters used are river depth, river width, water discharge, particle size and density. These results of this study could be used as a reference for decision makers and developers on further development of the RTI in the near future.
Thermal model of lava in Mt. Agung during December 2017 episodes derived from Integrated SENTINEL 2A and ASTER remote sensing datasets
Authors: Aufaristama M , Hoskuldsson A , Jonsdottir I , Ulfarsson M O , Erlangga I G D , Thordarson T
Published: August 2019

In the beginning of December 2017, Mt. Agung eruption powered down to minor ash emissions and on the middle of December, aerial photographs of the crater were taken by Indonesia Centre of Volcanology and Geological Hazard Mitigation (PVMBG) showing a steadily growing lava occupying approximately one third of the crater. 3D digital elevation model (DEM) of crater were created by PVMBG during and before the eruption, corresponded to lava volume around 2 x 10−2 km3 has been filled the crater. Here we present a method for deriving thermal model within the lava during eruption on 8 and 9 December 2017 using observations from multi infrared satellite SENTINEL 2A and Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER). We use Thermal Eruption Index (TEI) based on the Shortwave infrared (SWIR) on SENTINEL 2A and Thermal Infrared (TIR) on ASTER, allowing us to differentiate thermal domain within the lava. This study has successfully produced model of sub-pixel temperature (Th), radiant flux (Φrad) and crust thickness model of lava (Δh). The subpixel temperature and radiant flux during the eruption is in the range 655 to 975 °C and 179 MW respectively. The crust thickness model of the lava in the range of 9 to 14 m and the total volume of lava crust during this period is estimated at 3 x 10−3 km3. The combination of infrared satellite remote sensing data shows a potential for fast and efficient classification of difference thermal domains and derive thermal model of lava.
GIS Application and Remote Sensing for Monitoring the Changing of Coral Reefs in Belitung Regency
Authors: Sari P R , Saraswati R , Wibowo A
Published: August 2019

Coral reefs are one of the most important and the most vulnerable marine ecosystem in the world. The coral reefs can be damaged, because of environmental factors and human activities, such as overfishing and polluted activities. Bangka Belitung islands are one of the provinces in Indonesia that have a huge potential of coral reefs, which are likely being damaged. This study aims to analyze the changing of coral reefs that occurred in the islands of tourist destinations in Belitung Regency from 2005 to 2018. This study used Landsat satellite imageries such as Landsat 5 TM for 2005, Landsat 7 ETM+ for 2011, and Landsat 8 OLI/TIRS for 2018. In this study, the changes of coral reefs will be determined by image data processing. Then, overlay methods are used to analyze the changes. In 2005, the coral reefs had an area of 4.68 km2, but in 2011, the coral reefs area changed to 2.45 km2. Then, in 2018, coral reefs have changed to 2.04 km2. In the year of 2005 and 2011, the area of coral reefs has decreased around 2.23 km2. While in 2011 and 2018, the area of coral reefs has decreased around 0.41 km2.
Remote sensing and GIS for land conservation: identification of post-tin mining land conservation in Perimping Sub Watershed
Authors: Erthalia Meike , Supriatna  , Damayanti Astrid
Published: August 2019

Perimping sub-watershed is part of a mayor watershed in Bangka Regency where the expansion of tin mining was very high since 2001. However, this watershed still categorized as Priority II which mean it has to be maintained and retained for any changes. Environmental management program such as land conservation of post-tin mining area was contributed to maintained the condition around watershed which damaged by mining activity. This study aimed to identify the distribution of post-tin land conservation in Perimping sub-watershed based on land surface temperature and NDVI data in term of 2001, 2009, and 2017. Landsat 5 TM and Landsat 8 OLI/TIRS were used to estimate LST and NDVI. Google Earth imagery also used to identify the landcover change of land conservation. The result showed the average of LST around post-tin mining area were decreasing from high in 2001 (31°C-35°C) to moderate in 2017 (26°C-30°C). Yet the NDVI showed enhancement trend from low (0.1-0.25) to high (0.51-0.70). Both LST and NDVI distributed in the centre of Sub Perimping Watershed Area which indicate that the density of vegetation cover around post-tin area is increasing as the result of post-tin land reclamation and revegetation program.
Spatial Dynamics Model of Land Availability and Mount Merapi Disaster-Prone Areas in Sleman Regency, Yogyakarta Special Region Province
Authors: Novia Utami Nabila Dety , Supriatna  , Anggrahita Hayuning
Published: August 2019

