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The Muria Peninsula is a complex of volcanic activity located in the back arc of Sunda, which includes Kudus, Jepara, and surrounding districts. Volcanic activity on Mount Muria, can be used to study geological conditions, which were closely related to chemical elements. The presence of chemical elements in the river sediments of the Muria Peninsula was also influenced by anthropogenic heavy metal pollutants present in river deposits along the Muria Peninsula. The purpose of this study was to determine the relationship between the geological conditions and the environmental conditions of the Muria Peninsula with the anomaly of track elements and heavy metal elements. The methods used in this research were the pick test method, XRF geochemistry and the results were correlated into a geochemical anomaly map. The results showed that there were trace elements anomalies of Ce and Nd in Jepara area which were influenced by Muria shoshonitic rocks. Anomaly of Cu element was found in Jepara area, anomaly of Mn element was found in Jepara and Demak, and anomaly of Zn element was found in Jepara and Demak. Anomaly of Cu, M,n and Zn elements were high in upstream area and caused by land use of dry agriculture, paddy fields and settlement areas.

Ngempon Temple is one of the historical sites around the Mount Ungaran area. Ngempon Temple is the result of Hindu civilization in Indonesia which was built in the VIII-IX century. This research was conducted in the Ngempon area because it is necessary to conserve historical sites associated with geological sites in the study area. This study aims to determine the geological aspects that have the potential to become geotourism sites in the research area. The methods used are geological mapping for field data collection and petrographic analysis to determine rock characteristics. There are several sites including historical sites and geological sites in the vicinity of Ngempon Temple, namely Ngempon Temple, Diwak Waterfall, and Derekan Hot Springs. The lithologies found in the research area are claystone, tuff sandstone, basaltic andesite breccia, and andesite breccia. The volcanic rock in the research area is formed by Mount Ungaran activity during Lower Pleistocene until Holocene.

Kayen District, Pati Regency is a karst morphology area composed of karstified limestone with geotourism potential, established as Karst Landscape Area. As basis for infrastructure development in geotourism area, a database of geosites need to be built to make sure it is available for government and public. The method used is field observation, interviews and SWOT analysis. Morphology of this area is divided into conical karst hills and the karst alluvium plains. The lithology of the research area are reef limestone, clastic limestone, and alluvial deposit. Inventory managed to identify potential geosites such as hills, cliffs, caves, and springs; five existing geosites have been developed and six locations are new geosite recommendations. From the SWOT analysis, it is known that this location has the strength that is the uniqueness of morphology from karstification results, the weakness is geotourism concept is still not yet understood by local residents, the opportunity is the minister's decision regarding the Sukolilo Karst Landscape Area and the threat is lack of geological protection at the research site. The geotourism and geotrack map will serve as geospatial information and further recommendation for government to prioritize the infrastructure development in this area.

West Kalimantan has very large bauxite resources, reaching 2.07 billion tons, equivalent to 57.32% of the total bauxite resources in Indonesia with bauxite reserves of 0.84 billion tons or equivalent to 66.77% of the total national mineral reserves. The researched area covers Sompak District and surrounding areas, Landak Regency, West Kalimantan. This research aims to determine geological conditions, laterization, and characteristics of laterite bauxite in the studied area. Methods used in this research are geological mapping, lateritic mapping, and petrographic and geochemical analyses. The lithology of the researched area is composed of granodiorite, porphyry quartz diorite, granite, porphyry andesite, porphyry basalt, alluvial, and swamp deposits. Laterite profiles in the researched area generally consist of topsoil, latosol, bauxite, and clay zone. The laterite bauxite derived from granodiorite is classified as a medium grade, laterite bauxite from porphyry quartz diorite is classified as high-grade bauxite, laterite bauxite from andesite porphyry is classified as low-medium grade bauxite, and laterite bauxite from porphyry basalt in the studied area is classified as high grade bauxite. Laterite bauxites in the researched area were formed from weathered parent rocks which were intermediate - alkaline igneous rock. [ABSTRACT FROM AUTHOR]

The research area is a part of South Serayu Mountain zone, specifically Bregada Kulon Progo. The Bregada Kulon Progo is a product of volcanic activity in the past, which can be seen by the volcanic rock called Old Andesite Formation. The end of the volcanic activity is characterized by the deposition of carbonate rocks which were part of Jonggrangan Formation and Sentolo Formation. The lower part of Sentolo Formation is composed by the mix of carbonate and volcanic materials. The research is carried out by two methods. The first is field method, which is implemented by geological mapping and rock sampling. The second is laboratory method, which is implemented by petrographic method. The petrographic method is implemented by making thin section of the rocks, then observing the thin section with polarization microscope to determine the composition of the rocks. The rock samples are mainly from the lower and middle part of Sentolo Formation, which probably still got the influence of volcanic activity. The benefit of the research is knowing the influence of volcanic activity in the carbonate rocks of Sentolo Formation. The presence of volcanic materials in the lower part of Sentolo Formation, can be predicted by two processes. First, the volcanic activity supplied those materials directly, and second, from the rework of the volcanic materials then mixed with carbonat materials of Sentolo Formation.

Rembang Madura Kangean Sakala (RMKS) fault zone and W-E structures of Kendeng Zone are the main structural elements in back arc basin, East Java, Indonesia. There are many perspectives about the overpressure zone at the basin. This research focus on the overpressure zone that related with formation and tectonic evolution. The study infer that high overpressure is explained by regional and local mechanisms. The results of analysis of log derived porosities at Karang Mudi-1 (KM-1) well indicate that high overpressure and overpressure was Neogen Formation (Mundu, Wonocolo, Ngrayong). Pore pressure prediction at KM-1 exerted Eaton’s method. There are two overpressure zones at depth 2.680 – 4.900 fTVD (B Zone) and 5.600 – 8.400 fTVD (D Zone). High overpressure D Zone are regionally caused by flexural structure (anticline and fracture) from transpression setting (West – East RMKS). High overpressure in KM-1 is transpression setting early which the overpressure follow the pop-up boundary. Area of high overpressure always related with fault thrust. Static mechanism is possible in the present day interplate stress field. Present the maximum horizontal stress was NEE – SWW. Local mechanisms occurs illitization at D zone from depth 6.800 – 8.400 fTVD. D Zone is unloading mechanism (illitization and lateral transfer open fracture).

Sentolo formation that is included in the Kulon Progo stratigraphic series has a wide distribution. Although there have been a number of studies on it, more detailed research is needed, as there are still many unexplored outcrop locations. Moreover, there are still a lot of questions about the stratigraphic relationship between Sentolo Formation and Oligocene-Miocene volcanic series of Kulon Progo. Based on this background, this study is focused on the existence of foraminifera fossil in Sentolo Formation as an indicator of palaeoecological conditions at the time Sentolo Formation was deposited. This research is very important to get a detail understanding about the indicators that are influential at the time of deposition process of Sentolo Formation in research area. Based on palaeoecological analysis, the palaeoecology at the time Sentolo Formation deposited was normal marine continental slope waters. Meanwhile, the community structure of foraminifera indicates a stable water conditions in a marine environment that was not disrupted by volcanism, so it becomes a good factor for the growth of foraminifera. Whereas the presence of volcaniclastic material mixed with carbonate which is occurred in the lower part of Sentolo Formation were interpreted as reworked of older volcanic rock.