Resiko geologi adalah resiko yang terjadi akibat terjadinya proses geologi, atau disebut bencana geologi, seperti gempa bumi, longsoran, banjir, dan erupsi gunung api. Bencana ini dapat melanda permukaan bumi dan mengakibatkan efek kerugian yang tidak kecil, mulai dari lingkungan, aktivitas masyarakat di daerah tersebut, maupun dampak terhadap masyarakat itu sendiri. Saat ini Indonesia sedang beruntun dilanda bencana geologi, seperti tanah longsor, banjir, gempa bumi, erupsi gunung api, dan tsunami. Data statistik menunjukkan adanya peningkatan terjadinya bencana tersebut. Oleh karena itu, diperlukan suatu pemahaman usaha mitigasi bencana, baik sebelum, sedang terjadi atau sesudah terjadinya bencana, termasuk pengetahuan mengenai proses yang menyebabkan terjadinya bencana geologi tersebut. Fokus kegiatan PkM adalah memberikan sosialisasi mengenai kondisi geologi dan potensi bencana geologi yang dapat terjadi di wilayah Ciracas-Jagakarsa-Pamulang, serta usaha mitigasi penanggulangan bencana yang dibutuhkan. Sosialisasi diberikan kepada siswa dan guru SMP Al-Azhar 19 Cibubur, Jakarta Timur. Penyampaian kegiatan sosialisasi dilakukan secara virtual menggunakan aplikasi zoom meeting dan ditindaklanjuti dengan melakukan verifikasi ke lapangan untuk mengidentifikasi potensi bencana di daerah ini. Pelaksanaan program ini telah meningkatkan pengetahuan peserta PkM dalam mengetahui jenis bencana dan mitigasi yang tepat untuk setiap bencana geologi yang berpotensi terjadi di daerah penyelenggaraan PkM.

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In exploration, the investigation of prospective area encounters several barriers of land ownership, budget limitation, and exhausting permit procedures. To speed up the exploration activities of bauxite deposits and bauxite characteristics, grades of the gap areas should be simulated based on the available test pit data sets. This study aims to address the limitations and to optimize the exploration boundaries using the R project for statistical computation. R data analysis weaves the framework of kriging that required information from the adjacent data. This study utilizes the geochemical data of Al 2 O 3 , Fe 2 O 3 , SiO 2 , and TiO 2 from 296 test pit sampling points. The geochemical data used for R analysis were taken from bauxite horizon, while the other mineralogical properties were taken entirely from the exposed bedrock and test pit data. To verify the result of R analysis, recent data of the simulated area were used as a comparison. The R result shows the prediction value is slightly below the actual value of Al 2 O 3 . The kriging simulation of Al 2 O 3 was correlated with test pit and mineralogical characteristics of samples. This reveals the predicted value of simulation closely represents the true value of Al 2 O 3 grades. Extrapolation results of Fe 2 O 3 and RSiO 2 with regards to Al 2 O 3 grades suggest that higher grade of bauxite underwent desilication and deferruginization as evidenced by a high value of Index of Lateritization. It can be inferred that this attempt points out the advantages of a quick and reliable projection of bauxite laterite deposits from the limited parameters

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3D inversion modeling of subsurface based on gravity anomaly data and magnetic anomaly data used for identification hydrocarbon potential in “x”. Where in the study area there are up dome structures that indicate some possibilities, including igneous rock intrusion, carbonate build up and also mud diapir. 3D inversion modeling of gravity and magnetic anomaly data correlated with two seismic section which available in study location. 3D inversion model is performed on the residual anomaly data on the gravity model and 2D in the magnetic anomaly. The result of 3D inversion modeling of gravity anomaly data shows that the peak up dome is at a depth of study located around 800 meters from the surface, this result corresponds to spectrum analysis and depth on the seismic cross section, while the density value of the up-dome body is approximately 2.78 g/cm3. While on the magnetic anomaly that has been done, structure of the dome indicates an intrusion structure with anomaly susceptibilities show the structure of igneous rock.