The existence of Mount Merapi in Sleman Regency makes the agricultural land in the area fertile and that becomes the attraction for humans to occupy the region. A high population growth will lead to the residents demand of the availability built-up land higher, that makes the environmental carrying cappacity in Sleman Regency decrease. However, the volcanic activity of Mount Merapi becomes a threat to the people who live in the area of Disaster Prone Areas of Mount Merapi. Predictions on the availability of land as well as the relation to the disaster-prone areas, and the carrying capacity of the environment needs to be done. 2007 – 2017 population data and Landsat 7 ETM + 2007, 2012, and Landsat 8 OLI 2017 imagery will be used in this research as variable in the spatial dynamics model. Meanwhile, physical and accesibility data such as slope, distance from the river, distance from protected area, distance from road, and distance from the center of economic growth will be used as limiting factor of built-up land. Environmental carrying capacity can be observed through a dynamic system model of the relationship between population growth and land availability within the period of 2007 - 2100, then made into the spatial dynamics model to know it’s spatial stance. The results of this model show that built-up land increasing every year, packed areas that are suitable for built-up land first, then encroach on areas which not suitable for built-up land and Mount-Merapi Disaster-Prone Areas.
Controlling factors of underground river system of karst region in Pacitan Regency, East Java
Authors: Bahri A S , Hardyani P V , Utama W , Hilyah A , Purwanto M S , Fajar M H M
Published: August 2019

One of the interesting karst areas is the Pegunungan Sewu, because of the existence of an underground river system that developed below it. The underground river system of Bribin in Gunung Kidul, Yogyakarta is one of the evidence found by previous researchers. In Pacitan District there are karst landscapes that have not been widely studied. Pacitan karst area is in the eastern part of the karst area of Pegunungan Sewu. As the characteristics of the karst region in general, in the Pacitan karst region, there are small hills, vertical hole, closed depressions, rough and pointed surface outcrops, stalactites and stalagmites, and the presence of muddy and water sources. The Pacitan karst area is similar to the Gunung Kidul karst area which has an underground river system. However, the development of underground river systems from these two regions is thought to be different. The purpose of this study is to analyze typical and the controlling factors that influence the development of underground river systems in the Pacitan karst area, East Java. This research was conducted using VES (Vertical Electrical Sounding). The results showed that the typical underground river system that develops in the area of research is more shallow than in Gunung Kidul and suspected to be in the Vadose and it is controlled by the movement of water from the incoming surface through rock fractures.
Contact angle measurement of fluid with salinity variation on sandstone rock surface
Authors: Winardhi C W , Fauzi U
Published: August 2019

Interaction between fluids and solid surfaces plays important roles in many fields, e.g.: enhanced oil recovery (EOR), environmental engineering, agriculture, materials, etc. Research on this topic is intensively carried out by many researchers. In this research, a simple experimental setup for fluid contact angle measurement is constructed using an optical microscope and video camera with 29 frames per second. Measurement of contact angle of fluid with variation of salinity, i.e.: 1M, 2M, 3M, 4M, and 5M is carried out by recording a single droplet placed on a rock surface. Each frame of the recorded video are then analysed using image processing technique to detect the edge and calculate the contact angle. A single 8th order polynomial was applied to the edge of the wetting type droplet, but two types of polynomial fitting curves are applied for edge of non-wetting type droplet. It is obtained that on preparatory glass, the higher the molarity, the longer the droplet will evaporated. On the sandstone surface, fluid contact angle on sandstone surface is about 80° and decreases with time with different trend of decrement. This may be due to complex interaction between fluid and pores at sandstone surface spot.
Clay minerals in the sediments as useful paleoclimate proxy: Lake Sentarum case study, West Kalimantan, Indonesia
Authors: Dianto A , Subehi L , Ridwansyah I , Hantoro W S
Published: August 2019

