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The study of tholeiitic basalt is a general-classic study from geotectonic MORB, ocean island (OIB), continental rift, volcanic-arcs {IAB or Active Continental Margin (ACM)}. However, the geotectonic study of the tholeiitic volcanic-arcs is still unclear at the moment. In general, the arc tholeiitic is directly pointed to an island-arc volcanic, and the result of google search engine defines no existence of tholeiitic geochemistry which is formed from continental-arc volcanic (ACM). The problem lies in the model of discrimination diagram which is not able to discriminate ACM from the island arc volcanic. The spider diagram shows relatively similar of patterns as well as in the use of the isotope 143Nd/144Nd versus 87Sr/86Sr. Tholeiitic Kebasen pillow lava exhibits a slightly hydrothermal alteration (propyilitic alteration) which consists of plagioclase (labradorite-bytownite), olivine, pyroxene (diopside), hornblende, volcanic glass and other secondary minerals (such as iddingsite, zeolite, carbonate, sericite and opaque minerals). The results of the interpretation using the overlay diagram of Mg# and FeO(t)/MgO, diagram Nb/La vs. La/Yb, the overlaid diagram between the diagram of Zr/Y vs. Zr, newly developed diagram for sedimentary recycling (Th/Ce vs. SiO2) reveal the Kebasen lava is a differentiated tholeiitic rock with relatively low of Mg# (Mg# < 55) which is generated from geotectonic forearc ACM (Active Continental Margin) and involves the sedimentary recycling (Th/Ce > 0.1); furthermore, the trace element constituent is interpreted based upon the melting of oceanic slab (Zr/Y ~ 3). The magmatism of Kebasen lava is potentially formed at temperature of ~ 1240 o C and a pressure of ~ 1.7 GPa at the depth of ~ 56 Km.

Earthquake can be caused by several things, one of which is due to an active fault. To mitigate earthquake disasters that can be caused by the Probolinggo Fault, measurement of the microtremor geophysical method is carried out to analyze seismic vulnerability. In this study, the microtremor measurements were carried out on 30 measurement points. The data obtained from measurements are then processed using EasyHVSR software to obtain natural frequency (f0) and natural amplification (A0) values. This value is then used to create a microtremor microzonation map, which is seismic vulnerability index, based on natural frequency and amplification . it founded that low natural frequency mostly founded on eastern of measurement area, caused by thick sedimentary from Lamongan volcanic. High amplification mostly founded from middle to western area, and high seismic vulnerability index founded on western of measurement area, include Maron and Krucil Sub-district. It means seismic wave can very destructive on those area.

Measurements of the 3D resistivity method have been carried out in the Terung Site, Terung Wetan Village, Krian, Sidoarjo Regency. The study was conducted to determine the distribution pattern of the Terung Site subsurface structure. Many archaeological sites from ancient times have been buried or deliberately buried beneath the surface. The process of searching archaeological sites that have been carried out only based on the results of stories that developed in the community. The 3D resistivity method can be used as a method for conducting site searches. The 3D resistivity method gives the image of the resistivity distribution in a vertical and horizontal cross section therefore to produce a more resolutive image. Based on measurements with the 3D Wenner configuration resistivity method, there is a structured continuity of Kadipaten Terung Site in the depth of 1.5-3.5 meters with resistivity values of 30 Ωm - 80 Ωm.

The monitoring heart rate by vibration sensor based on self-mixing interferometry (SMI) had been done. Experimental schemes and the performance of vibration sensor based on SMI as a function of frequency and amplitude of human heart rate signals had been examined. The vibration sensor consists of a laser diode as a light source (λ = 785 nm) with integrated detector, a mirror as a vibrating target, and a simulated heart signal from ECG generator. ECG generator signals and audio amplifier are adjusted in frequencies of 1-100 kHz. The result showed that the feedback parameter of SMI signal could be identified at frequency 50 Hz. The heart signal was shown clearly at frequency 100 kHz.

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The discovery of the “J” letter-shaped brick structure (also called the Terung Temple) in Terung Wetan Village in 2012 is thought to be a heritage of the Majapahit Kingdom era. However, there is no further research to figure out the distribution of structures in the area. Geophysical surveys with 2D resistivity geoelectric methods-dipole-dipole configuration were carried out in the Site of Kadipaten Terung, Terung Wetan Village, Krian, Sidoarjo Regency to map the distribution of existing subsurface structures. Judging from the location of the Terung Temple, line 1 with the north-south direction on the west side with a length of 62 meters had a resistivity anomaly value of 13.2-60 Ωm at a depth of 1-3.67 m; line 2 with the southwest-northeast direction on the northwest side with a length of 46.5 meters had a resistivity anomaly value of 13.8-75 Ωm at a depth of 1-2.75 meters; line 3 with the northwest-southeast direction on the southwest side with a length of 46.5 meters had a resistivity anomaly value of 12.7 - 75 µm at a depth of 1-2.75 meters; line 4 with the east-west direction on the south side had a resistivity anomaly value of 15-75 Ωm; and line 5 with north-south direction on the east side with a length of 62 meters had a resistivity anomaly value of 15.7-100 Ωm. These anomalies are indicated as subsurface brick structures scattered throughout the research trajectories and it had been the continuity of the Terung Temple into the west and south.

Metode Geofisika memainkan peran yang penting dalam bidang ilmu kebumian, terutama dalam menentukan struktur bumi. Dalam dunia eksplorasi, metode geofisika digunakan untuk mengestimasi sebaran sifat fisika material penyusun bumi tidak terkecuali metode geolistrik. Umumnya, metode geolistrik dilakukan untuk mengestimasi struktur bumi dalam 1D dan 2D. Seiring berjalannya waktu, kebutuhan terhadap data keadaan bawah permukaan yang lebih terkarakterisasi dengan detail dan menerus semakin meningkat. Sementara, harga yang tinggi saat melakukan akuisisi geolistrik 3D terkadang menjadi kendala dalam eksplorasi. Oleh sebab itu, diperlukan hasil penampang yang mendekati kondisi riil-nya yakni pemodelan dalam bentuk 3D berdasarkan data 2D. Untuk dapat memprediksi pola sebaran data di antara titik ukur atau antara penampang, diperlukan aplikasi metode geostatistik. Metode Geostatistik yang digunakan adalah kriging. Data kemudian dilakukan interpretasi secara kualitatif dengan mengintegrasikan dengan kondisi geologinya. Tujuan penelitian ini adalah untuk mengetahui pseudo 3D resis yang dapat menggambarkan bawah permukaan secara 3D dari data 2D. Kombinasi antara hasil dari survei geofisika dan geologi ini dapat menghasilkan persebaran distribusi karbonat di daerah penelitian yakni Kabupaten Tuban, Kec. Jenu. Kemudian, berdasarkan model persebaran karbonat mengindikasikan bahwa lingkungan penelitian ini memiliki jenis karbonat reefal dengan kombinasi batuan gamping dan dolomit.