bluuebunny/crossref_metadata_2025 huggingface dataset:
Can the court bridge the gap? Public perception of economic vs. generational inequalities in climate change mitigation policies
Authors: Schönhage Nanna Lauritz , Wieland Theresa , Bellani Luna , Spilker Gabriele
Published: July 2024

Climate change and most climate policies affect and reinforce different forms of inequalities. For instance, climate change policies that aim to change consumer behavior by increasing the price tag of goods and services that cause carbon emissions often carry a disproportionately higher burden (in terms of financial cost) to those with lower incomes. They can thereby either exacerbate existing income inequalities or contribute to generating new ones. Meanwhile, refraining from engaging with climate mitigation policies will incur other detrimental societal costs: the financial burden and the harmful consequences of climate change that future generations will have to bear if nothing is done. In this paper, we examine how the immediate economic inequality citizens face from climate mitigation policies (regarding carbon taxation) weighs against the long-term generational inequalities future generations will experience. We study how both types of inequality relate to policy support for climate change mitigation policies in the context of Germany. The German case is of special interest because a recent court ruling of the Federal Constitutional Court allows us to test whether making people aware of a new legal reality can bridge the gap between the economic and generational inequality. Our findings using a between-subjects survey experiment fielded among German citizens (N = 6,319) in 2022 show that immediate economic concerns trump future generational concerns, generally making citizens less supportive of the policy. This negative support is however somewhat mitigated by the supportive signal from the court ruling.
Comparison of the vs30 model and site class based on MASW, microtremor and N-SPT data in the Opak River Basin
Authors: Budi Wibowo Nugroho , Faisal Fathani Teuku , Pramumijoyo Subagyo , Indah Marliyani Gayatri
Published: July 2024

The utilization of vs30
data offers numerous applications within the geotechnical field, with one of its primary applications being the determination of site class and the microzonation of site class. vs30
data can be acquired through various methods, including Multichannel Analysis of Surface Waves (MASW), microtremor measurements, and N-SPT data. This study seeks to compare vs30
data and site class criteria based on measurements obtained from MASW, microtremor, and N-SPT data in the Opak River Basin. For the vs30
data analysis, a total of 27 data points from MASW and microtremor measurements, along with 3 data points from N-SPT measurements, were employed. These measurements were conducted across various geological formations, encompassing the young volcanic deposits of Merapi Volcano, alluvial deposits, and the Nglanggran, Sentolo, Wonosari, and Semilir Formations. It is worth noting that all N-SPT data were specifically collected within the young volcanic deposits of the Merapi Volcano Formation. The results of this analysis revealed vs30
values ranging from 159 to 192 m/s for MASW measurements, 156 to 789 m/s for microtremor measurements, and 241 to 249 m/s for N-SPT measurements. In accordance with the SNI 1726-2019 site class criteria, the site classes determined based on vs30
values from MASW and microtremor data included rock (SB), very dense soil (SC), stiff soil (SD) and soft soil (SE), while the site class based on vs30
N-SPT data fell under the stiff soil (SD) criteria. The correlation between vs30
values obtained from MASW and microtremor measurements yielded a strong correlation coefficient (r) of 0.98, and the correlation between vs30
values from MASW and N-SPT measurements demonstrated a very strong correlation coefficient (r) of 0.99.
Numerical Modelling of the Potential Hazard Due to Future Flores Back Arc Thrust Earthquake Generated Tsunami
Authors: Wahyudi  , Sofia S , Armono H D , Mulyadi Y , Sambodho K , Silvianita
Published: July 2024

Indonesia is situated at the conjunction of four major plates: Eurasia, India-Australia, the Pacific, and the Philippine Sea. Therefore, Indonesia is exposed to a considerable threat from natural hazards every day. Tectonic-related marine geohazards, particularly earthquakes-generated tsunamis periodically affect Indonesia, causing great loss of life and extensive damage to property and infrastructure in coastal areas. Many studies on tsunami modeling have been addressed in western Indonesia. In eastern Indonesia tsunamis, however, are even more frequent in occurrence and may be more hazardous, there is a lack of study and less attention. The Flores Back Arc Thrust (FBAT) is an active fault that lies on the sea floor of the Flores Sea in the north of Flores Island, extending from north of Bali to the east that may be connected to the Wetar thrust at the north of Wetar Island in the western Banda Sea. The FBAT is a source of seismicity in this area. From 1900 to 2022, there were 79 earthquakes with a magnitude of more than 6.0 Mw, and 11 of them generated tsunamis, and the most devastating one was the 1992 Flores earthquake tsunami. This study presents an estimated FBAT-induced future earthquake-generated tsunami runup based on numerical modeling.
Evaluation Of The Impact Of Liquefaction Potential On The Construction Of The Solo - Yogyakarta - NYIA Kulon Toll Road
Authors: Wicaksono A , Hardiyatmo H C , Satyarno I
Published: July 2024

