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Journal : Journal of Applied Geology

Bio-geochemical simulation for solute transport in Piyungan landfill, Yogyakarta Special Province, Indonesia Keophousone Phonhalath; Dwikorita Karnawati; Heru Hendrayana; Doni Prakasa Eka Putra; Kenji Jinno
Journal of Applied Geology Vol 3, No 1 (2011)
Publisher : Geological Engineering Department Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (4270.715 KB) | DOI: 10.22146/jag.7159

Abstract

Piyungan Landfill is the largest in Bantul Regency. According to water quality sampling taken from a leachate pond, there are significant contaminant issues resulting from landfill leachate. The objectives of this research were achieved by applying a two-dimensional bacteria mediated reduction numerical model was applied. Method of characteristic was applied to solve the advection part of the solute transport equation. Three bacteria (X1, X2, and X3) groups were defined in the redox model. In the conceptual model, bacterial X1 utilizes oxygen under aerobic conditions and nitrate, NO-3 under aerobic conditions as electron acceptors. Consequently, under aerobic conditions bacteria X2, and X3 utilize MnO2, and Fe(OH)3 respectively as electron acceptors. In the redox model organic carbon which was defined as CH2O was considered as the electron donor for all bacteria mediated reduction reactions. The results of research are to improve the understanding of biogeochemical processes in aquifer.
Batch Studies On Arsenic Adsorption Onto Lignite, Bentonite, Shale And Iron Sand: Effects Of Ph, Time, Particle Size And Sulfate Concentration Kyu Kyu Mar; Dwikorita Karnawati; Doni Prakasa Eka Putra; Sarto Sarto; Toshifumi Igarashi; Carlito Baltazar Tabelin
Journal of Applied Geology Vol 4, No 2 (2012)
Publisher : Geological Engineering Department Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2253.952 KB) | DOI: 10.22146/jag.7197

Abstract

Arsenic (As) is a toxic element found in both natural and anthropogenic sources. High concentration of this element was recently uncovered in the groundwater of Sumbawa Island, Indonesia. To mitigate this problem, As adsorption potential of natural geological materials like lignite, bentonite, shale, and iron sand obtained in Indonesia were evaluated by batch experiments. Arsenic adsorption onto these materials was investigated as a function of solution pH, particle sizes of adsorbents and coexisting sulfate concentration. In addition, batch leaching experiments were performed to elucidate the stability of geogenic As present in all adsorbents at different pHs. The results showed that among these natural materials tested, lignite was the most effective adsorbent of As(V) followed by bentonite, shale and then iron sand, and that the amounts of As(III) adsorbed onto all adsorbents were lower than those of As(V).This indicates that As(III) is more mobile in comparison to As(V). The adsorption isotherms of As(III) and As(V) conformed to nonlinear types, either Langmuir or Freundlich. It was found that adsorption of As onto these natural adsorbents was pH-dependent. This could be attributed to the changes in the surface charges of the adsorbents with pH. With respect to the adsorbent particle size, the amount adsorbed somewhat increased with decreasing particle size, which could be explained by the larger surface area of the smaller particles. Acidic (pH < 6) and alkaline (pH >10) conditions destabilized the geogenic As content of the adsorbents, indicating that the effectiveness of these natural materials as adsorbents is greatly limited by the pH of the contaminated system. Keywords: Adsorption, arsenic, natural geological materials, particle size, pH
Copper Mobility Assessment Using Speciation Schemes: Case Study–Mantrijeron District, Yogyakarta, Indonesia Phetnakhone Xaixongdeth; Heru Hendrayana; Doni Prakasa Eka Putra; Dwikorita Karnawati; Tsutomu Sato
Journal of Applied Geology Vol 4, No 2 (2012)
Publisher : Geological Engineering Department Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2403.502 KB) | DOI: 10.22146/jag.7198

Abstract

factors such physical and chemical properties, especially mineralogical composition of such environment. This study focused on the mineralogical of two soils types (fine sandy loam and loamy fine sand) to retain/mobile Cu. Two non contaminated soils from Yogyakarta urban area, Indonesia, were artificially contaminated with Cu solution. Subsequently, soils artificially contaminated were extracted from various geochemical phases of soil by sequential extraction procedure. The results show that both of soils types can retain Cu well with maximum is 5.8 mg/g of loamy fine sand and 3.9mg/g of fine sandy loam. Additionally, the iron amorphous phase content in clay fraction is influence Cu retains in these soils. This is advantage in environment of Yogyakarta urban area, Indonesia, where this area underlain by loamy sand soil. Keywords: Copper, mobility, iron, sequential extraction.
ESTIMATION OF THE GEOLOGICAL STRENGTH INDEX SYSTEM FOR CAVITY LIMESTONE LAYER IN QUARRY AREA, REMBANG, CENTRAL JAVA PROVINCE, INDONESIA R. Andy Erwin Wijaya; Dwikorita Karnawati; Srijono Srijono; Wahyu Wilopo
Journal of Applied Geology Vol 5, No 2 (2013)
Publisher : Geological Engineering Department Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (13738.293 KB) | DOI: 10.22146/jag.7209

