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At the research location at PT. Ansaf Inti Resource, there are several mining stages such as exploration. In the exploration itself, drilling and logging activities are carried out. However, if not careful in calculating coal resource estimates, there can be potential discrepancies between the estimated coal resources based on the results of drilling data identification and well logging data with the actual results. Exploration activities are activities that are often carried out by companies to determine reserves in an area. Without carrying out these activities, companies will have difficulty estimating the profits to be obtained. To obtain the data needed to carry out exploration activities such as calculating the quality and quantity of coal, it is necessary to carry out drilling such as the full coring method and also carry out logging activities to complete the data and also as comparative data from core drilling. Coal Resources are part of a coal deposit in the form of a certain quantity and have reasonable prospects that allow for economic consideration. Coal resources are divided according to the level of geological confidence into inferred, indicated, and measured categories. Therefore, in this study, the author will calculate coal resources from exploration data collection such as coring data, cutting data, and well logging data as well as coal quality data and process it in Minescape 5.7 software so that it can obtain an estimate of coal resources for each seam at the research location.

Travertine is a non-marine carbonate rock precipitated from calcium- and bicarbonate-rich waters, commonly associated with hot springs, streams, and lakes in tectonically active regions. This study presents a systematic literature review of travertine deposit characteristics, encompassing mineralogical composition, geochemical signatures, petrographic textures, morphological types, isotopic properties, biotic–abiotic controls on formation, early diagenesis, and petrophysical implications. The synthesis indicates that travertine is predominantly composed of calcite, with aragonite forming under conditions of elevated temperature, high Mg/Ca ratios, and rapid CO₂ degassing. Travertines display exceptional textural diversity, ranging from abiotic crystalline crusts to microbially mediated fabrics such as shrub, peloidal, and stromatolitic structures. Major morphologies include fissure ridges, mounds, terraces, cascades, and slopes, strongly governed by tectonic setting, topography, hydrology, and substrate geology. Stable isotopes (δ¹³C and δ¹⁸O), strontium isotopes, trace elements, and REE patterns effectively constrain fluid provenance and distinguish thermogene from meteogene travertines. Microbial activity plays a crucial role in biomineralization, influencing precipitation rates, crystal morphology, and lamination patterns. Early diagenetic processes occurring during active deposition may significantly modify primary fabrics and geochemical signals. Travertine petrophysical properties exhibit distinctive porosity–velocity relationships, making them valuable analogues for subsurface carbonate reservoirs. This review highlights that travertines record complex interactions among physical, chemical, biological, and geological processes and hold significant value for paleoenvironmental reconstruction and carbonate reservoir studies.

Blasting is a critical method for overburden removal in open-pit coal mines, where fragmentation quality directly impacts loading efficiency and operational costs. This study aims to analyze the actual fragmentation resulting from overburden blasting at Pit 4 Middle of PT. Victor Dua Tiga Mega, Central Kalimantan, to predict fragmentation using the Kuz-Ram model, and to evaluate the conformity of both results against the company standard (boulder size ≤144.6 cm or ≥50 cm for analysis). The research employed a quantitative comparative method. Primary data included blasting geometry and photographs of muck piles from 10 blasting events, which were analyzed using WipFrag software to obtain actual fragmentation distribution. Secondary data comprised rock characteristics and explosive properties for Kuz-Ram prediction input. The results showed significant variation in actual boulder percentage (≥50 cm), ranging from 6.19% to 32.91% with an average of 16.05% (medium category). Statistical analysis revealed a very weak negative correlation (r = -0.21) between powder factor (PF) and boulder percentage, indicating that PF is not the dominant factor within the consistent application range (0.21-0.23 kg/bcm). Comparison with Kuz-Ram predictions showed that the model consistently over-predicted coarse material, with an average difference of +25.21%, suggesting the need for rock factor (A) recalibration. It is concluded that the blasting results are inconsistent, strongly influenced by uncontrollable factors such as geological conditions. Recommendations include geometri evaluation, particularly burden and spacing, and calibration of the Kuz-Ram model for more accurate future predictions.