The Solo - Yogyakarta - NYIA Kulon Progo Toll Road is one of the projects that aims to improve road network connectivity between Central Java and Yogyakarta. Liquefaction occurred in Yogyakarta after the 2006 earthquake, characterized by sand boiling and lateral spreading. This research was conducted to analyze the potential of liquefaction and evaluate the impacts that occur after liquefaction. The analysis of liquefaction potential uses the method developed by Idriss and Boulanger (2008), the maximum peak ground acceleration value using the earthquake return period of 100 years, 250 years, 1000 years, 2500 years, 5000 years, and 10000 years. Post-liquefaction analyses were conducted by calculating ground settlement developed by Yoshimine et al. (2006) and lateral displacement designed by Zhang (2004). The effect of liquefaction on bored pile foundations was assessed by comparing conditions without liquefaction and with liquefaction. The analysis showed 13 potential liquefaction borehole points with low - high liquefaction susceptibility levels. Post-liquefaction analysis shows that liquefaction can cause 0 cm - 27.32 cm settlement and lateral displacement of 0 cm - 199.24 cm.
Time Histories Finite Element Modelling for Irrigation Canal Stability Analysis under the Effects of Liquefaction in the Sibowi Sigi Regency, Indonesia
Authors: Pucangan A , Rifa’i A , Rahardjo A P
Published: July 2024

The Gumbasa irrigation canals are one of the water resource infrastructures damaged by the 7.5 Mw Palu-Donggala Earthquake in 2018. Canal reconstruction was performed to restore the function of the irrigation network, supllying a potential area of 8000 ha. Main canal construction is known to pass through areas with liquefaction vulnerability, and seismic factors also play a role in the stability of construction. This study discusses the stability of construction under the influence of earthquake loads on the Gumbasa irrigation main canal in the Sibowi area, Tanambulava district, Sigi Regency. The irrigation main canals are built in a landfill on a subbase soil with the potential for liquefaction. Numerical simulations were carried out using the finite element method under two conditions, namely static and dynamic conditions on soil parameters obtained from the Standard Penetration Test (N-SPT) data obtained previously. Based on the analysis results, depths of 6.5 m to 9 m have partial potential for liquefaction, with no significant decrease in safety factor (SF). In the static analysis, the SF is 1.65 and 2.13. In the dynamic analysis, the SF is 1.64 and 2.12. The vertical displacement is minimum 0.03 m and maximum 0.10 m.
Post liquefaction effect on 1 and 2-dimensional model: a case study of Pasigala raw water transmission structure
Authors: Ikhsan M. , Rifai A. , Rahardjo A.P
Published: July 2024

The Liquefaction phenomenon that occurred in Central Sulawesi in September 2018 was triggered by a powerful earthquake that caused extensive destruction and loss of life. Due to its location close to the most active fault in Central Sulawesi, Palu Koro fault, there is still a high probability of recurrence of liquefaction near the area. Ikhsan et al (2023) found that near Sigi regency, certain spots are susceptible to liquefaction occurrence, especially near Maranatha village. This research aims to find the effect after the liquefaction near the Pasigala raw water bridge transmission construction in Sigi Regency if a similar earthquake occurred. It needs to be done because Pasi gala raw water transmission is one of the main raw water supplies to central Sulawesi. Some geotechnical data were carried out in this research such as stratigraphy, SPT, groundwater level, and seismic data. The Post liquefaction analysis was carried out using Idriss and Boulanger (2008) to define one-dimensional settlement potential from the spatial distribution of the liquefaction zone. Numerical models were compared to analyze the settling behavior in a two-dimensional model. The Empirical and Numerical results indicate that the settlement near the abutment’s structure over the 2018 earthquake simulation exceeded the permissible limit of 15 centimeters. This finding may lead to the prediction of damage to the entire structure.
Photogrammetry of airborne image set at high landslide disaster risk region using Meshroom and Blender
Authors: Firdaus A N , Ritonga A R H , Rosandi Y
Published: July 2024

We report the application of the photogrammetry method to reconstruct three-dimensional topographic mesh at a high disaster risk region. This work is aimed to identify the landslide potencies of the area by means of slope analysis of the given area around the Bandung Basin rim. Our method proposes a low-cost aerial survey and an effective algorithm in order to map the local landslide tendencies. In order to perform image processing and 3D representation we utilized the photogrammetric pipeline in the Meshroom software. The post-processing of the 3D model was performed using Blender. In this research, we use a commercial camera drone as an image capturing device. As a test case we processed 183 images of an area of 51 m². The image-processing takes about 39 minutes on a 12 cores computer accompanied with a GPU card. From this set of images, we have yielded a three-dimensional slope structure comprising a total of 85,850 mesh nodes. As the result of this research, we propose the optimization of the image set and a list of post processing works of the nodes that can be used in order to characterize landslide disaster risk of the disaster-prone region in a fast and accurate manner.
Rock Mass Quality Type Analysis On The New Kretek Girijati Road Construction Site Based On Reconnaissance Survey
Authors: Sasangka Daru Jaka , Ismanda Yayi , Saputra Bayu Sukarjono Bagus
Published: July 2024