Abstract

Limestone mining needs a good mine design which is safe for the environment. Mine design is determined by the rock mass quality. The rock mass quality in each mine location is not necessary the same depending on the geological conditions. The research area is located in limestone quarry of Sale District, Rembang Regency, Center Java Province-Indonesia. In the limestone quarry area, there is cavity zone which consists of cavity limestone layer at the wall of quarry bench. This cavity layer in limestone quarry has occurred by solution process. The cavity layer zone is a potentially weak zone which has caused bench failures in the limestone quarry area. The objective of this research is to analyze the rock mass quality in the cavity limestone layer using Geological Strength Index (GSI) system. Final result of the research is a rock mass characterization, specifically for cavity limestone layer. Keywords: geological strength index, limestone, cavity layer
DETERMINATION OF NUCLEAR POWER PLANT SITE IN WEST BANGKA BASED ON ROCK MASS RATING AND GEOLOGICAL STRENGTH INDEX Irvani Irvani; Wahyu Wilopo; Dwikorita Karnawati
Journal of Applied Geology Vol 5, No 2 (2013)
Publisher : Geological Engineering Department Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (859.231 KB) | DOI: 10.22146/jag.7210

Abstract

Indonesian government through the National Atomic Energy Agency has planned to build a nuclear power plant. One of the proposed sites is in West Bangka Regency, Bangka Belitung Archipelago Province. The engineering geology of this area is, however, not fully understood and requires further investigations. Engineering geology investigations were carried out by assessing the rock mass quality and bearing capacity based on field observation and drilling data. The assessment was conducted using Rock Mass Rating (RMR) and Geological Strength Index (GSI) classification. The rock mass in the study area was divided into four units, namely Units of Sandstone, Granite, Mudstone and Pebbly Sandstone. The RMR and GSI values in the study area are influenced by the parameters of discontinuity space density, the slope of discontinuity orientation, grade of weathering and groundwater conditions. The assessment shows that the Granite Unit has the best quality which is shown by the average RMR value of 53 and GSI value of 66. Based on the average RMR value, the Granite Unit is estimated to have cohesion value between 0.2 and 0.3 MPa, friction angle between 25° and 35°, and allowable bearing pressure between 280 and 135 T/m2. Based on the GSI value, the Granite Unit is estimated to have uniaxial compressive strength value between 1.0465 and 183.8 MPa, tensile strength between (-0.0122) and (-5.2625) MPa, rock mass strength values between 24.5244 and 220.351 MPa, and modulus of deformation within a range of 1.73–86.68 GPa. The Granite Unit is considered to be the most appropriate location for the nuclear power plants. Keywords: Nuclear power plant foundation, geological strength index, rock mass rating, rock mass quality
ROCK MASS RATING OF CAVITY LIMESTONE LAYER IN REMBANG, CENTRAL JAVA, INDONESIA R. Andy Erwin Wijaya; Dwikorita Karnawati; Srijono Srijono; Wahyu Wilopo
Journal of Applied Geology Vol 6, No 1 (2014)
Publisher : Geological Engineering Department Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (15999.055 KB) | DOI: 10.22146/jag.7214

Abstract

mine design. Mine design is determined by the rock mass quality, which varies from one mine location to another, depending on the geological conditions. The research area is located in limestone quarry of Sale District, Rembang Regency, Central Java Province, Indonesia. In the study area, a cavity zone is exposed at the wall of quarry bench and occurs by a solution process. The cavity layer zone is a weak zone which has caused bench failures. The objective of this research is to evaluate the quality of the cavity limestone layer for a safe mine design using Rock Mass Rating (RMR) system. Final result of the research is a rock mass characterization, specifically for the cavity limestone layer. Keywords: Rock mass rating, limestone, cavity layer
SUMMARY OF RESEARCH WORK ON THE EVALUATION ON LONG TERM STABILITY OF ARTIFICIAL SLOPE PROTECTION Ros Soty; Dwikorita Karnawati; Kenji Aoki
Journal of Applied Geology Vol 1, No 2 (2009)
Publisher : Geological Engineering Department Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1703.67 KB) | DOI: 10.22146/jag.7226

Abstract

Application of GPR, RedExplorer1.4 and GeoStudio2004 have been used to evaluate the overall stability condition of a steep slope along Kalibawang irrigation channel km 8.5, Kulon Progo Regency, Yogyakarta Special Province, Indonesia, that this slope slid down in 1990 and was restabilized by cut to be gentler and covered by shotcrete. Topographic map and engineering geological map in scale 1:2000 have been established prior to the detail investigation. Three drilling logs with in-situ test, SPT and CPT, and samplings have been made and sent to soil mechanic laboratory for index properties tests, and a slope profile along the main axe will be also created for stability analysis through GeoStudio2004. Moreover, GPR has been used to run on a full slope surface to detect the distribution of fractures and/or cavities behind the shotcrete and the results have been interpreted by the aid of RedExplorer1.4.Three profiles showing the rate and depth of fractures and/or cavities are established whereas the slope stability analysis through GeoStudio2004 is the next target of the research. The author is expecting the result from the integration of GPR interpretation and GeoStudio2004 to figure out the overall stability with respect to its existing conditions and its own geometry. Keywords: GPR, GeoStudio2004, overall stability, fracture and/or cavities.
PALEOSTRESS ANALYSIS TO INTERPRET THE LANDSLIDE MECHANISM: A CASE STUDY IN PARANGTRITIS, YOGYAKARTA Salahuddin Husein; Ignatius Sudarno; Subagyo Pramumijoyo; Dwikorita Karnawati
Journal of Applied Geology Vol 2, No 2 (2010)
Publisher : Geological Engineering Department Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3334.175 KB) | DOI: 10.22146/jag.7251