Facies analysis and thin-section petrography are complementary and essential approaches for determining the lithological characteristics of deep-water deposits. Deep-water sediments are formed by diverse depositional processes such as turbidity currents, debris flows, slumps, and pelagic suspension settling, producing a wide range of lithofacies with distinctive textural, compositional, and sedimentary structural attributes. This literature review synthesizes studies that apply facies analysis and thin-section petrography to characterize deep-water deposits across various basins and geological ages worldwide. Field-based facies analysis emphasizes lithology, sedimentary structures, bed geometry, and vertical–lateral facies relationships to reconstruct depositional environments. In contrast, thin-section petrography provides microscopic insights into mineral composition, grain texture, cement types, porosity, and diagenetic features that are not observable in the field. The integration of these methods, often combined with advanced techniques such as XRD, SEM, and geochemical analyses, has proven effective in distinguishing lithofacies, understanding sedimentary processes, and evaluating reservoir quality. The review highlights that grain size, sorting, cement type, pore-throat size, and diagenetic processes are key controls on lithological characteristics and reservoir potential in deep-water systems. Therefore, the combined application of facies analysis and thin-section petrography provides a comprehensive framework for interpreting deep-water sedimentary systems.

This study aims to reflect on the theological meaning of natural disasters in Sumatra (Aceh, Simeulue, Padang) from an ecological perspective. Although Sumatra is geologically prone to earthquakes and tectonic activities due to its location on the Pacific Ring of Fire, hydrometeorological disasters such as floods and landslides are exacerbated by human actions, including deforestation, watershed degradation, and uncontrolled land conversion. This research employs a qualitative-descriptive approach using library research and a theological-reflective method. Primary sources include Sacred Scripture, Church documents (Laudato Si', Gaudium et Spes, General Directory for Catechesis), and relevant ecological theology literature. The findings indicate that natural disasters in Sumatra can be interpreted as "signs of the times" revealing both ecological and moral crises. Disasters are not divine punishment but consequences of humanity's misuse of freedom in managing creation. Ecological conversion is urgently needed at personal, social, and structural levels. Within the catechetical framework, disaster experiences become "texts of life" that guide the faithful toward mature faith expressed in lifestyle changes, solidarity, and responsibility for our common home.

Landslides in the Giritengah Catchment Area are influenced by several factors, including geological conditions, rainfall intensity, geomorphology, soil characteristics, and inappropriate land use practices, all of which affect regional spatial planning and environmental stability. This study presents a literature review that analyzes landslide vulnerability, evaluates the impact of land use changes, and proposes integrated Soil and Water Conservation Techniques (SWCT) to support sustainable land management. The analysis applies Geographic Information System methods using thematic map overlays such as rainfall distribution, slope gradient, geological structure, and land use patterns. The results show that areas categorized as having high landslide vulnerability cover 44.02% or approximately 158.69 hectares of the catchment area, while areas with very low vulnerability account for only 0.12% or about 0.79 hectares. Land use conversion, particularly mixed dryland agriculture, has increased landslide risk by reducing slope stability and increasing surface runoff. To address this issue, conservation strategies are recommended, including vegetative measures such as greening 38.51 hectares in settlement areas and implementing agroforestry systems across 218.48 hectares. In addition, structural measures such as three dam retainers and twenty gully plugs are proposed in both protected and cultivation zones to support disaster mitigation and align with regional spatial planning policies.

This study aims to evaluate the actual sump capacity in accommodating mine water discharge, design a sump that fits field conditions, and determine the optimal pump capacity and system at PT Satria Alam Manunggal, Telen Orbit Prima Site. The research methods include field data collection (sump condition, water discharge, and pump capacity) and supporting data (rainfall, geological maps, and pump specifications). The design rainfall was calculated using the Gumbel method with a five-year return period, while water discharge was estimated from runoff, rainfall, and groundwater inflow. The results indicate that the existing sump, with a capacity of 508 m³, is insufficient to accommodate an inflow of 1.210 m³/s. Therefore, two new sumps were designed: the West Sump with a capacity of 38,400 m³ and the East Sump with 78,281 m³. Each sump employs a DnD 150-4H pump with a discharge rate of 480 m³/hour. The West Sump pump can drain water within approximately three days, while the East Sump requires about seven days. The trapezoidal sump design was chosen for its efficiency, structural stability, and effectiveness in sediment (TSS) deposition control, maintaining levels within safe limits. In conclusion, the design of the West and East sumps is considered optimal in accommodating mine water discharge and improving the overall effectiveness of the mine drainage system.

