The 2006 Yogyakarta earthquake was caused by the tectonic movement of the Opak Fault, which is located near the Opak River. This research conducts microtremor data processing and analysis using the Horizontal Vertical Spectral Ratio (HVSR) method and the Inversion method to determine dominant frequency (fo), amplification (Ao), and shear wave velocity to a depth of 30 meters (Vs30) in Opak River area as an effort in earthquake disaster mitigation. The purpose of this research is to compare the Vs30 value of the inversion method using layer parameters according to Standard Penetration Test (SPT) data from previous research and layer parameters according to the number of lithologies. The result presents that the Vs30 values around Opak River are in the range of 183 - 301 m/s and belong to the stiff soil site classification. The comparison shows that the Vs30 values in the two different layer parameters are both still in the stiff soil site classification and have a slight difference in Vs30 values. Thus, the use of microseismic data to determine the Vs30 value is a fast and efficient way to determine the subsurface geology of the study area.

Salah satu tantangan yang sering dihadapi untuk mendapatkan estimasi curah hujan adalah keterbatasan pada data dengan resolusi spasial dan temporal yang tinggi sehingga penginderaan jauh hadir untuk mengatasi masalah tersebut. Pada penelitian ini, data penginderaan jauh telah dimanfaatkan dalam beberapa metode estimasi curah hujan konvensional, seperti Auto Estimator (AE), Insat Multispectral Rainfall Algorithm (IMSRA), Nonlinear Inversion (NI), dan Nonlinear Relation (NR). Tujuan pertama penelitian ini adalah untuk membandingkan keakuratan dari empat metode konvensional untuk menentukan model yang paling sesuai di wilayah Pulau Bali. Kemudian, tujuan kedua dari penelitian ini yaitu pengembangan metode estimasi curah hujan dengan memanfaatkan data dari satelit geostasioner terbaru, Himawari-8/9, dan data curah hujan permukaan dengan menggunakan salah satu algoritma machine learning (ML) yaitu Random Forest (RF). Proses pelatihan model RF dilakukan secara bertahap yaitu (i) penggambaran daerah hujan (ii) pengklasifikasian kelas hujan dan (iii) estimasi curah hujan. Hasil analisis kuantitatif pertama pada penelitian ini diketahui bahwa IMSRA merupakan metode terbaik yang dapat diterapkan untuk estimasi curah hujan di wilayah Pulau Bali dengan nilai rata-rata eror absolut dibawah 1 mm. Pada pengembangan metode yang memanfaatkan pendekatan ML memperoleh hasil yang lebih baik dibandingkan dengan model IMSRA dengan nilai Mean Absolute Error (MAE) sebesar 0,31 yang mengalami perbaikan dibandingkan dengan nilai MAE sebesar 0,94 pada model IMSRA.

The morphological lineament on the surface detected by satellite imagery expresses the geological structure in the form of faults, fractures, joints, and other geological structures. Identification of geological lineaments is useful for analyzing tectonic history, exploring geological resources, and mitigating geological disasters. Exploration of geological resources, one of which is geothermal, continues to be developed to meet the world's growing energy needs. Therefore, the main objective of this study is to extract lineaments using the multidirectional irradiation method from DEMNAS images applied to analyze the permeable zone in the Tulehu geothermal field, Central Moluccas. To optimally identify the geological lineament, lineament extraction is carried out using the multidirectional irradiation method from DEMNAS imagery which has a spatial resolution of 0.27 arcs, which is then quantified lineament density in a grid with an area of 1x1 km2. The quantification result of the highest lineament density is 3.47 km/km2. The permeability zone at the study site is at a lineament density value greater than 1.6 km/km2, which is associated with sedimentary rocks and lithological boundaries. Overall, the multidirectional method of DEMNAS images produces detailed visual images so that lineament extraction can be carried out optimally.

The exploration is the activity of search areas that have the potential natural resources. Such as the exploration of geothermal potential. It can be using of spatial analysis. Spatial analysis can be base modeling of the geothermal potential in the research area. The analytic hierarchy process (AHP) is a fundamental analysis of the modeling data, where the comparison matrix from the analysis like surface temperature, lineament, and eruption center. The result of modeling in the Dieng volcanic complex has identified as the geothermal potential area. The potential area is around of G. Pakuwaja, G. Pangonan-Merdada, and G. Pagerkandang. So that the integration method of the modeling can be used as the method of the geothermal exploration activities.

The Vientiane Province is located in the northern region of Laos and is primarily characterized by a karst environment. This area holds significant potential for geotourism, much of which remains largely unexplored. The blend of natural and cultural attractions makes this region appealing for visitors. Situated in the subduction zone between the Sibumasu and Indochina plates, this area gave rise to the Loei-Phetchabun volcanic belt during the Late Permian to Early Triassic periods. The interaction of these tectonic plates has resulted in a diverse array of rock types, minerals, and unique landforms. Such geological diversity is found in only a few places worldwide, emphasizing the need for conservation efforts, including the designation of this region as a geosite for ecotourism. The aim of this research is to examine the potential of karst landscapes for geotourism. Three selected geosites in the region Muang Met, Kasy, and Vang Vieng districts each have distinct characteristics that highlight different geological features, including karst environments, fault zones, spectacular rock outcrops, fossils, caves, temples, rivers, and cultural centers. We have developed guidelines for geotourism development in this area. As this geotourism study is preliminary, it is currently limited to a few locations, with other potential geotourism sites yet to be explored. To facilitate visitor access, we have created a travel route map and designated stop sites. An overview of each district, including potential challenges to geosite development, is provided in the discussion. Sustainable geotourism development in Vientiane Province is expected to have a positive impact on the local community's social and economic well-being. We hope this paper opens up new opportunities for ecotourism in Laos, potentially paving the way for the region to be recognized as a national geopark.