Lake Sentarum is a flood-plains lake that will dry and flood as climate cycle that is interesting to be studied climate change from the past to near the present. The objective of this study is to reveals paleoclimate conditions by analysing clay minerals that present in the lake sediments. The study investigated clay mineral in lake sediments from 70 cm long core, X-RD analysis was obtained to identify various of clay minerals. The clay minerals of Lake Sentarum comprises of illite, chlorite, and kaolinite. The relative change in abundance of clay minerals indicating climate conditions, besides numbers of chemistry and crystallinity of illite represents weathering mechanism. Our research reveals that climate history of Lake Sentarum from sediments core began cold and arid climate episode. This episode was characterized by low value of illite chemistry and illite crystallinity were 0.37-0.41 and 0.19°Δ2θ-0.2°Δ2θ, respectively, and slight decrease abundance of kaolinite. There was no significant changes until the middle of the sediments core. Significant changes of abundance of kaolinite and illite chemistry occurred in top of the core. The percentage of kaolinite and illite chemistry became the highest value that reflected strong chemical weathering occurred in the watershed with warm and high rainfall climate conditions.
Geometric tortuosity analysis of porous medium using simple neurite tracer
Authors: Amien Muhammad Nashih , Pantouw Genki Tanod , Juliust Hessel , Eljabbar Latief Fourier Dzar
Published: August 2019

The concept of tortuosity is used to measure and characterize the structure of porous media. Geometric tortuosity is the ratio between the shortest pathway in the medium to the distance between the inlet and outlet plane. Simple Neurite Tracer method is used to track the connected pores by tracing the tube structures of pores in 3D image stacks. In this analysis, the method is directly applied to the pore structure itself as well as the skeleton of the pores which represent the essential structure of the pore. The method is applied to four simple models of pores with different complexity levels, both the actual pore structure and the skeleton, to determine the effect of complexity to the tortuosity. The analysis is the applied on a digital sample of porous rock model with the size of 256 × 256 pixels. The interconnected pore for both the actual pore structure and the skeleton representation is traced by the Simple Neurite Tracer method. It was observed that the skeleton is a good representation of the actual pore because the pattern of tortuosity obtained between this two approaches are very similar. For all synthetic samples, the more complex the pore structure, the greater the tortuosity.
Implementation of overlap degree in sphere packed sedimentary rock model and its impact to pore structure characteristics
Authors: Latief Fourier D E , Pantouw Genki T , Wongkaren Hessel J , Amien Nashih
Published: August 2019

Computerized rock modelling is studied and developed because natural rock samples can sometimes be difficult and expensive to obtain. Sedimentary rock modelling is a process of generating a digital sedimentary rock model using numerical methods which resembles the ideas and processes of natural sedimentary rock formation. One of the most important physical characteristics in generating the model is how the pore structure is affected by overlap degree among each grain. The overlap degree simulates the output of compaction process in natural sedimentary rock formation. The approach to implement such idea is by using spherical grains so that the degree of overlap could exactly be determined quantitatively. Stochastic method is used in the algorithm to map each grain positions based on a desired range of overlap degree. From previous trials it shows that higher overlap degree produces lower porosity. The algorithm is implemented in generating two dimensional cross sections of the model as well as in generating three-dimensional structure. Characteristics of pore structure are analyzed for various modelling parameters to obtain better understanding of the modelling nature.
Determination of chemical elements that controlling magnetic susceptibility of cacao farming soil in Koting A Sikka Nusa Tenggara Timur
Authors: Zulaikah S , Rosalina E R , Suaidi dan D A , Agustine E
Published: August 2019