The research activity was carried out at the location of the national road construction plan for The Kretek-Girijati Road Section. The National Kretek-Girijati Section is in the Nglanggran Formation, which consists of volcanic breccias, agglomerates, tuffs, andesitic-basalt and andesitic lava flows, and the Wonosari Formation, which is dominated by carbonate rocks consisting of layered limestone and massive limestone. This investigation aims to obtain a typical analogy of excavation slopes at road construction sites, making recommendations for additional drilling locations and geophysical surveys for appropriate data by making an engineering geological map. Based on the geological engineering description, the location plan for the construction of The Kretek-Girijati Road Section is dominated by limestone and andesite. The types of limestone rock mass quality consist of Massive limestone (very hard) with good to very good rock mass quality with a GSI value of >80 and Clastic limestone with poor to medium rock quality with a GSI value of 30 – 60. The types of andesite rock mass quality consist of massive andesite (weakly jointed) with good – excellent rock mass quality with an RMR value of 70-80 and moderately fractured andesite with moderate rock mass quality (good 50 – 70).
Investigation of the Extent of Hydrothermal Activities of the Sikidang Crater, Dieng Volcanic Complex (Central Java), Using Geomagnetic Method
Authors: Miftahcahyani N.I. F. , Utami P.
Published: July 2024

The Sikidang Crater (± 2000 m asl) is one of the active craters in the Dieng Volcanic Complex (DVC). It is situated on the southeastern flank of Mt. Pangonan. The crater is significant for development of both tourism and energy sectors in Dieng. Thermal manifestations inside the crater which consist of boiling mud pools and pots, hot springs, fumaroles, gas vents, steaming and altered ground make the place a popular tourist attraction. They also serve as windows to the shallow subsurface processes and help better understand the dynamics of the Dieng geothermal system. However, the land use of the crater and its vicinity disregards the fact that the actual extent of the hydrothermal activity of the crater has not been figured out, and that the foci of the thermal fluid discharges in the crater often shift. Some agriculture plots, housing areas, as well as tourism and geothermal infrastructures are located within or near the morphological boundary of the crater. The inherent hydrothermal hazard of the crater therefore, must be well mitigated to minimize the negative impacts to the people, as well as their assets. Our research aims to delineate the lateral and vertical extent of the hydrothermal activity of the crater by geomagnetic method. Geomagnetic anomaly in geothermal field occurs due to the difference in the intensity of hydrothermal alteration of the rocks. The equipment used was a pair of Proton Precision Magnetometers GEOTRON G5. Our result shows that low geomagnetic anomaly (-2200 to -400 nT) correlated with demagnetized, hydrothermally altered andesitic rocks covers an area of ≥ 1.15 km2, i.e., more than seven times larger than the area outlined by morphological boundary of the crater. The anomalous zone extends N/NE - S/SW from beyond the areas of inter-volcanic plain between Pangonan and Igir Binem in the north, to the areas beyond Sikunang and Kendil cones in the south. Below the Sikidang mud pool the demagnetized rock mass reaches a maximum thickness of 2000 m. The supporting data, i.e., the fluctuations of the gas discharge, and the seismicity of the DVC indicate that the recent dynamics of the Sikidang Crater is mostly controlled by the internal processes within the crater.
The Analysis of Permeability Influence on CO2 Plume based on Reservoir Simulation
Authors: Lo Julian , Komara Eki , Utama Widya
Published: July 2024

Permeability is critical in site characterization and geoscience studies for carbon capture and storage projects. There is significant uncertainty of CO2 movement in the subsurface caused by permeability. This study aims to analyze the influence of permeability on the movement of CO2 plumes using a synthetic single-porosity model based on reservoir simulation. By simplifying geomechanics, employing tornado experimental design, as well as utilizing Pearson and Spearman correlations from 30,000 neural network proxy models based on Latin Hypercube and Monte Carlo experimental design, this research successfully explains the impact of permeability on CO2 movement. The reservoir can withstand pressures up to 6500 psi without rock failure. The total CO2 injection with a 90% probability is ∼1.3 TSCF equivalent, with an injection rate of 30 MMSCFD, optimized for a duration of 120 years. Initially, the CO2 movement tends to be upward during injection due to gravitational effects, but over time, it tends to move laterally. Vertical permeability exhibits a negative correlation with total CO2 injection, lateral distribution of CO2 plumes, and CO2 solubility in water. On the other hand, horizontal permeability shows a positive correlation with total CO2 injection. Factors such as perforation location and layer thickness also influence the extent of permeability’s role. However, the lateral and vertical movement of CO2 in this study has not been fully identified, and more complex quantification formulas are needed in commercial simulators. Despite the limitations in data and computational resources, this research successfully explains the movement of CO2 plumes and highlights the importance of other factors such as porosity, perforation location, layer thickness, among others. The recommendations of this study include the use of more complex quantification formulas to model the movement of CO2 plumes, along with increasing the complexity of the model.
Petrological and mineralogical characteristics of “red material layer” in Patuha geothermal field, Bandung, West Java
Authors: Pradana E P A , Setiawan N I , Sesesega R S
Published: July 2024