Guaranteeing the geotechnical stability of slopes is an absolute prerequisite for the sustainability of open pit mining operations, considering the potential for multidimensional losses due to slope failure. The specific geological conditions at PIT B1 PT. Pancaran Surya Abadi, which is composed of sedimentary rocks (coal, sandstone, and claystone), are susceptible to degradation and softening, especially due to high rainfall that causes an increase in pore water pressure and a decrease in rock shear strength. This study aims to analyze the stability of highwall slopes using the Morgenstern-Price Method to determine the Safety Factor (SFF) value according to Ministerial Decree number 1827 K/30/MEM/2018, and continued with a semi-quantitative risk analysis. The analysis results show that the initial slope has a static SFF of 0.77 (Not Safe). After redesign, the recommended optimal single slope geometry is: sandstone (Height 5 m, Angle 20°, Berm 5 m) and claystone (Height 10 m, Angle 60°, Berm 5 m). This redesign resulted in a FK of 1.34 (Safe). Sensitivity analysis to groundwater level rise (GTL) showed that the GTL value remained safe (GTL ≥1.30) up to a 30% increase in GTL. However, a 40% to 80% increase in GTL caused the GTL to decrease (1.28–1.21), classified as Medium Risk. A 100% increase in GTL drastically reduced the GTL to 1.05, classified as High Risk. This study emphasizes the need for close monitoring and additional drainage to maintain the long-term stability of slopes under the influence of rainfall.  

A research about study of sandstone slope stability using the Bishop Simplified method in Uu Samarinda has been conducted. This study was conducted to analyze the rebound number values of sandstone slopes, evaluate their stability level, and calculate the safety factor using the Bishop method. The results showed that the rebound number values were 22.34 at point 1, 19.83 at point 2, and 18.07 at point 3. The Uniaxial Compressive Strength (UCS) values at the observation points were 1.90 MPa, 1.62 MPa, and 2.21 MPa, respectively. Geological Strength Index (GSI) evaluation indicated a rating of 80–85, demonstrating intact/massive rock structure, fresh and unweathered rock surfaces, and very good rock quality. Based on the Bishop method analysis, the slope factor of safety in 6.525  with a probability of failure is 0.000%, indicating that the sandstone slope in Ulu Samarinda is highly stable even under external pressures such as heavy rainfall or minor earthquakes. This study provides crucial information on the mechanical characteristics and stability of sandstone slopes in ulu Samarinda, which can serve as a reference for technical planning, geotechnical risk mitigation, and the sustainable development of safe areas.

The 2006 Yogyakarta earthquake, with a magnitude of 6.3 Mw, caused severe structural damage and significant casualties, highlighting the high seismic vulnerability in the Special Region of Yogyakarta (DIY). Tectonic activity in this region is strongly influenced by the subduction of the Indo-Australian Plate beneath the Eurasian Plate and the presence of active faults, particularly the Opak Fault. Local geological conditions dominated by young volcanic deposits and unconsolidated alluvial sediments further enhance seismic wave amplification. This study aims to estimate the Peak Ground Acceleration (PGA) in Prambanan District using the empirical McGuire (1977) attenuation relationship based on parameters from the 2006 earthquake. Analysis was conducted on 113 observation points to map the spatial distribution of ground acceleration. The results indicate that PGA values range from 29.2 to 35.6 gal, with the highest values concentrated in the southern and southeastern parts of Prambanan, characterized by alluvial deposits of the Opak River. In contrast, lower PGA values occur in the northern area underlain by more consolidated young volcanic materials. These findings emphasize the significant influence of lithology and geomorphology on local site response to seismic shaking. The results provide an important basis for seismic hazard assessment and mitigation planning in Prambanan and surrounding areas.

