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The Tehoru earthquake occurred due to the release of stress in rocks. There is a release of energy as an earthquake as a result of the rock elasticity limit has been exceeded because the rock is no longer able to withstand the stress. One method to determine the distribution of earthquake stress is the Coulomb stress change method. The study aimed to determine the DCS of the Tehoru earthquake, Seram Island, and the effect of the main earthquake stress release on aftershocks. The research results show that the DCS distribution of the Tehoru June 16, 2021 earthquake is shown with negative lobes and positive lobes. The negative lobe is found in an area that is perpendicular to the fault plane and has been identified as having experienced relaxation, so there may be still aftershocks with stress values ranging from (0.0 – 0.3) bar. The dominant positive lobe occurs next to the southern end of the fault plane, too much located in the area of increasing Coulomb stress with values ranging from (0.2 - 0.6) bar

One of the areas of Ambon Island that contains prospects for laterite nickel deposits is the Tanitabuntal hills, Amahusu Village, Ambon City. This laterite nickel deposit is interpreted to originate from the weathering of ultramafic rocks. This mining material is not known with certainty, so no exploration has been carried out. Field measurements used the geoelectric resistivity method with a dipole-dipole configuration. This method is used to identify the presence of laterite nickel deposits. Geoelectric surveys are used to indirectly determine the presence and dimensions of subsurface geological material layers based on the resistivity cross-sectional profile. Then, rock samples are tested in the laboratory to determine the mineralogical characteristics of the constituent structures. The results of the interpretation of the rock resistivity values obtained ranged from (20-400) Ω.m. The presence of laterite nickel deposits consisting of limonite and saprolite zones at a thickness of 7.5 m. The research area is dominated by Serpentine minerals with an abundance of more than 77.0 %, and other profusions in the form of Opak, Epidote, and Sericite minerals as associated minerals that fill the fracture.

The investigation of landslides applying various methods has been receiving increased attention in recent years. This study was aimed at assessing the estimated distribution of landslide movement using an energy conservation formula in a lumped mass model to obtain velocity and travel distance estimations, in combination with an inverted resistivity model for estimating the Amahusu landslide volume. The research location was in the Amahusu hills of the Nusaniwe subdistrict, Ambon, Indonesia. A survey was carried out using GPS and a geoelectric resistivity method with the Wenner-Schlumberger configuration. The results of the study provide a characterization of this rotational type landslide. The estimated landslide volume was 70,954 m 3 and the estimated potential landslide volume was 50,603 m 3 . This mass moved 303 m away from the original location, with an estimated maximum velocity of up to 21.25 m/s. The displacement pattern of a landslide mass is primarily controlled by the geometry of the sliding plane. The geometry of the sliding plane causes different types of movement, based on which the possible occurrence of a future landslide can be predicted .