Patuha Geothermal Field is located in Ciwidey, Bandung, West Java Province, with a total resource potential of approximately 400 Mwe (Megawatt electric). With such potential, seven power plants have been developed in Unit-1, capable of producing 60 MWe of electricity, and are currently being developed in stages for Unit-2. In the development of the Unit-2 power plant, there was a problem where collapse occurred around the drill hole area, especially since the color of the material that came out during drilling was red. We call this material the red material layer (a layer composed of red material). This problem also occurs in Unit-1. This research aims to characterize the type of red material layer to see why this problem occurs in this layer. We studied the petrological and mineralogical characteristics of the red material layer by cutting rock samples from six drill holes in Unit-1. The analytical methods used were megascopic observation, petrography, and XRD (X-ray diffraction) to determine the mineral content texture and identify the material’s origin, including clay minerals, alteration, and oxidation mineral aggregates. The petrological and mineralogical analysis found that the red-colored material is dominated by hematite, with some samples containing magnetite. We found four characteristic types of red layer material and four types of textures that appeared in iron oxide minerals: rim, vein, matrix replacements, and fragment replacements. We conclude from the visible vein texture that oxidation occurs due to oxygen penetration through gaps of a fault/fracture/joint. This oxidizes the area around the vein and then undergoes hydrothermal change. Meanwhile, those that do not have a vein texture are considered material resulting from an oxidation process on the surface, which is then deposited and undergoes hydrothermal change to contain oxide minerals such as hematite and magnetite. Apart from that, XRD observations also found high amounts of clay minerals such as chlorite, smectite, kaolinite, illite-smectite mixed layers, and chlorite-smectite mixed layers. The presence of these clay minerals is thought to cause a collapse in the area around the drill hole because its swelling and exfoliation properties are reactive to fluids, especially drilling fluids.
Petrology and geochemistry of Mount Lurus lavas: evidence for alkaline to subalkaline transition in the rear arc of Java, Sunda Arc
Authors: Mumtaza T H , Handini E , Hasenaka T , Mori Y , Khasanah T N
Published: July 2024

Mount Lurus, a small Quaternary volcanic center in the rear of Java Island, Sunda arc, has erupted both alkaline and subalkaline lavas in a short span of active period. Furthermore, this small volcanic edifice, together with its neighboring alkaline volcanic center of Ringgit-Beser, corresponds to a shallower slab depth (∼160 km) than Muria in Central Java (270 km). We report the mineralogical and geochemical characteristics of Lurus lavas and compare them to the Ringgit-Beser lavas. All Lurus lavas show typical characteristics of island arcs with elevated Ba, Sr, Pb, and K and negative anomalies of Nb and Ti. The older Lurus edifice (Old Lurus) produces alkaline lavas with high alkalinity, which are trachyandesite and phonotephrite in composition. The younger Lurus (Young Lurus) generates calc-alkaline lavas with basaltic andesite composition. Both groups have plagioclase, clinopyroxene, olivine, and opaque minerals as phenocrysts phase. Leucite is found in one sample of Old Lurus with the lowest SiO2 content (48.92 wt%) and highest alkali content (5.38 wt%). Old Lurus lavas tend to show higher contents of incompatible elements (Pb, Ba, Nd, and Rb) than Young Lurus. The mineralogical and compositional differences between these lavas suggest that these magmas are sourced from at least three magma chambers of distinct composition: highly potassic magma chamber (comparable to the evolved-K series of Ringgit-Beser) and hydrous-potassic magma which fed Old Lurus edifice; and calc-alkaline magma chamber which fed Young Lurus edifice.
Geology and Ore Mineralization Characteristics of the Selodong Prospect, Lombok Island, Indonesia
Authors: Kirom N , Idrus A , Setijadji L D , Vanessa A
Published: July 2024

The Selodong prospect is located in the southwest sector of Lombok Island which tectonically lies within the W-E trending Sunda-Banda magmatic arc, which hosts various gold-base metal mineralizations including porphyry and epithermal deposits. Lombok Island, particularly southwestern portion of the island is known to hosts gold, silver and copper prospects, including Selodong prospect. The Selodong prospect is divided into several sub-prospect areas which include the Blongas, Montong Botek, Kekalik and Belikat. However, this study only focuses on the Blongas sub-prospect. The study is aimed to discusses the geology, characteristics of alteration and mineralization of the sub-prospect. To achieve the objective, some methods such as mapping and numerous laboratory works were conducted. Petrography to identify alteration minerals, ore microscopy to identify type of ore minerals, and fluid inclusion microthermometry to characterize ore fluid were performed. The geological conditions of the study area are composed of andesite lava, andesite breccia, diorite intrusion and alluvial deposit. Typical porphyry alteration type i.e., potassic is present. Argillic, silicic, advanced argillic, propylitic and phyllic alterations are also identified. The distribution of potassic and some argillic alteration is controlled by lithology, while silicic alteration, advanced argillic, propylitic and some argillic alterations are controlled by geological structures with an NW-SE and NE-SW trending patterns. Propylitic alteration is characterized by chlorite + epidote + calcite ± clay. Argillic alteration is marked by the presence of clay minerals such as clay + quartz. Advanced argillic alteration is typified by quartz + alunite + pyrolusite ± paragonite. Phyllic alteration is typified by sericite + quartz ± clay. Potassic alteration is marked by secondary biotite + quartz ± clay. Silicic alteration is marked by quartz + pyrolusite + epidote. Ore mineralization in the study area is associated with massive and stockwork vein textures. Ore and metalliferous minerals are found as magnetite, chalcopyrite, pyrite, hematite, goethite, jarosite, sphalerite, pyrrhotite, chalcocite and native gold. Generally, homogenization temperatures in the research area range from 543 - >600 °C, with salinity of 26.3 - 73.95 wt.% NaCl eq associated with potassic alteration, whereas homogenization temperatures range from 251 to 349 °C, with salinity of 5.46 - 8.38 wt.% NaCl eq. associated with silicic alteration. Based on those characteristics, the prospect in the study area indicates a porphyry deposit type, which is transition to high sulfidation epithermal.
Mineralogical and ore-fluid characteristics of the Onto Porphyry-HSE transition in Hu’u district, West Nusa Tenggara, Indonesia
Authors: Putra Z A M , Idrus A , Warmada I W
Published: July 2024