The Special Region of Yogyakarta (DIY) is characterized by high seismic activity due to its proximity to the subduction zone and the presence of active fault systems, particularly the Opak Fault. The 2006 Yogyakarta earthquake revealed significant vulnerability in local building structures and highlighted the complex geological conditions governing seismic wave propagation. This study aims to calculate and map the Peak Ground Acceleration (PGA) distribution in Prambanan District, Klaten Regency—one of the areas closest to the 2006 earthquake source. PGA values were estimated using the McGuire attenuation relationship, based on a moment magnitude of Mw 6.3 and the hypocentral distance to 88 observation points distributed at approximately 900-meter intervals. The resulting PGA map indicates values ranging from 26.7 to 31.7 gal, with a clear spatial trend showing increasing intensity from the northern to the southern parts of the study area. Higher PGA values occur in regions near the Opak Fault and in areas dominated by unconsolidated volcanic deposits of the young Merapi formation. These loose sediments amplify seismic waves, resulting in stronger ground motion compared to areas composed of more compact sedimentary rocks. The spatial pattern of PGA corresponds well with the distribution of structural damage recorded during the 2006 earthquake. The findings emphasize the significant role of local geology and fault proximity in shaping seismic hazard levels. Consequently, this study provides essential insights for disaster mitigation strategies, land-use planning, and structural vulnerability assessment within the Prambanan area.

The limited number of studies examining organizational communication patterns within technical government institutions a research gap, particularly in understanding how communication mechanisms are implemented by public relations units in technical based governmental organizations. This research aims to identify the communication patterns applied by the Public Relations Unit of the Geological Survey Center (PSG) in Bandung, as well as the supporting factors and challenges encountered in its implementations. The study employs a qualitative descriptive approach wih data collected through interviews, observations, and literature review. The findings reveal that the organizational communication pattern operates in multiple directions using both formal communication channels, such as official letters and scheduled meetings through the Nadine system, and informal channels, including face-to-face interactions and digital messaging through WhatsApp. Supporting factors in the communication process include leadership support, a well-defined organizational structure, a collaborative work culture, and the availability of adequate communication facilities and media. However, several constraints remain, including technical and non-tehcnical challenges such as varying work priorities, inconsistents responses times, and unstable network connectivity during field activities.

Blasting and crushing are essential stages in the limestone mining process; however, both stages may contribute to material volume loss due to technical factors and geological conditions. This study aims to analyze the blasted volume, crushed volume, and the amount of volume loss occurring throughout these processes. The research utilizes primary data including blasting geometry, blasting patterns, crushing production, and secondary data such as regional geology and equipment specifications. Based on 15 blasting activities conducted from October to December 2024, the total blasted volume reached 71,691 tons with an average powder factor of 0.23 kg/m³. Meanwhile, the total volume produced from secondary crushing was 71,575 tons. The comparison indicates volume loss influenced by suboptimal fragmentation, rock characteristics, work efficiency of the crushing unit, and operational constraints in the field. The results of this study are expected to serve as a reference for optimizing blasting design and crushing operations to minimize volume loss and improve overall mining productivity.

The stability of slopes in open-pit coal mining in Indonesia is significantly influenced by geological faults, which are a major factor causing slope failures. This study aims to examine the impact of faults on slope stability by conducting a systematic literature review of 25 scientific publications from 2018 to 2025. The results indicate that faults and fault zones consistently reduce rock mass integrity through several mechanisms, including stress concentration in weak zones, the formation of preferential sliding surfaces, amplification of hydro-mechanical effects from groundwater and rainfall, and the reduction of rock strength parameters. Case studies in Kalimantan and Sumatra confirm these mechanisms with slope failures aligning with fault orientations. Kinematic and numerical analyses using the Limit Equilibrium Method (LEM), Finite Element Method (FEM), and Distinct Element Method (DEM) show a reduction in the safety factor (SF) by up to 36% on slopes affected by faults. Practical recommendations include continuous monitoring using Slope Stability Radar (SSR), optimization of slope geometry with angles < 18° in fault zones, groundwater control, reinforcement with anchors and bolting, and UAV-based discontinuity mapping for hazard zoning. This study concludes that managing slopes in fault zones requires an integrated approach combining detailed geological investigation, multi-method numerical analysis, real-time monitoring, and specific mitigation design.

