This study investigates the geological diversity of the Tanjung Api region in Tojo Una-Una Regency, Central Sulawesi, with the aim of identifying potential sites for geotourism and geological heritage designation. Through field observations, lithological and geomorphological mapping, petrographic analysis, and structural interpretation, ten geological sites were inventoried. Among them, Gua Kehidupan and Tanjung Api were identified as fulfilling national criteria for geological heritage due to their exceptional features, including fossil-bearing caves, sinkholes, and active gas seeps related to tectonic brecciation. The remaining sites exhibit significant geotourism value, particularly in coastal, volcanic, and sedimentary contexts. Findings from this study highlight the relevance of geodiversity in supporting sustainable tourism and geoconservation. By integrating geological features with educational and community-based values, Tanjung Api demonstrates strong potential to be developed into a geotourism destination that balances scientific significance, cultural relevance, and ecological preservation. The inventory and qualitative assessment serve as a reference for future geoheritage planning and site management. The study recommends involving local stakeholders in the promotion and conservation of these sites to ensure long-term sustainability and community benefits.

Fulfillment of nickel laterite needs for various industrial purposes has become a government plan that must be realized immediately. The sustainability of the nickel laterite supply is the main reason for increasing exploration activities in various nickel laterite-producing areas in Indonesia. Nickel laterite explorations have been carried out in several areas, one of which is in Pomalaa District, Kolaka Regency, Southeast Sulawesi. The ERT (Electrical Resistivity Tomography) method combined with drilling and geochemical data is very suitable for delineating nickel laterite in the subsurface in three blocks. The purpose of this study was to obtain the distribution of nickel laterite in the subsurface and analyze its characteristics. This study used the Wenner configuration and 19 exploration drill points with geochemical assay data. The results of the study showed that there were three zones based on their resistivity values, namely the saprolite zone with a low resistivity value (35 Ωm), the saprolitic rock to boulder zone with a medium resistivity value (35 - 65) Ωm, and the bedrock zone in the form of peridotite rocks with a relatively high level of serpentinization, fracture and weathering, with a high resistivity value ( 65 Ωm). For characterization, the research area is divided into three blocks, namely West, Central and East Block. West block has low Ni content (0.96%) for the saprolite zone and (0.32 - 1.27) % for the saprolitic rock zone, and high (1.65 - 3.24) % for the saprolite zone and (1.35 - 2.27) % for the saprolitic rock zone. In the Central block, the Ni content is low in the saprolite zone of (0.27 - 1.37) % and the saprolitic rock zone of (0.26 - 1.30) %. While in the East Block, the Ni content is low (0.48 - 1.25) % for the saprolite zone, (0.03 - 1.29) % for the saprolitic rock zone, and high (1.34 - 2.94) % for the saprolite zone and (1.31 - 2.84) % for the saprolitic rock zone.

The research area is located in the Tanjung Betung II area, North Kaur, Bengkulu. This research was conducted to determine the geological structure and its relationship with the graben system in the Bengkulu basin by identifying and measuring structural components recorded in rock units. In interpreting deformation mechanisms, this research utilizes surface data obtained from geological structure mapping and lineament analysis based on Digital Elevation Model (DEM) images. Field observations on outcrops have identified five types of structures that have a general northwest-southeast trend, hereinafter referred to as the Manau IX fault, Bunian fault, Tanjung Kurung fault, Aek Kule syncline and Padang Manis fault. This structure may be associated with a graben system that formed in the late phase of basin evolution in the Neogene. Importantly, the structures recorded in the outcrop sequence may be the result of tectonic deformation that occurred during the Late Neogene, coinciding with the start of the Barisan orogeny.