Koting A in Sikka is one of the most popular and productive agricultural cacao areas in Nusa Tenggara Timur. The area was selected in this study with the aim of understanding the soil magnetic properties that is suitable for cocoa farming. This study assessed the magnetic susceptibility and chemical element content of cocoa farms soils. Magnetic susceptibility was measured by Bartington MS2B on 72 samples taken from 8000 m2 farming area, whereas the determination of chemical elements was done by XRF test on 3 representative samples. The results showed that the magnetic susceptibility of low frequency χlf has a range between (12-20) × 10−6m3kg−1 and the soils contains some dominant elements of Fe about 37%, Al 7 – 8%, Ca 11 -12%, Si 29-32%, Ti of about 2% and nickel 3 - 4%.
The stage of tourism object development in Bantul Regency, Special Region of Yogyakarta, Indonesia
Authors: Darajat Akhmad Shidiq , Susilowati M H Dewi
Published: August 2019

Bantul Regency has many tourism objects potentials such as nature tourism and cultural tourism. The objective of research was the correlation between the stage of tourism object development and type of attractions, landform. The method used are the spatial and statistical analysis (chi-square). Research variables include the number of visitors, primary facilities, secondary facilities, conditional facilities, accessibility, commercialization, and promotion. The results showed the stage of tourism object development in Bantul Regency included on involvement stage, development stage, and consolidation stage. Result of statistical analysis showed; (1) the correlation between the stage of tourism object development and type of attraction was not significant at the significance level (α) = 0.05; (2) the correlation between landform and the stage of tourism object development was not significant at the significance level (α) = 0.05, which means that the stage of tourism object development in Bantul Regency are not always on the right type of attraction and landform.
Assessing of economic losses in landslide affected areas in Cibanteng Village, Cianjur District, West Java
Authors: Abidin F G , Kusratmoko E , Susiloningtyas D
Published: August 2019

Indonesia is one country that has a high incidence of natural disasters. Among the various types of disasters, landslides are one of the most common hydrometeorological disasters. One of the areas that have a high rate of landslide disaster is Cianjur district, West Java province. Assessing of economic loss due to landslide disaster in a region is one of the important tools in the recovery and reconstruction framework. The purpose of this research was to asses the indirect losses of three areas affected by landslide in Cibanteng Village, Cianjur district, West Java. In this study, the UAV (unmanned aerial vehicles) was used to create high-resolution maps of areas affected by landslide. Participatory mapping was conducted to delineate damaged land use areas and then interviewed the farmers to obtain information about the agriculture activities. The results of this study showed that the amount of indirect losses in the three location reached Rp 352,811,700 (US $ 25,200) at the landslide occurance and Rp 1,205,152,300 (US $86,082) for the indirect losses in 2.5 years. This value can be a reference for assessing indirect losses in other areas.
Identification of stakeholder involvement in the conduct of corporate social responsibility (CSR)
Authors: Santoso M B , Raharjo S T , Apsari N C , Wibhawa B
Published: August 2019

The awareness of companies involved in community’s live by corporate social responsibility (CSR) activities is elevating, because of the regulation and the willingness of the companies to be involved in creating sustainable development. The conduct of the CSR is socially constructed according to the companies context, does not creating dependency and creating a natural proces of separation toward the collective independent of the community. Identifying the involvement of stakeholders in the conduct of CSR will serve as important information in understanding the degree of the involvement. The study is using descriptive analysis with qualitative approach. The data collection used are in depth interview, focus group discussion, and literature study. The research shows that identifying the quality of actor within the community serve as the foundation for stakeholder involvement, in addressing social, economical and environmental aspects issues. The mindset, awareness and communication style serve as supportive factor for group cohesiveness and continuity in the CSR activities. This research claims that the importance of the CSR activity is not depend on the amount of assistance provided, but on how the assistance lead the community to elevate their social quality degree toward self-actualization community resulting independency and sustainability.
Post-flood handling pattern by self-sufficient community in Garut
Authors: Sjoraida D F , Anwar R K , Rahman M T
Published: August 2019