This study was conducted to evaluate the level of conformity between actual mining activities in March 2025 and the monthly sequence design plan at PT Tama Raya's P3000BK14 pit. The evaluation focused on geometric deviations, volume achievement, and changes in field conditions that influenced these discrepancies. The data used included the sequence design, actual topography from the TLS (Low-Scale Land Survey), and weekly production realizations. The results showed significant discrepancies between the planned and actual operations in weeks 2 and 4, primarily in the form of overcuts, undercuts, non-designed contour changes, thinning of the coal seam, and hydrological obstacles such as ponding and unstable drainage. The R2 sequence redesign in week 4 proved to improve the overburden excavation flow but did not fully restore coal access due to persistent geological and water conditions. These findings emphasize the need for more rapid topographic updates, more intensive water handling, and interdepartmental coordination to ensure better synchronization of plans and operations.

This literature study evaluates the accuracy of the Slope Mass Rating (SMR) method for coal mine slope stability in Indonesia through a systematic descriptive synthesis of 25 empirical studies from 2020 to 2025. The objectives of the study were to identify the level of SMR prediction accuracy, factors affecting the method's performance, and modifications required for local Indonesian conditions. The research method involved a systematic search with inclusion criteria for empirical studies reporting SMR and/or Safety Factor (SF) values ​​for coal mines and associated slopes in Indonesia. Quantitative analysis showed a range of reported SMR values ​​between 41 and 96 with a median of 72, while SF values ​​ranged from 1.137 to 4.09 for normal operational conditions. The synthesis results indicated that SMR provides a consistent stability classification for initial slope design and failure mode identification (planar, wedge, toppling), with historical validation showing a correlation of up to 91.23% between SMR-based hazard zoning and actual field events in some cases. Key limitations include dependence on discontinuity data quality, sensitivity to groundwater conditions and tropical weathering, and variation in the interpretation of adjustment factors F1-F4. Modifications such as NAAF23 and integration with numerical modeling have been shown to improve prediction reliability. It is recommended that coal mining practitioners combine SMR with kinematic analysis and limit equilibrium modeling as standard operating procedures, and develop adjustment factors specific to Indonesian geological conditions. Further research should focus on standardizing parameter reporting and cross-site quantitative validation to enable more robust statistical meta-analyses.  

Carbonate rocks are one of the most important geological resources with a significant role in various industrial sectors, particularly as the main raw material in cement, lime, and construction industries. This study aims to review the characteristics, quality, and industrial potential of three major carbonate rock types—limestone, dolomite, and marble—based on relevant scientific literature. The research employed a literature review method using a qualitative-descriptive approach through analysis and synthesis of previous studies. Data were collected from scientific publications addressing the mineralogical, chemical, and physical aspects of carbonate rocks and their implications for industrial performance. The findings indicate that the quality of carbonate rocks is largely determined by mineral composition (calcite and dolomite), chemical purity (CaO and MgO), and the presence of impurities such as silica, alumina, and iron oxides. High-purity limestone rich in calcite is identified as the most efficient raw material for cement and lime industries due to its stable processing behavior and lower energy requirements. Conversely, dolomite with high magnesium content requires process adjustments to prevent excessive MgO formation during calcination. Marble, both in natural and waste powder form, shows promising potential as a supplementary material in sustainable cement production. Overall, this study emphasizes that understanding the mineralogical and chemical variations of carbonate rocks is essential for optimizing their processing strategies and promoting sustainable industrial utilization 