Abstract

Paleostress analysis on the landslide boundary faults is able to explain the sliding mechanism. This method is particularly useful to study a paleolandslide. About 30 striated fault planes from the Parangtritis paleo-landslide, located in the Yogyakarta coastline, were analyzed to define their principle stress axes. The eastern boundary fault, named as the Girijati Fault, was the main fault responsible for the mass movement and leaving a considerable steep cliff. It moved normal in a left lateral sense with ENE – WSW extension and dragged the rockmass southward, creating a NNW – SSW extension along the Parangtritis Fault and turn it into the western boundary fault. The rockmass slided along the stratigraphic contact between the underlying Nglanggran Formation and the overlying Wonosari Formation, created a semi-circular crown cliff as the northern boundary and produced some isolated topographic highs of the thrust block near the toe. Keywords: Paleostress, landslide boundary, fault, paleolandslide
Engineering geology evaluation for predicting the collapse susceptibility of Sidoarjo hot mud earth levees: A hazard assessment Doni Prakasa Eka Putra; Juwarso Juwarso; Dwikorita Karnawati
Journal of Applied Geology Vol 2, No 2 (2010)
Publisher : Geological Engineering Department Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22146/jag.7252

Abstract

Since May 29, 2006, a sea of hot mud has been gushing from the ground in Sidoarjo, East Java, 35 kilometres south of Indonesia’s second largest city, Surabaya. Due to this disaster, approximately thousand of peoples have been forced from their homes because 600 ha of land and villages were submerged, farmland was ruined, businesses and schools closed as the mud inundated the surrounding area. The authorities response was to build containment ‘basins’ or ‘ponds’ by enclosing areas of land within earth dams, or levees. During the heavy rain on the rainy season, the earth dams and ringdykes have overflown and broken regularly, causing the flooding of more land and damaging infrastructures. However, not only in the rainy season, the levees had also collapses during the dry season. Therefore, an engineering geology study was conducted in order to evaluate the geological factors which causes this phenomena. The parameters used for the evaluation are the heterogeniety of lithology under the dams, geological discontinuity which indicated by the occuring of surface cracks and bubbles, and subsidence phenomena which indicated by the vertical displacement. Overlying method was used to build homogeniety zone of engineering geology based on those parameters, and the resulted map was once again overlay with the location of dams collapses. Result of this evaluation shows that the earth dams collapses were highly correlated with the existing geological discontinuities and subsidences, respectively. Based on this study, the susceptible location of earth dams collapses can be predicted and allow engineers to prepare and plan better engineering solution for the high probable collapses points in order to protect land and infrastructures from the damaging hot mud overflown. Keywords: Hot mud disaster, geological factors, homogeniety zone, earth levee failure points, Sidoarjo-Indonesia
Mineralogical and Geochemical Control of Altered Andesitic Tuff upon Debris Slide Occurences at Pelangan Area, Southern Mountain of Lombok Island, Indonesia Dwi Winarti; Dwikorita Karnawati; Hary Christady Hardiyatmo; Srijono Srijono
Journal of Applied Geology Vol 1, No 1 (2016)
Publisher : Geological Engineering Department Universitas Gadjah Mada

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (2054.489 KB) | DOI: 10.22146/jag.26953

Abstract

Debris slides were recently found in the Pelangan area at Southern Mountain of Lombok Island, Indonesia. Pelangan is well known as the gold mineralization and hydrothermal alteration area. This study is aimed to identify the mineralogy and geochemistry of altered andesitic tuff that controlled slope instability and induced debris slides. For this purpose, it is necessary to prepare the field observation and laboratory analyses. Landslide inventory reveals that the Pelangan debris slides mostly occur in altered andesitic tuff. Based on the outcrop observations in the field, andesitic tuff found around the Pelangan debris slides have been altered in general. The strong intensity of alteration developed by hydrothermal alteration in this study area produces large amount of clay minerals especially montmorillonite, kaolinite, and illite. The abundance of those clay minerals reflect the intermediate argillic alteration. Montmorillonite is a type of clay mineral that easily swells at wet condition and easily shrinkages at dry condition. Swelling of clay mineral destroys intersheet and interlayer bonds, and reduces shear strength. The presence of clay minerals in the altered andesitic tuff of intermediate argillic zone can be considered as one of the factors that induced to the Pelangan debris slides. Further studies on geotechnical and slope stability analysis of the landslide area are crucial to be done for better understanding of the characteristics of the altered rocks inducing hazardous landslides.