Gravity Field Interpretation for Subsurface Structure Identification in a Tiris Geothermal Area, Indonesia

Resistivity characterization of the Arjuno-Welirang volcanic geothermal system (Indonesia) through 3-D Magnetotelluric inverse modeling

This study aims to understand the differences in the characteristics of volcanic and non-volcanic geothermal systems on Java Island, specifically in the Central and East Java geological zones. The analysis is done through geochemical studies of anion-cation, isotopes (δ¹⁸O and δD), and rare earth elements. Volcanic systems are centred around the Quaternary volcanic regions, such as Dieng, Ungaran, and Ijen. In contrast, non-volcanic systems are found in the Kendeng Zone, South Serayu, and the Southern Mountains. The research results show that volcanic geothermal systems are dominated by chloride water with high Cl⁻ ion concentrations due to direct interaction with magma. These systems are rich in rare earth elements, such as Sr, Ba, and Eu, reflecting high mineralization potential. In contrast, non-volcanic systems are dominated by bicarbonate and sulfate waters, which form due to tectonic activity and geothermal gradients. Isotope analysis reveals that volcanic systems are influenced by a mix of meteoric, hydrothermal, and magmatic waters, while non-volcanic systems are primarily dominated by meteoric water. These findings reveal different geothermal fluid dynamics in the two systems, reflecting their respective geological characteristics. The novelty of this study lies in the comprehensive comparison of the chemical and isotopic characteristics of volcanic and non-volcanic geothermal systems, as well as the identification of rare earth elements potential in both systems. This research contributes significantly to the diversification of renewable energy, exploration of rare minerals, and the development of sustainable geothermal energy to support national strategies toward net-zero emissions.

In order to examine the spatial variability of the aerosol characteristics across the Brahmaputra valley, a land campaign was conducted during late winter (February 3–March 2) 2011. Measurements of particulate matter (PM, PM10, PM2.5) and black carbon (BC) concentrations were made onboard an interior redesigned vehicle. The length of the campaign trail stretched about 700 km, covering the longitude belt of 89.97°–95.55°E and latitude belt of 26.1°–27.6°N, comprising 13 measurement locations. The valley is divided into three sectors longitudinally: western sector (R1: 89.97°–91.75°E), middle sector (R2: 92.5°–94.01°E) and eastern sector (R3: 94.63°–95.55°E). Spatial heterogeneity in aerosol distribution has been observed with higher PM10 and PM2.5 concentrations at the western and middle sectors compared to the eastern sector. The locations in the western sector are found to be rich in BC compared to the other two sectors and there is a gradual decrease in BC concentrations from west to east of the Brahmaputra valley. Two hotspots within the western and middle sectors with high PM and BC concentrations have been identified. The associated physico-optical parameters of PM reveal abundance of PM2.5 aerosols along the entire valley. High population density in the western and middle sectors, together with the contribution of remote aerosols, leads to higher anthropogenic aerosols over those regions. Spectral Radiation-Transport Model for Aerosol Species (SPRINTARS) slightly underestimates the measured PM10 and PM2.5 at the eastern sector while the model overestimates the measurements at a number of locations in the western sector. In general, BC is underestimated by the model. The variation of BC within the campaign trail has not been adequately captured by the model leading to higher variance in the western locations as compared to the middle and eastern locations.

Purpose: the studies of the Proletarskiy reservoir is to use the Novo-Manych dam in regulating the operation of the western and eastern sections with a water regulating structure between them. Materials and methods: the issues on use and regulation of water resources of the Proletarsk reservoir are considered, including the Novo-Manych dam, which divides the reservoir into the western and eastern sections. Results. The western section of the Proletarskiy reservoir is located between the Proletarskiy hydroelectric complex and the Novo-Manych dam and is a stretch of about 20 km. Under normal operating conditions, water flows from the western section to the eastern one through the water regulating structure in the Novo-Manych dam. At the same time, the main amount of water enters the western section along the river Egorlyk, it is discharged through the drain of the Proletarskiy hydroelectric dam into the Veselovskoye reservoir. The eastern section of the Proletarskiy reservoir is limited by the Novo-Manych dam on the western side and a blind dam on the eastern side. According to the initial project, the water resources of the Proletarskiy reservoir were used for shipping, irrigation, fisheries, and hydropower. The actual use of the reservoir's water resources for navigation is practically absent, irrigation is not performed, the fishery has lost its importance, and the hydropower industry has been out of service. Only recreation is used: the sanatorium “Manych”, about 30 hunting farms, the “Rostovsky” and “Chernye Zemli” reserves, the natural monument “Primanychskaya steppe”. The network of reservoirs and Manych-Gudilo lake is a wetland of international importance as a habitat for waterfowl. Conclusions. The issues of the use and regulation of water resources of the Proletarskiy reservoir and the Novo-Manych dam, dividing the reservoir into the western and eastern sections are considered.

