Alluvial Material Research Articles

Analysis of Groundwater Salinity Distribution Based on Electrical Conductivity (EC) and Hydrochemical Approaches to Deep Wells in Sayung Subdistrict, Demak Central Java

In coastal areas, obtaining groundwater is not easy due to the lack of geological support conditions that cause water in the area to have poor quality such as groundwater that becomes salty. The coastal area of Sayung Subdistrict has geomorphological conditions whose surface tends to be flat with elevations 0-5 m higher than sea level and is dominated by alluvial material so that it can cause seawater infiltration to increase. The purpose of this research was to determine the distribution of salinity of groundwater in the coastal area of Sayung Subdistrict and to determine the cause of groundwater becoming salty. The method used in this research is the electrical conductivity (DHL) approach which is then classified based on the level of saltiness of groundwater. And then, well water from the sample points was tested using a hydrochemical test with the parameters used, namely the content of cations (Na, K, Mg, Ca) and anions (Cl, CO3, HCO3, SO4, NO3). This research was conducted at 33 well points spread across Sayung sub-district. The results of this study show that the electrical conductivity value obtained is between the range of 928-7,199 μS/cm which is divided into 3 classifications namely fresh water, fresh-brackish water, and brackish water. The analysis of the Trilinier Piper diagram shows that the saltiness of the groundwater is due to indications of seawater mixing characterized by a chloride (Cl) content that is increasingly greater towards the sea.

Soil Genesis of Alluvial Parent Material in the Qinghai Lake Basin (NE Qinghai–Tibet Plateau) Revealed Using Optically Stimulated Luminescence Dating

Alluvial parent material soil is an important soil type found on the Qinghai–Tibet Plateau (QTP) in China. However, due to the limited age data for alluvial soils, the relationship between alluvial geomorphological processes and soil pedogenic processes remains unclear. In this study, three representative alluvial parent material profiles on the Buha River alluvial plain in the Qinghai Lake Basin, northeast QTP, were analyzed using the optical luminescence (OSL) dating method. Combined with physical and chemical analyses of the soil, we further analyzed the pedogenic process of alluvial soil. The alluvial parent material of the Buha alluvial plain predominately yielded ages between 11.9 and 9.1 ka, indicating that the alluvial soil began to form during the early Holocene. The development of the alluvial soil on the first-order terrace presents characteristics of entisol with multiple burial episodes, mainly between 8.5 and 4.0 ka, responding to the warm and humid middle Holocene and high lake levels.

Proposal of an alluvial dike as a nature-based solution for sustainable water management in coastal areas

Climate change affects several environments, and one of the main problems is the availability and pollution of water resources. As a sustainable strategy, nature-based solutions and rescue of ancestral knowledge are economical and environmentally friendly measures. This study aimed to analyse the design of an alluvial dike by integrating ancestral and engineering knowledge to obtain a surface water reservoir that improves the recharge of the coastal aquifer in the Manglaralto community. This study considers a geological-geotechnical analysis of the study area and presents an environmental analysis of civil work to determine its impact on the surrounding ecosystem systems. The alluvial material dike, green structure, 8 m high, allows the reservoir of approximately 0.06 hm3 of water, which allows the recharge of the coastal aquifer with a field capacity (volumetric content) of 0.1 and conserves its ecosystem. From an environmental perspective, reforestation of the riverbank would reduce annual evapotranspiration, and from an economic perspective, the budget would be reduced considerably (60 % owing to ancestral knowledge and community work). The proposed construction of this second dike relates to the context of Sowing and Harvesting Water (SHW) and nature-based solutions, with community participation leading the processes, with technical accompaniment, to contribute to SDG 2030. This study provides the criterion that the integrality of the green structure offers more significant benefits for the ecosystem and its inhabitants.

Vertical riverbed deformations due to in-stream mining

Comparison of the longitudinal profile of a number of lowland rivers in Russia, revealed their deformation due to a half-century of sediment flux and channel morphology adjustment. This problem remains relevant both in theoretical and practical aspects, especially for rivers where long-term mining of sediments from the stream beds extends from kilometers to tens of kilometers. The removal of a large amount of alluvial material from the sediments transport and changes of the riverbed morphometric characteristics triggered the process of leveling the sediment transport capacity along the river by the scour and resulted in a lowering of the bottom and water surface. The intensity of the incision reached 3–8 centimeters, and its progradation along the river 400–700 meters per year. Retrogressive erosion is pronounced, while progressive one is less pronounced, because partially replaced by mechanical removal of alluvial material. Over the past decades the shape of the longitudinal profiles changed from convex or straight to concave with no signs of recovery, despite the mining has been quite moderate for last 30 years or completed on the explored rivers.