This study discusses the process of restoring post-flood soil functions with self-sufficient community activities in Garut, West Java, Indonesia. The soil restoration is conducted based on the aspirations of the community. This study used a qualitative approach to obtain natural settings of which many behaviors and events occur during the recovery period. This study also uses institutional theory, because it can guide researchers on institutional structures, regulations and procedures that can have a significant impact on the good of the community. The study finds that performing their functions as elected organizers; they always prioritize the interests of the people in their activities. To achieve that, the managers of the organization, comprehend and collect the aspirations of the community; accommodate and follow up aspirations and complaints; create events together with the society and give moral encouragement to rise from adversity. The study also found many events leading to soil maintenance to prevent future damage.
Feasibility study of rainwater conservation and harvesting for industrial community in North Jakarta
Authors: Murdiana A W , Soesilo TEB , Bismo S
Published: August 2019

Rainwater harvesting has been adopted in many regions of the world when raw water supplies are insufficient for the community. A multinational company engaged in heavy equipment around North Jakarta has a rainwater pool facility that can be used to anticipate flooding during the rainy season using the Ground Catchment System method. In addition, this water source can be used to meet the company’s clean water needs both for industrial and domestic needs and to reduce the use of municipal supply water (Perusahaan Daerah Air Minum, PDAM). This study aims to meet the needs of clean water, anticipate floods and droughts. This research uses a problem-solving approach to reduce the use of water from PDAM. The variables studied in this research are average water quantity, water quality, and reduction of water consumption from PDAM by replacing it with clean water from rainwater, and then assess them using qualitative and quantitative method for six months. The results concluded that the quantity of water from rainwater treatment produced during six months of research can reduce the consumption of PDAM water as much as 20%. In general, the rainwater harvesting for the needs of the industrial community in the company can be considered as a feasible solution to provide clean water substitute and to reduce PDAM water consumption.
MBBR technology for water treatment east flood canal as a raw water source of DKI Jakarta
Authors: Pradafitri W S , Moersidik S S , Abdini C
Published: August 2019

Population growth increases the need for raw water supplies. Poor quality, quantity, and continuity of raw water conditions impacts to the scarcity. The problem can be solved by water treatment technology. East Flood Canal (BKT) is one of the infrastructure facilities in DKI Jakarta province has potential to become a source of raw water supply. This study aims to analyze the appropriate pre-processing technology to improve the water quality of BKT. Analytical Hierarchy Process method was used to determine the appropriate pre-treatment technology to improve the water quality of BKT. There are 3 alternative technology options, such as MBBR (Moving Bed Biofilm Reactor), MBR (Membrane Bioreactor), and Bank Filtration, while the criteria are the environment, social, and economic. The questionnaire were weighted, reviewed consistently, and analyzed descriptively. The results showed that the MBBR technology earns the highest weight of 0.51, MBR is 0.38, and the BF is 0.12. Based on environmental and social aspect, MBBR needs the smallest area, hence it can be easily approved by the people. In economic aspect, the investment of MBBR is more expensive, however the operational is affordable. In conclusion, MBBR technology is the most appropriate technology for water treatment of East Flood Canal.
Identification of aquifer using geoelectric resistivity method of reciprocal schlumberger array (case study: Tanggamus, Lampung Province)
Authors: Santoso Budy , Prirahmayang Natasya , Kirana Kartika Hajar
Published: August 2019

Tanggamus district known as an area indicated to have a potential aquifer layer because there are many areas of groundwater infiltration. This study aims to obtain the depth of aquifer layer and aquifer type found in Tanggamus area. This research was carried out using geoelectric resistivity method of reciprocal Schlumberger array. Based on the results of data processing in correlated with geological data, aquifer layer is identified in rough sand rocks with resistivity value 35-100 Ωm. The confined aquifer layer lies at a depth of 20.6-136 m in the measuring lines of 3, 4 and 5. The unconfined aquifer layer lies at a depth of 1.71-151 m in the measuring line of 1. The leaked aquifer layer lies at a depth of 2-169 m in lines 2 and 5. The characteristics of the layers of rock consists of sandstone as an aquifer, breccia as an aquifuge and tuff as an aquiclude.
FK-filter and radon transform methods comparative study on 2D pre-stack migration gather of Kangean Waters data
Authors: Panjaitan Raymond J.T. , Agustine Eleonora , Rosandi Yudi , Nainggolan Tumpal B.
Published: August 2019