Onto prospect is located in the eastern part of Sumbawa Island in West Nusa Tenggara Province, Indonesia. The island is situated within the Sunda-Banda magmatic arc, which extends from west to east, consists of volcanic rocks from the early Miocene to the Holocene. Onto is one of the highly potential prospects and holds significant economic value among ore deposits in Indonesia. The aim of this research is to explain the geological setting and determine the genesis of mineralization based on petrographic, ore microscopic, and fluid inclusion analyses. Eight lithological units have been identified, namely early andesites, polymictic diatreme breccia, upper sedimentary package, caping andesite, quartz-phyric andesite sill, early porphyry, early intra-mineral porphyry, and late intra-mineral porphyry. Nine samples were analyzed for petrography to identify the alteration types consisting of illite-smectite, quartz-dickite, residual vuggy quartz, silicic, quartz-alunite, quartz-pyrophyllite±diaspore, potassic, phyllic-chloritic, and propylitic alterations. Additionally, pyrite, chalcopyrite, and covellite are predominantly present in the study area. Meanwhile, native gold is found as an inclusion in covellite and pyrite. From micro thermometric analysis of fluid inclusions in quartz veins associated with multiphase intrusive rocks, it is shown that the homogenization temperature of early porphyry ranges on average from 279°C to 377°C, early inter-mineral porphyry ranges from 263°C to 361°C, and late intra-mineral porphyry ranges from 275°C to 336°C. The salinity level of the measurements ranges from 5.71 to 10.27% by weight NaCl equivalent, with an average of approximately 8.15% by weight NaCl equivalent. The mineralization formation during the early or prograde phase is associated with the EDM vein system with a mineralization set of biotite-magnetite, digenite, chalcocite, and coevellite, type A veins with quartz-sulfides + anhydrite, M veins type associated with quartz-magnetite-chalcopyrite-bornite mineralization, AB veins type associated with quartz-sulfides + anhydrite textures, and B veins type with sulfide centerline characteristics. The mineralization system during the early stage is generally associated with potassic alteration (K-feldspar-magnetite-secondary biotite). Whereas the retrograde phase, the vein system is associated C veins type with sulfide mineralization groups consisting of massive chalcopyrite + quartz with phyllic alteration (quartz-muscovite-chlorite ± dickite), D veins type with quartz-pyrite+chalcopyrite associated with advanced argillic alteration (quartz-alunite-pyrophyllite ± diasporite), E veins representing the epithermal stage associated with minerals such as quartz-carbonates, galena, sphalerite, chalcopyrite, tetrahedrite-tennatite in the alteration stage of kaolinite-illite-smektite-sericite.
The Influence of Concrete Age on the Accuracy of Pile Integrity Testing on Bored Piles Foundation
Authors: Santoso H.T. , Hartono J. , Andani R. , Primaswari G.
Published: July 2024

Bored pile foundations are defined as deep foundations in the form of an elongated tube with a specific diameter made of reinforced concrete installed using the drilling method and in-situ casting concrete. The cast in-situ process in bored holes with a deep elevation below the ground surface can potentially cause integrity problems, such as voids, segregation, fracture, necking, bulging, and other concrete defects. Currently, many non-destructive test methods are available to ensure the quality of the bored pile; one is the Low Strain Integrity Testing method, also known as Pile Integrity Testing (PIT). ASTM recommends that PIT should be carried out no sooner than 7 days after casting or the strength of the concrete has reached a minimum of 75,0% of its design strength. In fact, the PIT test is carried out before the concrete’s age and/or its strength is achieved, considering the limited construction time. This could lead to misinterpretation of the PIT test results and inaccurate identification of the bored pile defect locations. The study aims to determine the effect of concrete age on the accuracy of bored pile defect locations on a laboratory scale. The test model consisted of four bored piles with a diameter of 0,3 meters and a depth of 2,0 meters, which were cast using reinforced concrete with a design strength of fc’ 30 MPa. The PIT was performed at <7, 14, and 28 days of concrete age, and then the confusion matrix method was used to create a binary classification model to determine the accuracy of the defect location. The defect locations were visually observed and validated by dismantling the test model after 28 days of casting. The results showed that the accuracy of identifying the location of concrete defects was not affected by the age of the concrete but was determined by the compressive strength of the concrete during testing. Referring to the F-score, bored piles with concrete strength >75,0% of the design accurately identify defect locations above 84,21%. On the other hand, bored piles with concrete strength <75,0% design resulted in accuracy below 66,67%.
Sequence Stratigraphy and Depositional Environment of the ‘Perahu’ Sand, Bekasap Formation, ‘DAP’ Field, Central Sumatera Basin
Authors: Putra M D A , Husein S , Multihadi
Published: July 2024