Lithotectonic setting, paleoweathering, maturity, sediment recycling and paleoredox conditions of quaternary alluvium from Mayo Sina (Tchad). A geochemical approach

The alluvial material in the two PITs of the Mayo Sina in the southern part of Chad, were subjected to a geochemical analysis in order to determine the source rock lithological composition, tectonic context, degree of weathering, type of climate at the period of weathering, and cycles of sedimentation and maturity. Plotting source lithology charts with values of La/Sc, Th/Sc, La/Co, and Cr/Th indicated that the sediments originated from a felsic source rock composition. The Enrichment of LREE/HREE and a negative chondrite Eu anomaly confirm the felsic source rock composition. A passive tectonic context for the source rock of the sediments is revealed by binary charts (SiO2 versus K2O/Na2O) in conjunction with innovative discrimination plots (DF 1 and DF 2 (Arc-Rift-Col)M1, DF (A-P)M, and DF (A-P)MT). The exceptional degree of plagioclase removal and weathering is demonstrated by the results of the Plagioclase Index of Alteration (PIX) and Chemical Index of Alteration (CIX). The proportion of SiO2/Al2O3 and the new index of compositional variation (ICVnew), which exclude iron and calcium oxides from the formula, indicate that the sediments are immature to mature. Schematic representations of K2O/Na2O ratio indicate that the sediments have undergone both primary to secondary phases of sedimentation.

Incidence of cumulative degree-days on asphalt mixture aging in regions of Ecuador

The aging of asphalt mixes affects the durability of the pavement. The characteristics of the mixture interact in a complex way with the temperature and service time on site, so the use of the cumulated degree-days (CDD) criterion is possible. The work’s objective is to analyze the aging of the mixtures in the Coastal and Andean regions, through the application of the CDD related to the stiffness modulus at 20 °C in the NAT equipment, obtained from cores sampling in roads built in different years and to make observations regarding existing damages associated with durability. Seven sections were selected from similar mixtures placed between 0 and 14 years ago, made with crushed alluvial materials and AC-20 asphalt from the Esmeraldas refinery. The results show that the aging evaluated through the stiffness modulus presented a greater impact in the Coastal region than in the Andean region due to its higher temperatures, allowing the use of the CDD to unify the behaviors in the two regions into a single relationship. Observations show that the probable range of the progressive evolution of damages, from its beginning to its critical phase, is from 45.000 to 80.000 °C-days.

Assessing the Effects of Alluvial Transport in the Kizilirmak River on Dams with Local, Photogrammetric and Remote Sensing Methods

Naturally transported sand, clay, and gravel-like blocks by rivers cause a decrease in water flow and flow velocity. Additionally, uncontrolled disposal of waste materials into the riverbed increases adverse effects and endangers natural life. Over time, the alluvium generated by natural and external factors in river and creek beds leads to flood risks that pose a significant threat to life and property. These sediments, known as alluvium, accumulate in favorable locations in valleys and form alluvial beds with spread movement to broader areas. In Turkey, interventions in river branches and creek beds, as well as insufficient preventive measures, have kept floods a hot topic. To eliminate these issues, it is crucial for every organization to take comprehensive measures and increase environmental awareness by addressing similar areas in large projections. The Kızılırmak River, originating from the Kızıldag slopes in the İmranlı district of Sivas province and passing through the Çorum province before reaching the Black Sea at Bafra Cape, also harbors alluvial risks and adverse effects. It holds significant importance for energy production with 12 dams and hydroelectric power plants (HES) on the river. Additionally, the Pirinçli Hydroelectric Power Plant, with a transmission structure of 13,756 meters between Dodurga district of Çorum province and Güvercinlik and Kumbaba Villages, plays a vital role in electricity production in the region. The Pirinçli HES is located downstream of the Obruk Dam constructed by the State Hydraulic Works (D.S.I.) on the Kızılırmak River. It is known that a significant portion of the sediment accumulation between Güvercinlik Dam and Kumbaba Dam occurred before the construction of the Obruk Dam. Hence, preventing risks that could lead to environmental adversities is of paramount importance. In this study, a combined fieldwork was conducted using different methods to determine the areas where sediments accumulated and the alluvial material being transported cuts off the flow velocity of the Kızılırmak River and causes accumulations between the Güvercinlik Dam and Kumbaba Dam. For this purpose, terrestrial measurements, photogrammetric and remote sensing methods were combined and evaluated together to ensure the integrity of the obtained data.