Lithostratigraphy, microfacies and paleogeography of the shallow marine Middle Limestone Member of the Early Eocene Rusayl Formation, Oman: Relationship to the Early Eocene Climatic Optimum, sea-level changes and regional uplift

Development planning and tourism are an inseparable part of the integrated development unity in Indonesia. SDGs demands for sustainable development are a challenge in themselves. Development in Indonesia has an integrated planning system from central to regional government and from region to center. Integrating the SDG's focus as a mandatory aspect of sustainable development, tourism is included as one of the development items. This research uses qualitative methods by comparing the two regions. The concept of sustainable tourism development, namely Pro-Economic Prosperity, Pro-Environmental Sustainability, Pro-Social Justice and Pro-Environment, has not fully answered new problems such as capacity which results in a saturation point in development and change. in leadership in a democratic system for 5 years, and unforeseen circumstances such as natural disasters. Tourism development has been discussed a lot, and some things refer to new variables. This research aims is to find a new concept of sustainable development. Informants from this research used purposive sampling with the informant being the Head of Research and Development at BAPPEDA and the Head of the Tourism Development Section at the Tourism Office in two different regions, namely Batu City and Probolinggo Regency. Primary data uses interview results and secondary data uses official documents from regional organizations. This research produces three new variables in Sustainable Development, namely political sustainability, disaster preparedness, and visitor capacity as aspects that need further consideration. This variable is a new concept in the development of Public Administration Science, especially in the field of Sustainable Development.

Cross-basin heterogeneity in lanternfish (family Myctophidae) assemblages and isotopic niches (δ13C and δ15N) in the southern Tasman Sea abyssal basin

The paper analytically discusses certain palaeoecological criteria in the reconstruction of Lower Miocene (Aquitanian-Burdigalian) palaeobiogeography of the Indian subcontinent. The period is characterised by major marine transgressions and a prolific marine invertebrate and terrestrial vertebrate faunas. Faunal affinities of molluscs from western (Sind-Baluchistan) and eastern (Garo Hills) sectors are distinct and different. Molluscs of Garo Hills show affinity to Burmese species, whereas Sind-Baluchistan species shows similarity to that of the Mediterranean region. Marine molluscs resemble with the present-day taxa of the Arabian Sea and Bay of Bengal, where more than 35% species are common. This similarity is also evidenced by marine elasmobranchs, where approximately 33% species and 86% genera are similar to that of the Recent taxa. Terrestrial mammals show an intermingling of southern U.S.S.R. and African forms along with the presence of probably some groups belonging to the Indian subcontinent. Angiosperms are the dominant group. The Lower Miocene floras of the eastern and the western sectors are entirely different. The palm,Sabal major andPinus are reported from various localities. The climate in the western sector and South India was tropical, whereas in the eastern sector, it was variable. The Lower Miocene period is also marked by the contraction of Sindhu Sea, Bangla Sea and the Burmese Gulf southwards resulting in the final disappearance of the sea by the Pliocene.

Nature and Classification of Geothermal Resources

One of the most persistent rain-making events over East Asia is the development of an early summer monsoon trough (Mei-Yu) which extends from southeastern China to southern Japan. This work studies the structure and vorticity budget of a Mei-Yu system for the period 10–15 June 1975. Subjectively analyzed grid-point data are time composited with respect to the trough axis along three cross sections over southeastern China (western section), southern East China Sea (central section) and southern Japan (eastern section), respectively, during the mature and decaying stages of the trough. The results indicate that the structure of the eastern and central sections resembles a typical midlatitude baroclinic front with strong vertical tilt toward an upper level cold core and a strong horizontal temperature gradient. On the other band, the western section resembles a semitropical disturbance with an equivalent barotropic, warm core structure, a weak horizontal temperature gradient, and a rather strong horizontal wind shear in the lower troposphere. Cumulus convection activity south of the 850 mb trough is significant in all three sections and contributes substantially to the thermally direct secondary circulation, but the large-scale organizing mechanism differs from one section to another. In the eastern and central sections it is mainly due to differential vorticity advection while in the western section it is due to Ekman pumping (CISK). The generation of cyclonic vorticity is counteracted by cumulus damping in the eastern section and by boundary layer friction in the mountainous western section.