The ‘DAP’ Field is one of the oil and gas fields within the Central Sumatera Basin that is proven to have hydrocarbon reserves. One of the proven reservoirs in the ‘DAP’ Field is the ‘Perahu’ Sand, Bekasap Formation. This study aims to determine the depositional environment and facies distribution focusing on the ‘Perahu’ Sand, Bekasap Formation through a sequence stratigraphic approach. The research was based on an integrated analysis of sedimentary facies from one core data and a key well log to interpret the facies association. Then the key well is correlated to eight other well logs with the help of sequence stratigraphic concept to determine the depositional facies distribution and succession at the study interval. Lithofacies that are identified from core data were interpreted as floodplain, tidal channel, mud flat, mix flat, and sand flat, hence the depositional environment of ‘Perahu’ Sand was interpreted to be a tide-dominated estuarine. The parasequence set level of Bekasap Formation was interpreted to be in a transgressive system tract, with the ‘Perahu’ Sand divided into three flooding surfaces that is FS3, FS4, and FS5. The FS3 distribution consists of tidal-fluvial channel, crevasse splay and floodplain facies. The FS4 distribution consists of two tidal channels and one sand flat facies. The FS5 distribution consists of one sand flat facies. The depositional trend of the ‘Perahu’ Sand shows a northeast to southwest trend, with basinward toward southwest.
Sandstone facies distribution of potential reservoirs within lower talang akar formation in ‘Jasmine’ Field, Northwest Java Basin
Authors: Jasmine S R , Setyowiyoto J , Winardi S , Amrizal
Published: July 2024

‘Jasmine’ Field is an oil and gas field in the working area of a national oil company located in Northwest Java Basin. Lower Talang Akar Formation is considered to have one of the largest sandstone reservoir potentials in Northwest Java Basin based on earlier studies. This study aims to determine the depositional environment of Lower Talang Akar Formation and get the sandstone facies distribution of potential reservoirs in ‘Jasmine’ Field, as an early guideline for future production and drilling in new points within the field. Interpretation of this study was carried out by integrating 13 well log data, 13 well report data, 2 core data, and 1 3D seismic cube. Well log, well report, and core data were integrated to interpretate lithofacies, electrofacies, depositional environment, and stratigraphy sequence analysis. Sandstone body width vs. thickness ratio determination, fluid contact analysis, and RMS seismic attribute method were then carried to obtain the sandstone facies distribution of potential reservoir intervals of Talang Akar Formation in ‘Jasmine’ Field. The results shows that there are 2 intervals that has thick sandstone bodies as potential reservoirs in this study. The deposition direction for both Sandstone Body-A group and Sandstone Body-B group intervals is northeast-southwest. Sandstone Body-A group facies distribution is controlled by a braided river depositional environment and is distributed in the west side of the field. In the other hand, Sandstone Body-B group facies distribution is controlled by a distributary channel system in a lower delta-plain depositional environment and is distributed in both the west side and east side of the field.
Advancing the automated foraminifera fossil identification through scanning electron microscopy image classification: A convolutional neural network approach
Authors: Harbowo D G , Muliawati T
Published: July 2024

Handling more than thousand fossil foraminifera data is very challenging, especially for old-way identification. Determining morpho-taxonomy by conventional microscopic observation is very time-consuming and can lead to innacuracy identification. We are certain that the process could be advanced through big data analysis using a machine learning approach. Foraminifera fossils have already become a common standard for biostratigraphic proxies and paleoenvironmental interpretation. Therefore, the objective of this study was to develop an automated identification method using Convolutional Neural Networks (CNN). We used standardized Scanning Electron Microscopy (SEM) images of foraminifera acquired from various open-source databases for image classification. The analysis was conducted using Python programming language in Google Colaboratory. The image dataset is categorized based on its genus (n: 138) and divided into training and test/validation data for accuracy simulation (total image: 1833; data training: 1387; test/validation: 237/237). The best-fit accuracy values of the training-data and testing-data were between 97-86%:73-77%, with parameters including epoch number ranging up to 40, learning rates of 0.05, and a batch size of 64. These values indicate good prospects for foraminifera SEM Image taxonomic classification, demonstrating a noteworthy level of identification accuracy (63%). The outcomes of this study offer a new method for further effective automated morpho-taxonomic identification of foraminifera fossils using other conventional optic microscopy.
Evaluation of release wells for liquefaction mitigation using numerical simulation
Authors: Purbawati O , Faris F , Istiarto
Published: July 2024

The liquefaction phenomenon in sandy soil due to an increased pore-water pressure ratio during an earthquake can have significant consequences. The 2018 liquefaction event in Sibalaya, Central Sulawesi, highlights the need for mitigation measures to prevent similar incidents. This study evaluates the efficacy of constructing release wells along the Sibalaya segment of the Gumbasa irrigation canal to mitigate liquefaction using Standard Penetration Test data. The aim is to protect irrigation canal facilities and roads from recurrent flow liquefaction in Sibalaya. The release well is designed to rapidly dissipate the abnormally elevated pore water pressure that may occur during an earthquake. This study uses numerical simulations with the integration of Geostudio 2022.1 software, namelyQUAKE /WandSEEP /W. Simulation results comparing the Sibalaya location with and without the release well indicate that the latter is effective in preventing recurrent liquefaction in the Sibalaya region. Therefore, the construction of release wells is recommended as a viable mitigation measure against liquefaction.
Shallow groundwater quality around the area Kaligending final processing site in Kebumen Regency, Central Java Province
Authors: Widiyanto K , Raharjo P D , Hastria D , Puswanto E , Farisan A , Wibowo D A
Published: July 2024