This community service program aims to enhance the understanding of Geology Engineering students at Universitas Sulawesi Tenggara regarding environmentally sustainable mining practices. The education was delivered through lectures, interactive discussions, and local case studies relevant to mining activities in Southeast Sulawesi. These methods were chosen to encourage active participation and ensure the materials were contextually relevant to the students’ local environment and future professional field. The results indicate that students gained new insights into the implementation of good mining practice, post-mining reclamation, and mining and environmental regulations, which fostered greater awareness of the environmental and social impacts of mining. In addition, the program facilitated critical thinking and encouraged students to analyze real-world mining problems from a sustainability perspective. Consequently, this program not only improved students’ environmental literacy but also developed a sense of responsibility and commitment to supporting sustainable mining practices. It is expected that the knowledge gained will influence their future decisions as professionals in the mining sector, promoting a more sustainable and responsible industry.

Reservoir heterogeneity has long been recognized as a critical factor influencing the efficiency of enhanced oil recovery (EOR) methods. Among the techniques applied, cyclic waterflooding is considered one of the promising approaches due to its relatively simple operational design and potential to improve sweep efficiency. This method involves alternating water injection in specific cycles to mobilize trapped oil and redistribute reservoir pressure. However, the variation in geological properties such as porosity, permeability, and fluid saturation creates challenges in achieving uniform displacement, especially in reservoirs with high heterogeneity. Understanding the role of heterogeneity is therefore crucial for optimizing cyclic waterflooding applications. This study applies a literature review approach by synthesizing findings from previous experimental and field studies that evaluated cyclic waterflooding under different reservoir conditions. The analysis compares the performance of cyclic water injection periods across reservoirs characterized by varying levels of heterogeneity. Parameters such as injection rate, water breakthrough time, and oil recovery factor were considered in evaluating the effectiveness of this method. The results highlight that reservoirs with high heterogeneity often experience uneven fluid distribution, leading to early water breakthrough and reduced oil recovery. In contrast, reservoirs with relatively low heterogeneity tend to respond better to cyclic waterflooding, resulting in improved sweep efficiency and higher incremental recovery. Moreover, the optimization of cycle timing and water injection intervals appears to significantly mitigate the negative effects of heterogeneity. In conclusion, the study emphasizes that reservoir heterogeneity plays a decisive role in determining the success of cyclic waterflooding. Tailoring injection strategies based on geological variability is essential to maximize recovery efficiency. Future research should focus on integrating advanced reservoir characterization techniques with adaptive cyclic flooding models to further enhance oil production outcomes.

Gorontalo Province is an area with a high level of disaster vulnerability, both from hydrometeorological disasters such as floods and landslides, as well as geological disasters such as earthquakes. This condition requires an integrated, modern, and sustainable disaster training facility. Unfortunately, until now Gorontalo does not have a representative disaster management education and training center to support community preparedness. This research aims to design a Disaster Management Education and Training Center that not only functions as an education and simulation place, but also integrates green architecture principles to create an environmentally friendly and energy-efficient learning environment. The method used is qualitative descriptive with primary data collection through observation, interviews with stakeholders, and field documentation. Secondary data were obtained from literature studies, disaster architectural precedents, and spatial planning regulatory studies. The design site was chosen in Limboto District with considerations of accessibility, development potential, and geographical conditions. Analysis is carried out on spatial, functional, and climatological aspects to produce an optimal zoning concept and the orientation of building masses according to the tropical climate. The design results show that an area of 19,371 m² can accommodate all space needs with the utilization of KDB of 25.4%. The application of green architecture is realized through the use of environmentally friendly local materials, natural lighting, cross ventilation, solar panels, and rainwater management systems. The simulation facilities for floods, landslides, earthquakes, and fires are designed based on experiential learning so that participants can experience disaster scenarios firsthand. This design is expected to be a model of sustainable tropical disaster architecture, replicate in other disaster-prone areas, and encourage the creation of a disaster-aware culture. This research also opens up further research opportunities related to energy performance evaluation and the application of digital technology in disaster education.