The Lower Cretaceous Leza Formation is an essentially carbonate unit deposited at the northernmost active margin of the Cameros Basin (N Spain) under an extensional tectonic regime. This unit is composed of freshwater, marine-influenced, marginal-marine and hypersaline marine carbonate facies, interbedded with variable amounts of alluvial deposits, mainly derived from the erosion of the Jurassic substrate. 87Sr/86Sr, δ18O and δ13C analyses were obtained from carbonate facies of the Eastern and Western sectors of the basin. δ18O values follow the expected trend in both sectors: they are more negative (down to − 7.9‰) in freshwater carbonates and more positive (up to + 2.8‰) in marginal-marine to hypersaline facies. However, independently of the seawater or freshwater influence, in the Western Sector the 87Sr/86Sr values (0.707373–0.707801) are significantly lower and closer to the published Lower Cretaceous seawater 87Sr/86Sr ratios, than those of the Eastern Sector (0.707988–0.709033), where the overall marine influence was relatively high and the alluvial input low. These data strongly suggest that 87Sr/86Sr ratios were mainly controlled by those of the riverine freshwater arriving to the coastal and marine areas after the weathering and erosion of the Jurassic carbonates or siliciclastic rocks, in the Western and Eastern sectors, respectively. Thus, data indicate that, in coastal and shallow marine carbonates, the influence of the riverine water on the 87Sr/86Sr ratios should be systematically evaluated. This is particularly necessary in active tectonic settings, where the uplifted areas are significantly prone to weathering and erosion and where alluvial fan systems commonly developed, eventually discharging into coastal and shallow marine areas.

Heteroptera is a worldwide distributed group of insects inhabiting both terrestrial and aquatic habitats and has an important ecological role. A survey of aquatic and semiaquatic Heteroptera from Cuba is provided based on literature reports and field collections. General data on species geographical distribution are given, along with altitude and collection season. Representatives of 86 species and morphospecies of the infraorders Dipsocoromorpha, Leptopodomorpha, Gerromorpha and Nepomorpha are listed, distributed in 35 genera and 16 families were found. Based on distributional data, a preference for habitats of stagnant water or slow current and lower altitudes is inferred. Fifteen species are distributed throughout the entire island. A higher species diversity was found in the Eastern sector, with 53 species (61.63%), 16 of which (18.60%) are confined to this area. The strongest biological similarity was found between Eastern and Western sectors (25%), and the weakest between Western and Central sectors (14%).

To obtain critical information on distribution and abundance of Indo-Pacific humpback dolphins (Sousa chinensis) residing in the Pearl River Estuary (PRE), systematic line-transect surveys and photo-identification studies were conducted in the eastern and western sections of the estuary in 2005–2006 and 2007–2008, respectively. Dolphins in the eastern section occurred throughout Lingding Bay, whereas their distribution in the western section extended from the mouth of Modaomen to the channel between Shangchuan and Xiachuan islands. Variations in dolphin distribution during the wet and dry seasons were evident and probably associated with movements of their prey species. Photo-identification of individuals confirmed exchange of at least some individuals between the western and eastern sections of PRE, and thus dolphins from both areas almost certainly comprise a single population. Using line-transect analysis, the total population size of the PRE humpback dolphins was estimated to be 2555 during the wet season and 2517 during the dry season. However, these should be considered preliminary as the coefficients of variation in some survey areas were high. Further studies should focus on refining these estimates and working towards understanding the western boundary of the PRE population.

Rajaji National Park, which forms the north-western limit of the range of the tiger Panthera tigris in India, is bisected into western and eastern sectors by development activities along the banks of the river Ganga. Following a voluntary pastoral Gujjar resettlement programme initiated in the Park by the Uttarakhand Forest Department, we assessed the status of the tiger and its prey. We used sign surveys for tigers, leopards Panthera pardus and their prey, estimated prey densities using line transects and distance sampling, and estimated the density of tigers using photographic capture-recapture analysis. Our results indicate that the use of the area by tigers differed significantly between the two sectors of the Park, with pug mark encounter rates per 250 m segment from sign surveys of 0.07 ± SE 0.04 in the west and 1.6 ± SE 0.3 in the east. Although the high estimated prey densities (> 80 km-2) in the Park have the potential to support high densities of tigers, we photo-captured only one tigress in the western sector and five adult tigers and two cubs in the east (the latter with a mean density of 5.12 ± SE 0.7 per 100 km2). Whereas recovery of the tiger population in the eastern sector following the resettlement of Gujjars is evident, the lack of connectivity to source populations (Corbett Tiger Reserve and eastern Rajaji National Park) and increased anthropogenic pressures appear to have inhibited the recovery of tiger populations in the western sector. Restoration, therefore, of the Chilla-Motichur corridor to facilitate the dispersal of tigers from the eastern to the western sector of the Park is of critical importance.

Palaeoglacial and palaeoenvironmental conditions of the Gangdise Mountains, southern Tibetan Plateau, as revealed by an ice-free cirque morphology analysis