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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.

Magnetotelluric (MT) research was conducted to map the fault structure in the western part of East Java. The advantage of the magnetotelluric method is its deep penetration because it propagates at a low frequency so that it can detect resistivity anomalies that are thought to be faults. The measuring path of the magnetotelluric method covered the Surabaya and Gresik areas. Research conducted in densely populated areas thus it requires a noise reduction process to improve the quality of the data. Performing the robust processing with Rho Variance parameters and editing XPR is an effort to reduce noise and to improve the quality of magnetotelluric data. The robust processing result of 5 (five) sounding MT data using the Rho Variance parameter can improve the quality of magnetotelluric data by increasing the coherence value of 2.128% (MT01), 2.804% (MT02), 2.378% (MT03), 3.508% (MT04), and 3.129% (MT12). Meanwhile, the editing XPR process can increase the coherence value of 0.184% (MT01), 7.155% (MT02), 9,364% (MT03), 0.784% (MT04), and 0.628% (MT12). Escalation of coherence value by implemented the Rho Variance and Editing XPR means that two methods are sufficient effectively to raise the confidence level of MT data processing and interpretation result.

The pull-up effect is the condition of lithology elevated in seismic imaging because of rapid seismic wave propagation through carbonate build-up on it. Pull-up effect conditions can lead to misinterpretation, so it needs to be corrected until the actual geological conditions are obtained. This research was conducted in the JAX-field working area of PT Pertamina Hulu Energi ONWJ. The target reservoirs of this study are in the Main (Upper Cibulakan) Formation under the Carbonate Parigi Formation. The reflectors of the target reservoirs show pull-up effect in time domain seismic data. Thus, building a velocity model for velocity anomaly correction is needed to reduce uncertainty for structure maps and oil in place calculation. The method of correcting the pull-up effect in this study uses three variations of the velocity model: variation structurally controlled model, variation RMS velocity with well control, variation calibrated RMS velocities model. The three variations of the velocity model result can correct the pull-up effect on JAX-Field. Velocity model with variation RMS velocity with well control had the lowest error with 17,31 feet average of depth difference with actual depth from well. Based on three velocity models, the value of original oil in place on the JAX-32 reservoir surface had a range of 59,14-84,59 mmbo, while on the JAX-35A surface has a range of 27,77-31,23 mmbo. These values can be considered in reserve calculation sensitivity.

Ancient civilizations in Jombang left many historical relics in the form of temples, artifacts, and other archeological sites. Kedaton site is one of the newly discovered archeological sites. This site is buried under a few meters thick of Mount Kelud’s pyroclastic flow. Therefore, the distribution patterns of the site is needed to improve the excavation plan in order to maintain the structure of the site. One of the technical approaches that can be applied to map the site’s distribution in detail is geophysical survey. Geomagnetic method is a method commonly used in the case of archeological site investigations because of its non-destructive nature. The mapping process on Kedaton site is conducted by applying geomagnetic survey that utilizes physical parameters in the form of magnetic susceptibility. The reduce to pole filter is applied to magnetic data processing to aid interpretation, coupled with horizontal gradient method and analytic signal method further clarify the boundaries of magnetic anomaly sources. Reduce to pole filter indicates that the site’s brick detected as moderate to high magnetic anomaly values (more than 450 nT). This research succeeded in mapping clearly the boundaries of the site with an area of up to 6000 meters2 with the shape of the site resembling a building with several chambers. The main chamber is in the north which is the widest chamber, and small chambers are found on the south side.

Some heavy metals of Cd, Cu, Pb, and Hg polluted in Segara Anakan Cilacap, but no information on a specific heavy metal pollution in this area and an edible mud crab of Scylla serrata. The research aimed to know their distribution in this area and their accumulation of heavy metals from waters and sediments to Scylla serrata. The study was done using a survey method with purposive random sampling at six stations from Station SA-2-28 and SA-3-46 (with a high percentage mangrove canopy cover) to Station SA-2-24, SA-3-35, SA-1-10, and SA-3-16 (with a low percentage mangrove canopy cover). Three replications were done in the dry season conditions from July to September. The researcher took all samples with the water sampler tool, sediment core, and baited trap for sampling. Then, they were analyzed using Atomic Absorption Spectrophotometry (AAS) method. The result showed that the lowest heavy metals were at Station SA-2-28 and SA-3-46 and followed by Station SA-2-24, SA-3-5, SA-1-10, and SA-3-16 due to the high percentage of mangrove canopy cover, while the reserve order was due to the increased pollution in east side areas of Segara Anakan Cilacap. The heavy metal accumulation of Cd, Cu, Pb, and Hg has occurred from waters and sediments to Scylla serrata.

The subsurface geological condition of East Java is an area that is crossed by an active fault geological structure. The National Earthquake Center revised the Indonesian Earthquake Hazard and Source Map of 2017 with the discovery of new active faults surrounding the Kendeng Zone, East Java. This research was conducted using Magnetoteluric (MT) method which has high penetration therefore it was able to map the geometry of active deep fault structures beneath the surface. Measurements were made at 11 measuring points focusing on the Blumbang Fault (M6.6) in Lamongan District. 4 (four) lines were made from 11 existing measuring points. The lines were then modelled in 2D to describe the distribution of subsurface resistivity. The results showed an anomaly with low resistivity value which was indicated as Blumbang Fault in 4 section models. Section of line 1 and 2 indicated a fault in the NS-SE direction continuity to the northwest which became deeper to the south from 6 km to 9 km. Lines 3 predicted the fault with low resistivity value (

Jambi Province has an extraordinary treasure of Genetic Resources. This fact is supported by geographic conditions and supported by four national parks. Jambi Province has supported the use and protection of genetic resources, one of its efforts is to establish a Regional Commission on Genetic Resources. As a chief executive of the daily implementation of this commission, Research and Regional Development Board (Balitbangda) through its duty conducting study and research activities because if not managed well so the availability of genetic resources be threatened. This study aims to determine the role of Balitbangda of Jambi Province to preserve the genetic resources in Jambi Province. This research is qualitative research with a phenomenological approach. This research was carried out at Balitbangda Jambi as a chief executive of the daily implementation of The Regional Commission in Jambi Province. The sampling technique using purposive random sampling and types of data used are primary and secondary data collected by in-depth interviews and document searches. The results showed that the role of Balitbangda in Jambi Province in its efforts to preserve genetic resources were conducting research and development activities, active in the Regional Commission of Genetic Resources, cooperated with competent institutions, conducted seminars on the results of studies, socialized to teachers/education staff in the district/city about the genetic resources, and supported the acceleration of registration of geographical indications of Pineapple Tangkit Baru. The roles were still not optimal because there are still obstacles in the implementation.