The location of the Kaligending final Processing site is in Kraminan, Kaligending Village, Karangsambung District, Kebumen Regency which is the place for final waste processing. The Kaligending final processing site which is located in the hills can have an environmental impact on the area located below it. One of the impacts is the condition of groundwater in the area. The purpose of this study is to determine the condition and quality of shallow groundwater in the area. To find out groundwater conditions especially position and the pattern of shallow groundwater flow in the area is measured in the shallow ground water level which is then made a map of shallow groundwater and shallow groundwater flow direction patterns, while groundwater quality is measured by electrical conductivity and total dissolve solid (TDS) shallow groundwater in several wells. The results of the map pattern of shallow groundwater flow directions in the area come from the east and northeast, groundwater quality based on electrical conductivity is still suitable for use. The quality of shallow groundwater in residents’ wells in the Kraminan area is based on total dissolved solids, there are 4 wells that exceed the upper limit of drinking water quality standards (wells 3, 4, 5 and 6) which are located close to the Krembeng River
Machine Learning for Mapping the Distribution of Clay Minerals in Sidoarjo Mud Volcano (LUSI) Using Support Vector Machine (SVM) Algorithm
Authors: Dhiyaulhaq I D , Warmada I W , Setianto A
Published: July 2024

Sidoarjo Mud Volcano (LUSI) is a natural phenomenon that has led to the emergence of volcanic mud eruptions in the city of Sidoarjo, East Java Province, with a generated volume of volcanic mud of approximately 80.000 m3 per day. However, only about 60.000 m3 can be managed daily, resulting in an excess of volcanic mud that accumulates and overflows into the surrounding area from the center of the mud eruption. This volcanic mud include high-temperature gas and fluid, which pose significant obstacles and limitations for conducting research at the location. Remote sensing methods, which involve measuring the electromagnetic spectrum energy emitted by an object without direct physical contact in the field, have been employed as a solution to overcome the limitations of access. The Advanced Spaceborne Thermal Emission and Reflection (ASTER) satellite’s image data will be utilized, specifically the Short-Wave Infrared (SWIR) subsystem consisting of bands 4 to 9. This subsystem is selected due to its high reflectance sensitivity to clay minerals, allowing for easy recognition and identification of the imagery. SWIR data will be extracted using band ratio math, which involves sensitive band combinations for specific minerals, followed by normalization to minimize atmospheric effects and provide optimal and clay-sensitive outcomes. The resulting SWIR extraction data, amounting to 58.164 data points, will be subjected to the machine learning method of the Support Vector Machine (SVM) algorithm to maximize classification accuracy. The dataset will be divided into 40% training data and 60% testing data. The training data will establish the foundational model for the SVM algorithm, which will subsequently be utilized by the Support Vector Classifier (SVC). The SVC will employ the Radial Basis Function (RBF) kernel with a gamma parameter value of 10 and a C parameter value of 750. Based on these decisions, the entire dataset can be classified using the established parameters, resulting outcome in the form of a distribution map of clay minerals in Mount Lumpur Sidoarjo (LUSI). The presence of clay minerals, including Kaolinite, Chlorite, Illite, and Smectite, will be uniformly and predominantly distributed in the northern direction from the center of the volcanic mud eruption site.
Characteristics of Earthquake Mechanisms Along the Andaman - Nicobar Region derived from Bayesian Moment Tensor Inversion
Authors: Gunarya M.H. , Simanjuntak Andrean V. H. , Muksin Umar
Published: July 2024

Earthquake activities in the Andaman - Nicobar region are generated mainly by several active faults and an active subduction zone that can activate multiple hypocenter clusters. Therefore, studying the seismotectonic process from source mechanism analysis using moment tensor inversion is essential. In this research, we applied a stochastic Bayesian inversion using Grond, a framework tool for moment tensor (MT) inversion, to characterize the earthquake mechanisms and the most appropriate centroid locations. Procedurally, several of the largest earthquakes with a moment magnitude Mw > 5.5 from 2007 to 2023 were analyzed using the regional and teleseismic networks up to 2000 km from the epicenter based on 1 Hz green function model and azimuthal gap coverage. We applied 10,000-30,000 iterations of inversions with 300 bootstrap chains for a stable result. The low-frequency bandpass with a range of 0.007 - 0.03 Hz was chosen for the inversion process. There were 17 solutions for earthquake mechanisms with good misfit values of < 0.65. Based on the division of the 5 clusters with the highest seismicity, the selected earthquakes’ source mechanism is dominated by strike-slip and oblique faulting. The results were compared with existing data catalogs showing differences in hypocentre and fault orientation direction, particularly for strike-slip earthquakes in the shallow crust and mantle zones.
Vesicularity, Density, and Crystal Size Distribution of Pumice-Scoria at South-Southeast Flank of Merapi Volcano: A Window Into Explosive Volcanic Eruption
Authors: Jovian A H , Handini E , Wibowo H E , Warmada I W , Syarifah V
Published: July 2024