The main problem in marine seismic exploration are multiples. Multiple is coherent noise appeared by the difference of impedance between water and seabed layer which is lead to secondary reflection wave acts as new reflector source point. Multiple appearance in seismic cross section can cause misinterpretation so multiple attenuation is required. Both F-K Filter and Radon Transform methods can be used to attenuate multiple by isolating signal and noise data. Both methods have similarity in domain transform, F-K Filter transforms offset (x) - time (t) domain to frequency (f) - wavenumber (K) and Radon Transform operates in τ-ρ domain to separate moveout between signal and noise. Both mehods are applied on 2D marine seismic data on Kangean waters shallow depth 200-500 meter. Radon Transform shows better result on attenuating multiple compare to F-K Filter on migrated cross section line L09 and L16. Multiple attenuation increases signal to ratio (SNR) of both line L09 and L16 which lead to more accurate in interpretation.
A field test and performance evaluation of accelerated weight drop (awd250 v1.0) for shallow seismic survey
Authors: Bahar Alfian , Fatkhan  , Rachmat Sule M.
Published: August 2019

The acquisition of seismic reflection involves generating and recording seismic wave field on/near the surface of the earth. Success of producing high quality seismic data depend on choice of seismic sources. There are commonly seismic sources for land seismic surveys such as explosive sources, vibrators and Accelerated Weight Drop (AWD). In some cases, the use of explosive sources often faces many problems, especially related to the costs, permission and environmental issues. The use of vibrators is also similar, facing problems such as the availability of access roads, permits and the environment impact. The use of AWD seems to be a solution as an alternative seismic sources when explosive or vibroseis cannot be used for some reasons. In this research, we have designed and built a mechanical seismic source named AWD250V1.0. This hand-made AWD prototype was developed for shallow seismic surveys. To evaluate the performance of this tool and to improve the design of the prototype, a field tests have been carried out. The test was conducted in Ciparay village, Bandung Regency, West Java. The survey area is mostly paddy field with the near surface covered by clay and highly seismic attenuation. The purposes is simply whether AWD can work properly or not while maintaining data quality and safety standards. In addition, the test is intended to find out how deep penetration of seismic waves using this source. Seismic recorders used were 96 channels with interval between receivers was 10 meters. Findings showed that the deepest reflection can be seen around 450 millisecond or approximately 400 meters. To sum up, the device is work well and is able to produce good quality of seismic sources. The prototype can also meet design criteria that are repeatability, portability, economical and environmetal friendly.
Modeling of subsurface based on gravity data with second vertical derivative (SVD) and euler deconvolution optimazitation
Authors: Soleha Kania Pinasti , Handyarso Accep , Fitriani Dini , Supriyana Eddy
Published: August 2019

The purpose of this study is to estimated the mean depth of bedrock in the Sahul Basin and identification of subsurface geological of the research area. The study contucted in Sahul Basin, which is associated with a basins in Papua New Guinea that has been proven to produce oil and gas, with the adjacent geographical location, is expected to have the same play concept. The analysis that used in this research is Second Vertical Derivative (SVD) to know the geological structure, Euler Deconvolution to get depth solution, and Forward Modelling 2D for information of the subsurface. The results of the study have shown that the average depth of bedrock is more than 3500 meters, and structur that developed of the research area are strike slip fault, normal fault, and reverse fault, that occured due to the compression force between Australian Continental Plate and Pacific Ocean Plate.
Gravity analysis to estimate the mud stream direction in porong by applying the delaunay approach
Authors: Putra M I , Hidayah A N , Septiana L A E S , Supriyana E
Published: August 2019

