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Identifikasi bidang gelincir telah dilakukan di Batu Koneng, Kota Ambon dengan menggunakan metode geolistrik konfigurasi dipole-dipole. Tujuan dilakukan penelitian ini yaitu untuk menginterpretasi lapisan batuan bawah permukaan di area penelitian melalui nilai resistivitas guna mengetahui adanya potensi bidang gelincir yang menyebabkan longsor. Data pengukuran dilakukan sebanyak 4 lintasan dengan panjang 110 m yang pengolahan datanya menggunakan software Res2Dinv. Hasil interpretasi menunjukkan bahwa di lokasi penelitian terdeteksi litologi lempung dengan variasi nilai resistivitas 8,77-24,9 Ωm. Sedangkan lapisan lain diduga sebagai batu gamping dengan variasi nilai resistivitas 23,0-70,1 Ωm. Bidang gelincir diduga berupa lapisan lempung yang terdeteksi pada semua penampang lintasan, untuk penampang 1 ditemukan pada kedalaman 1,25 m hingga 6,76 m, untuk penampang 2 ditemukan pada kedalaman 1,25 m hingga 8 m. Sedangkan pada penampang 3 pada kedalaman 1,25 m hingga 11 m dan penampang 4 menjadi lapisan yang paling dalam yaitu 1,25 m hingga 24 m.

The research focuses on analyzing landslides within an area abundant in varying sizes of these occurrences. These landslides happen in consistently loose, deep volcanic sediment, referred to as soil material, over 10 meters thick. The goal is to assess potential sliding plane triggering these landslides within this soil material. To achieve this, a blend of geophysical and soil science methodologies is employed. Geophysical measures, specifically resistivity parameters, discern distinctions within the layers of soil material, determined through geoelectric methods. Additionally, soil science factors like Cation Exchange Capacity (CEC) and silting ease are used to evaluate the layers with pseudo-sliding plane. Findings demonstrate varied resistivity values, CEC, and water content across the different material layers. The N1 layer, situated at a 5-meter depth, exhibiting characteristics of 5Y 8/1 color (leaning toward white/light), shows a resistivity of 8.7 Ωm, a CEC of 54 meq/100g, and high muddiability. Identified as a potential cause of initial landslides or sliding planes, the N1 layer's distinctive values in resistivity, CEC, and water content validate it as an area of concern for potential landslides. These findings confirm that differences in these factors can serve as an early identification for potential landslide-prone areas.

Engineering practice shows that the width of the external foundation pit and the pit in the pit will have a influence on the ways of formation process of the slip surface at the bottom of the foundation pit.Thus, Rankine earth pressure theory based on conventional semi-infinite space is not applicable for calculating the earth pressure acting on the retaining structure for pit-in-pit excavations.Based on the limit equilibrium theory and the fractional force equilibrium method, the theoretical formulas for calculating the passive earth pressure of wide pit and narrow pit are derived, considering the cohesive force of soil and the friction resistance between the retaining structure and sliding soil.For example, the variation trends of passive earth pressure of wide pit and narrow pit in pit condition are compared.The results show that the passive earth pressure considering friction is larger than the passive earth pressure without friction.For both wide and narrow foundation pits, the passive earth pressure with the inner pit is less than that without the inner pit.When there is no inner pit, the increase of the width of the outer foundation pit leads to the decrease of the passive earth pressure, while when there is an inner pit, the increase of the width of the outer foundation pit increases the passive earth pressure.In the narrow foundation pit, the earth pressure decreases first and then increases with the movement of the pit position, and the increase of the pit in the pitplane dimension leads to the gradual decrease of the earth pressure.Thus, the existence of the inner pit will greatly reduce the passive pressure of outer one, and attention should be paid to the existence of inner pits in engineering.

Parangtritis has a rock fall hazard area with a medium to high level of risk. In Parangtritis, there was a large scale paleo-rockslide that involved more than 800 million m3 of rock mass with an area of 1500 m x 2700 m. This is a significant factor in changing the landscape. This research uses 9 Audio-MagnetoTelluric (AMT) primary data points. Using the distance between points 750 m within a 2 km x 2 km study area. The location focused on the western side of the paleo-landslide area in Parangtritis Village. Processing AMT data using the help of MT-INV and RockWorks software. The result of one-dimensional inversion consists of 3 layers. Indicates a low resistivity value (0-10 Ωm) interpreted as beach deposition and sand dune, medium resistivity (50 - 160 Ωm) for Wonosari limestone and high resistivity ( 170 Ωm) for Nglanggran andesite breccias. The average thickness of the first layer is 44 m and the second layer reaches 175 m. Based on the resistivity structure of the AMT data, the interpretation of the boundary contact between the Wonosari limestone and the Nglanggran andesite breccia can act as a slip field in a depth of about 250 m This field is a passive fault field controlled by the Girijati fault in the east of the study area.