Merapi, one of the most active volcanoes in Java Island of Sunda Arc, is a constant threat to the ten million people who live within its 10-km radius of the summit. In 2010, it experienced an explosive eruptive event, sending pumice-laden pyroclastic density currents (PDC) that extended as far as 15 km down its southeastern flank. We report field observations of PDC deposits on the south-southeast flank of the volcano and calculate the vesicularity, density and crystal size distribution of pumice–scoria fragments. The density of the pumice–scoria is measured by archimedes’ principle by weighting the sample in water. The vesicularity is determined from petrography using the point counting method. Crystal Size distribution (CSD) is determined by images from thin sections using plagioclase crystals to calculate the magma residence time. Based on their physical appearance, the pumice–scoria fragments from this area are grouped into: (1) white pumice, (2) grey pumice, and (3) dark scoria. The density of white pumice is overlapping with the grey pumice group (1.5-2 g/ml); while the dark scoria is the densest among others (>2 g/ml). The vesicularity of pumice–scoria ranges from 7-30%. CSD analysis is done in two most vesicular samples from each group. The CSD result gives both shallow and steep slopes which reflect the crystal size and population density. The slope suggests that magma residence times are (a) 11.49–249.68 years for grey pumice, (b) 5.03–194.54 years for white pumice, and (c) 3.83–273.36 years for dark scoria. This research suggests that the three types of pumice–scoria from the study area generally have similar crystallization path and time. Our CSD data shows that these pumice-scoria samples tend to have steeper slopes than lava samples, indicating a more uneven crystal-growth condition.
Bioinks for bioprinting using plant-derived biomaterials
Authors: Hasan Md Mehedee , Ahmad Ashfaq , Akter Mst Zobaida , Choi Yeong-Jin , Yi Hee-Gyeong
Published: July 2024

Three-dimensional (3D) bioprinting has revolutionized tissue engineering by enabling the fabrication of complex and functional human tissues and organs. An essential component of successful 3D bioprinting is the selection of an appropriate bioink capable of supporting cell proliferation and viability. Plant-derived biomaterials, because of their abundance, biocompatibility, and tunable properties, hold promise as bioink sources, thus offering advantages over animal-derived biomaterials, which carry immunogenic concerns. This comprehensive review explores and analyzes the potential of plant-derived biomaterials as bioinks for 3D bioprinting of human tissues. Modification and optimization of these materials to enhance printability and biological functionality are discussed. Furthermore, cancer research and drug testing applications of the use of plant-based biomaterials in bioprinting various human tissues such as bone, cartilage, skin, and vascular tissues are described. Challenges and limitations, including mechanical integrity, cell viability, resolution, and regulatory concerns, along with potential strategies to overcome them, are discussed. Additionally, this review provides insights into the potential use of plant-based decellularized ECM (dECM) as bioinks, future prospects, and emerging trends in the use of plant-derived biomaterials for 3D bioprinting applications. The potential of plant-derived biomaterials as bioinks for 3D bioprinting of human tissues is highlighted herein. However, further research is necessary to optimize their processing, standardize their properties, and evaluate their long-term in vivo performance. Continued advancements in plant-derived biomaterials have the potential to revolutionize tissue engineering and facilitate the development of functional and regenerative therapies for diverse clinical applications.
The importance of interlaboratory studies for robust measurements of graphene and other 2D materials
Authors: Paton Keith R , Pollard Andrew J
Published: July 2024

This perspective article presents the current state of interlaboratory studies in graphene and other 2D materials. These interlaboratory studies are mostly coordinated via the Versailles Project on Advanced Materials and Standards and are crucial in establishing robust and validated protocols for measuring key properties of these materials. These protocols can then be included in international documentary standards. We summarise the key findings of completed studies and outline the approach of those that are currently underway. An outline of future needs is also presented, highlighting gaps in the current scope of activities and therefore where the focus of future studies should be.
In-situ synthesis of quaternary alkylammonium ligand capped organic-inorganic hybrid halide perovskite for high pure green luminescence in display application
Authors: Rao Maithili K , Paramasivam Selvaraj , Selvakumar M , Santosh M S , Mahesha M G , Senthilkumar S
Published: July 2024

This study delves into the intricate dynamics of ligand engineering for the synthesis of Methyl Ammonium Lead Bromide (MAPbBr3) nanocrystals (NCs), which exhibit immense potential in optoelectronic and photovoltaic applications. Our focus centres on the role of the quaternary ammonium molecule CTAB as a ligand in stabilizing MAPbBr3 NCs. This also addresses the challenges related to the stability and surface defects of NCs that hinder their commercial viability. Employing a modified ligand-assisted reprecipitation technique (LARP) with a dual solvent system, we optimized the CTAB concentration to 0.05 mmol, resulting in MAPbBr3 NCs with an impressive 88% quantum yield. XPS and FTIR analyses confirm the presence and binding of CTAB on the NC surface. The MAPbBr3-CTAB NCs exhibit higher exciton–phonon binding energy, enhancing their optical properties. Despite an unfavourable geometric fit, CTAB is effective in surface defect passivation due to its binding, solvation, and desorption energy during the dynamic binding process. 2D-DOSY NMR reveals approximately 66% CTAB bound to the NC surface. A comparative study involving MAPbBr3-OA, OLA, and MAPbBr3-CTAB deposited on LEDs demonstrates the superior performance of the latter, achieving a luminous efficiency of 42.18 lm W−1 at 1.2 ml deposition. These findings highlight the efficacy of CTAB in achieving high-purity green luminescence, aligning with BT.2020 display colour standards and paving the way for advanced optoelectronic applications. The successful synthesis and improved performance of MAPbBr3-CTAB NCs underscore their potential as a promising material for future optoelectronic and photovoltaic technologies.