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Shear Wave Splitting is an application of seismic wave to analyse the anisotropy level of a certain medium. Generally, shear wave propagation through a rock formation will be polarized (φ) into two parts especially when the medium structures are different, such as fracture. The polarized shear wave which is perpendicular to fracture will propagate slower than the wave that propagates parallel to the fracture. The delay time (δt) of both wave is proportional with the fracture intensity along the wave propagation from the source to the station. The description regarding fracture orientation can be obtained by analysing both Shear Wave Splitting parameters (φ and δt), and this information is adequately important in geothermal exploration or exploitation phase at Mt. Amiata. Based on the result of this research, the micro earthquake source is focused on the east to the south area and spread along 3 earthquake stations. The existence of micro earthquake source is mainly focused at the depth of 1 to 4 km. In addition, the polarization direction of each earthquake station at the geological map shows a dominant fracture orientation consistently at NW-SE. All of the three stations also show that the polarization direction is integrated to the local fault existence in the subsurface. Furthermore, the research shows that the high intensity fracture distribution occurred at MCIV station area in the southern part of research location. Meanwhile, the low intensity fracture distribution occurred at ARCI and SACS station area in the western and the eastern part of research location. The high value of fracture intensity accompanied by the high amount of structure intensity, strengthen the prediction of the high anisotropy existence which potentially tends to the high permeability presence at the area.Keywords: shear wave splitting, anisotropy, fracture, geothermal, polarization direction, fracture intensity.

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The research aims to delineate the groundwater basin in Bandar Lampung from gravity anomaly. Field data acquisition was carried out at 403 points with a spacing of 2-3 km, covering the Bandar Lampung and surrounding areas. Data processing through gravity data corrections, namely drift, tide, Free Air, Bouguer and Terrain using Geosoft Oasis Montaj 8.3. The Bouguer density used is 2.67 gr/cm3. For the anomaly separation, spectrum analysis and regional and residual anomaly separation were carried out, whereas 2D modeling was carried out by forward modeling. This basin boundary analysis is based on gravity residual anomaly patterns, gravity Second Vertical Derivative (SVD) analysis, and 2D gravity modeling. There are two low residual anomaly patterns (-22 to -5 mGal), where the boundaries of the basin can be clearly delineated from SVD analysis. This 2D model shows layers with a density of 2.3 gr/cm3 which are the Young Volcano Formation (Qhv) and the Lampung Formation (QTl) which have depths of up to 1.0-1.5 km. This Groundwater Basin correlates well with the hydrological pattern with a water discharge of 5 to 100 l/sec.

Research on the Palu earthquake in the period of August to October 2018 has been carried out in the Palu Koro Fault (PKF) zone with a hypocenter of 5-20 km. This study aims to determine the fractal dimensions of these earthquakes based on the relationship between logarithmic frequency and earthquake magnitude correlation introduced by Gutenberg-Richter. Statistical correlation between logarithmic frequency and earthquake magnitude was calculated using the inversion approach. Based on the calculation results obtained fractal dimension value of 1.0378, which describes the seismicity pattern at a depth of 5-20 km. It indicates that the earthquakes triggered by the movement in rupture segments which seen as points along the PKF zone.

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