Lumpur Lapindo eruption at Porong, Sidoarjo is still continuing, it is suspected triggered by the flow of high-pressure mud. Measurements were performed for analyzing the subsurface structure where there was subsidence of soil and mudflow in the affected areas of Lumpur Lapindo with gravity method. The results of gravity data measurements are not always regular according to planning due to unpredictable field conditions. Therefore in this research writer used geostatistics method in interpolation of gravity anomaly data. Second Vertical Derivative (SVD) is a method used to determine the fault structure. The gravity anomaly value in the Porong area is 8 mgal to -32 mgal. High-value gravity anomalies in the northwest region with the highest anomaly value of 8 mgal indicates an increased of mass density and soil degradation. While the gravity anomaly of low value in the northeastern region with the lowest anomaly is -34 mgal which indicates a decrease in subsurface mass density. The fracture structure that has been obtained can be used to determine the direction of Sidoarjo mud movement.
Landslide investigation using self potential method and electrical resistivity tomography (Pasanggrahan, South Sumedang, Indonesia)
Authors: Santoso Budy , Hasanah Mia Uswatun , Setianto
Published: August 2019

Landslide is a geological event that occurs because the movement of slope-forming material in the form of soil, rock or combination of material type to a lower place due to the influence of gravity. The trigger factor of landslide in Pasanggrahan, South Sumedang, Indonesia is the increase of water content in the slope and the slip plane. The slip plane began to actively to turn on when the rainy season arrives. The infiltration of rainwater into slopes as an avalanche trigger can be detected by Self Potential (SP) method. SP measurements were performed to determine changes in subsurface water flow. SP data acquisition using fixed base technique and leap frog technique. The rocks in the research area that serve as the slip plane are clays associated with Volcanic Breccia. One of the geophysical methods that can identify the slip plane is the Electrical Resistivity Tomography Method. The ERT method can detect slip plane based on rock resistivity. Based on the local geology that has been correlated with the value of Self Potential and Electrical Resistivity Tomography, the following results are obtained: water table : (1 - 13) Ohm.m and SP value : (16 - 50) mV, clay : (72 - 100) Ohm.m and volcanic breccia: (171 - 550) Ohm.m.
Erosion rate prediction model ssing SWAT and CA-Markov methods (case study: Upper Ci Catih Catchment Area)
Authors: Ramadhan Kurniawan , Supriatna
Published: August 2019

Landuse has a vital role that affects the movement of water on hidrological cycle. Around Upper Ci Catih Catchment Area in the past 10 years, many of various industries (ranging from smal-scale to large-scale industries) have increased. Increasing built-up area, especially settlements and industries can increase runoff that have an impact on land degradation such as erosion. This study focuses on the hydrological modelling made by SWAT (Soil Water Assesment Tools) and landuse change prediction using CA-Markov (Cellular Automata-Markov Chain) to find the effects of landuse changes on the erosion rate changes. Erosion rate prediction in 2032 based on landuse changes prediction in that year. This study shows that variations of Hydrologic Response Unit (HRU) conditions affects the erosion rate in every subwatershed. The result of accuracy and calibration test satisfied, which NS and R2 mark for SWAT validation is 0,56 and 0,72, and kappa coefficient value for CA-Markov model validation by 89%. The changes of landuse especially forest and irrigated rice fields is predicted in 2032 will decrease in every Subbasin. It will affect the increase of average erosion rate in every Subbasin by 15% of the erosion rate in 2017 on Upper Ci Catih Catchment Area.
Modelling cellular automata for the development of settlement area Bengkulu City
Authors: Pratami M , Susiloningtyas D , Supriatna
Published: August 2019

Population and development activity increasing push will demand higher settlements. Population density is low and becomes higher along with population growth rate and leads to centralization of settlements in certain sub-districts that will shape the dispersion pattern of settlements. The research method used in this research is Cellular Automata Modeling and Geographic Information System. The purpose of this research to identify the pattern of distribution of settlements based on population density in 2032 in Bengkulu city. The results show that the pattern of settlement distribution in the western part of Bengkulu city has high Density level and distribution pattern of clustering settlements while the North-East-South has medium to low density of population and distribution pattern of random settlement.
Semivariogram fitting based on SVM and GPR for DEM interpolation
Authors: Setiyoko A , Arymurthy A M , Basaruddin T , Arief R
Published: August 2019