Mangrove forest destruction in Boalemo Regency has increased significantly over the past decade. The condition of mangrove forests has been degraded due to the pressure of population growth, especially in coastal areas. Damage to mangrove forest resources is certainly very dangerous to the ecosystem of fisheries resources, biodiversity and destroys the stability of coastal forests that support the protection of inland and rural agricultural crops. The purpose of this research is to design a model of sustainable mangrove forest resource management strategy in Boalemo District, Gorontalo Province, so that it can be applied as a policy in improving and optimizing mangrove forest resource management efforts in Gorontalo Province. The method used is Interpretive Structural Modeling (ISM). The results showed that there are thirteen sub-elements of program requirements needed to build the model, of the thirteen elements of program requirements there are no sub-elements that occupy quadrant I, in quadrant II there are two sub-elements and in quadrant III there are six sub-elements, in quadrant IV is occupied by five sub-elements which are key elements to build a mangrove forest resource management strategy model.

The clay minerals occurrences can be utilized into various products, including bricks. Brick industry often used the materials taken from the local area. The objective of the research is to identify the lithology of the brick material as well as the mineral consist in the soil or material, including clay mineral. The analysis is carried out in field observation and X-Ray Diffraction (XRD) analysis. The analysis resulting the lithology of the research area is predominantly sandstone and the bricks material is taken from the clayey soil part of from the quartz sandstone lithology. The quartz sandstone predominantly composed by quartz (97%) and plagioclase as minor mineral (3%). The analysis of the clay soil sample in quartz sandstone layer which used as the main component of the brick showing that the minerals composition are mainly quartz (95%) and plagioclase as minor mineral (3%), while the clay mineral that detected is kaolinite (2%). The formation of the kaolinite is interpreted as the result of the weathering of plagioclase trough hydrolysis process. From those data, it is identified that the brick in the research area mainly composed by quartz and clay mineral as kaolinite is formed in just minor abundance.

This research utilizes the Google Earth Engine platform to detect landslides with relatively different NDVI (rdNDVI) methods. The purpose of the research is to improve our understanding of landslide analysis and detection, particularly those that occurred in Sukajaya district, Bogor Regency, Indonesia, on January 1, 2020. This research identifies vegetation changes associated with landslide likelihood using Sentinel-2A satellite image data available on Google Earth Engine. The results show that the rdNDVI method is effective in detecting landslides and can be used to determine areas that may be affected by landslides. This research also evaluates the accuracy of landslide detection by determining the threshold value to determine which areas are affected by landslides, by applying different slope values, the slopes used are slope 10, 15, 20, and 25. Comparing each slope results in a slope of 10 percent and a slope of 15 percent with 90% accuracy making the best accuracy compared to other slopes. The results of this research are expected to help the Regional Disaster Management Agency (BPBD) of Bogor Regency in managing landslides by conducting a careful and accurate analysis of areas that may be affected by landslides.

Salt (NaCl), also known as halite, has a vital role as an essential ingredient in human life and industry. Kebumen Regency in Central Java, especially along the south coast in Ambal District, is one of the area in Indonesia that produces salt, originating from elongated dome-shaped salt ponds, which are the primary source of salt production in the region. Salt quality standards are regulated by SNI 3556:2016, which provides limits for metal contamination such as cadmium (Cd) 0.5 mg/kg, lead (Pb) 10 mg/kg, mercury (Hg) 0.1 mg/kg, and arsenic (As) 0.1 mg/kg. The conditions of seawater and groundwater used in the salt production process have a significant impact on the quality of the salt produced, which can be determined from hydrogeological studies. The results of measuring residents' wells at 43 points show that the depth of the groundwater level ranges from 4.4 to 14.75 meter below sea level. The results of salt analysis from 2 different salt ponds showed Cd levels ranging between 0.0949—0.1001 mg/kg, Pb between 0.5163—0,755 mg/kg, Hg between 0.01198—0.06203 mg/kg, and negative As levels; with water content ranging from 14.43-14.92% w/w and NaCl content between 72.3-85.8%. The analysis of well water and seawater from 3 samples showed Cd 0.0009 mg/kg, Pb 0.0011-0.0098 mg/kg, Hg 0.0001 mg/kg, and As 0.001 mg/kg. The results of groundwater level mapping show that hydrogeological conditions influence the quality standards for salt on the southern coast of Kebumen, especially by the significant grain size factor that carries groundwater and the elements dissolved in it. Meanwhile, salt produced from 2 salt ponds in Ambal District did not meets quality standards based on SNI 3556:2016.