DEM (Digital Elevation Model) as a digital model of the earth’s surface elevation could be generated from remote sensing technology such as stereo imaging for various applications. To generate DEM from stereo imagery, interpolation or approximation process stage is required. Stochastic interpolation e.g. ordinary kriging uses semivariogram fitting to calculate weights of interpolation values based on known points. This research is applying regression types of machine learning for semivariogram fitting to interpolate DEM. Previous research conducted was LS-SVM (Least Square-Support Vector Machine) and SVR (Support Vector Regression) for semivariogram fitting process. Types of SVM and GPR (Gaussian Process Regression) are adopted for semivariogram fitting for ordinary kriging interpolation in this experiment. The result showed that in general SVM types could predict accuracy better than other types of regression, and GPR types produce better DEM accuracy based on the experiment.
Delineating a low velocity zone using joint inversion of rayleigh-wave dispersion curve
Authors: Rubaiyn Al , Priyono Awali , Safani Jamhir
Published: August 2019

Seismic methods widely used to study the shallow subsurface for different purposes. Analysis of P-wave refraction cannot uniquely determine the seismic velocities as a function of depth when a low velocity layer is present. It is situation commonly encountered in geotechnical site investigation. Utilization of Rayleigh wave dispersion can be uses to determine the structure with existence of low velocity zone. In this study, we discuss efficiency and effectiveness of a joint inversion of Rayleigh wave dispersion curve which combining the genetic algorithm and the Occam’s algorithm to delineate a low velocity zone. Numerical test is presented. The shear wave velocity and thickness errors which is the difference between the true and inverted model parameters is used to appraise the value accuracy inversion model. The result provides accurate solution models with is 2.3 % and is 13.4%. Finally, we demonstrates the joint inversion scheme to invert Rayleigh wave dispersion curve which calculated by phase-shift method from a real example data.
The preliminary results of Lindu software: a free seismological data processing using python framework
Authors: Styawan Yudha , Andika Putu Pradnya , Suhendi Cahli , Firdaus Ruhul , Sudibyo Maria R P , Erlangga I F , Ry Rexha Verdhora
Published: August 2019

LINDU software is developed to solve integrated earthquake data processing. It is GUI based software that fulfil the needed for user friendly type of software. The Python framework is used for computation and visualization and integrates the common programs for earthquake data processing, such as GAD.exe, JHD.exe, and HypoDD.exe. It is also integrates the common procedure of routine data processing in earthquake seismology and works in local and regional scale. In this paper, we shows the preliminary results of LINDU software for several functions. To identify arrival time of P-wave we employ Akaike Information Criterion (AIC), MER (Modified Energy Ratio) and S/L Kurt’s method. The results of these method will be considered as guided – auto picking. However, the results also can be treated as reference for picking manually with Seisgram2k.jar. Geiger’s method is employed to locate the event location. The events can be relocated and 1D velocity can be updated by employing Joint Hypocenter Determination (JHD). The next method to relocate the event location is Double Difference (DD) algorithm. The precision result of Lindu software has been tested using IRIS and real data available which run seamlessly.
The potential of landslide in Lake Maninjau Catchment Area, West Sumatra
Authors: Raden Ayu Ramanda RS , Noor Djauhari , Ridwansyah Iwan
Published: August 2019

West Sumatra is amongst tectonically and volcanically active area, located at the interface of Indo-Australia and Eurasia plates. The movement of plates triggers many natural disasters, one of them is landslides. Especially Lake Maninjau that located in Tanjungraya District, Agam Regency, West Sumatra that often experience the landslide. This landslide caused physical damage and loss of life. The direct research was conducted in the field by mapping rock types, soil types, slope and then other factors such as rainfall and landuse, using Geographic Information System (GIS) based analysis using the weighted method with spatial analysis, and weighting for each parameter. The higher score and the weight, then the effect will be higher on the ground movement and vice versa. The purpose of this research is to get information about potential of landslide as the basis for the development of Lake Maninjau Watershed Area. Based on the result of DEM analysis the research area is dominated by a fairly steep slope (15%-30%) whereas the area with flat slope – very flat only 20% of 244,03 km2. Landuse as settlement, plantation, forest, water etc. Result of this research with spatial analysis is potential of ground motion in 20 locations with steep slopes around Koto Malintang Village and Tanjung Sani Village. The validation of calculation result shows 75% similarity with field data.