The high land use as area mining has resulted in changes in land cover and impacts the surrounding environment. In 2020, the Semarang City government implemented a Restrictions on Community Activities (RCA) policy to prevent the spread of the COVID-19 virus, indirectly limiting mining activities in the area of the Brown Canyon mine. This study aims to analyze the land cover change in the Brown Canyon mine area linked to the RCA policy. Assessment of land cover change is carried out by land cover classification on multitemporal Landsat imagery using Random Forest (RF) method. Based on the classification results, it was found that there was a change in mining land cover in Brown Canyon which increased by 3.713 Ha when the RCA policy was implemented from 46.305 Ha to 50.018 Ha. Likewise, after the implementation of RCA, there was an increase of 3.510 Ha from 50.018 Ha to 53.528 Ha. The accuracy of land cover classification before RCA was 90.12%. During RCA was 88.18%, and after RCA was 89.94%. Then, if related to the results of the interview data processing, the change in mining land cover that occurred was influenced by mining activities in the study area during the RCA period. So, it can also be said that RCA does not significantly influence mining activities in the Brown Canyon mining area. Several suggestions can be used for further research, such as using high-resolution satellite imagery and having mining area boundary data for each site.

This research aimed to determine the potential of the unconfined aquifer in Gorontalo City based on the landform approach. The landforms in Gorontalo City consist of alluvial plains of lake deposits, floodplains of river deposits, alluvial fans of lake deposits, hills of structural fractures of reef limestones, hills of structural fractures of pinogu volcanic rocks, and hills of intrusive bone diorite. The method used consisted of a meteorological approach in the southern hills of Gorontalo City and a dynamic approach on the plains of Gorontalo City. The calculation of groundwater availability using a meteorological approach is 421.561,67 m3/year in the structural limestone reef fractures hill, 1.198.975,33 m3/year in the structural pinogu volcanic fractures hill, and 373.062,86 m3/year in the intrusive bone diorite hill, with a total of groundwater availability using the meteorological approach, is 1.993.599,87 m3/year. Groundwater availability using a dynamic approach was 2.621.535,19 m3/year or a discharge of 49,26 lt/sec (large) in the alluvial plain of lake sediment, discharge of 17,19 lt/sec (large) in the floodplain of river sediment, and discharge of 16,65 lt/sec (large) in the alluvial fan of lake sediment. The potential value of groundwater using the dynamic method is greater than the meteorological approach because of the amount of evapotranspiration, surface runoff, and crop coefficient.

Monitoring changes in vegetation cover is important for the restoration of ecosystems in the Gorontalo Regency area. The utilization of remote sensing technology makes it possible to detect the dynamics of changes in vegetation cover spatially and temporally. The Terra MODIS satellite image collection in the study area is available in large numbers and sizes. Therefore, cloud computing-based spatial technology support is needed. Google Earth Engine (GEE) as a geospatial computing device is an alternative to cover this shortfall. The aim of this study is to explore the condition of vegetation cover spatially and temporally using the GEE platform. A total of 43 MODIS images in the study area, recording periods 2000 and 2020, were used to quickly and effectively generate vegetation cover maps. The process of downloading, processing, and analyzing data was automated through the GEE interface. The results of the mapping in 2000 and 2020 are shown by maps of vegetation cover in two classes, namely; vegetation and non-vegetation. The accuracy of the vegetation cover map shows good results, namely an overall accuracy of 0.81 for 2000 and 0.85 for 2020. The area of the non-vegetation class increased by 2815.29 ha, and the vegetation class decreased by 2767.31 ha. The map of spatial changes in vegetation cover in the study area is classified into three classes, namely revegetation, devegetation, and unchanged. Based on these results, the extraction of vegetation cover changes in the study area using the GEE platform can be carried out well.