Impact of Coastal Reclamation on Seagrass Habitat in Palu Bay, Central Sulawesi, Indonesia

Coastal development by conducting reclamation for various uses, for example port construction and operations, is a growing threat to coastal ecosystems including seagrass meadows. For several decades, reclamation for coastal development in Palu Bay has included port construction or extension of single-purpose privately owned port facilities as well as public shipping ports. In addition, reclamation was carried out to provide land for the construction of hotels, housing, recreational areas and coastal protection. The majority of private port terminals are owned by mining companies exporting rock and aggregate from around Palu Bay. There are many quarries in the mountains along the western coast of Palu Bay, and alluvial materials around several rivers along the eastern shore are also exploited. The purpose of this study was to analyse the impact of reclamation on seagrass habitat in Palu Bay, especially the private ports, which the dominant reclamation purposes conducted in this area. This study found about 66 ports around Palu Bay, the majority privately owned by mining companies operating in Palu City and Donggala Regency. The effects of reclamation include reduced seagrass habitat and decreased water quality.

Sidorovite, PtFe3, A NEW MINERAL FROM THE SNEGOVAYA RIVER PLACER, KORYAK HIGHLANDS, RUSSIA

Abstract Sidorovite, ideally PtFe3, is a new mineral from the Epilchik ultramafic complex and nearby Snegovaya River placer, Koryak Highlands, Russia. It was found in isoferroplatinum grains extracted from a heavy-mineral concentrate obtained from crushed lode chromitites and alluvial material. Sidorovite occurs either as a part of complex grains comprising tetraferroplatinum, native iron, hollingworthite, magnetite, serpentine, and chromite or as part of secondary rims which formed together with tetraferroplatinum after isoferroplatinum. According to the Laue pattern obtained by synchrotron microdiffraction, sidorovite is cubic, crystallizing in space group Pm3¯m and adopting an Au3Cu-type crystal structure. Its unit-cell parameters are a = 3.725(4) Å, V = 51.687(4) Å3, Z = 1. The calculated density is 11.815 g/cm3. The strongest X-ray diffraction lines are [d (Å) (I, %) (hkl)] 2.161 (100) (111), 3.711 (48) (100), 1.871 (36) (200), 1.673 (27) (210). No cleavage was observed and hardness could not be determined owing to the small size of the grains. The empirical formula of sidorovite calculated based on four atoms is: Pt1.04(Fe2.89Cu0.05Ni0.02)Σ2.96. The mineral is posited to form through the incorporation of Fe0 by tetraferroplatinum, which arises through the reduction of Fe via H2-bearing fluids produced through the serpentinization of olivine at T < 450 °C. The name of the new mineral honors the Russian geologist and mineralogist Evgeniy Gennadievich Sidorov (1955–2021).

Anthropogenic influence on groundwater geochemistry in Horn Creek Watershed near the Orphan Mine in Grand Canyon National Park, Arizona, USA

Breccia pipe deposits of the Grand Canyon region contain ore grade copper and uranium. Horn Creek is located near the Orphan Mine mineralized breccia pipe deposit, and groundwater emerging from the bedrock in the headwaters of Horn Creek has the highest uranium concentrations in the region. Uranium decreases an order of magnitude between the groundwater at the top of the watershed and the groundwater emerging from the alluvial material lower in the watershed. Horn Creek water has low sulfur and uranium isotopic ratios which may suggest interaction with sulfide and uranium minerals found in mineralized breccia pipe deposits. Per- and polyfluoroalkyl substances were found in low concentrations in groundwater from the bedrock and may be related to mining process materials or other anthropogenic activities. PHREEQC modelling suggests that water that is elevated in uranium emerging from the bedrock in the upper watershed may mix with other groundwater and atmospheric precipitation infiltrated into the alluvial material in the lower watershed. Tritium is elevated in Horn Creek groundwaters, suggesting a component of modern water, some of which may have interacted with Orphan Mine workings. Additional studies could build on this understanding of chemistry changes in the waters of Horn Creek to provide more direct evidence of the contribution of water moving through the Orphan Mine. Supplementary material: Chemical data for this paper are available at https://doi.org/10.5066/F7P55KJN , PHREEQC geochemical simulations are available at https://doi.org/10.5066/P9X17FKG and groundwater chemistry from south of Grand Canyon, AZ is available at https://doi.org/10.6084/m9.figshare.c.6747638 Thematic collection: This article is part of the Geochemical processes related to mined, milled, or natural metal deposits collection available at: https://www.lyellcollection.org/topic/collections/geochemical-processes-related-to-mined-milled-or-natural-metal-deposits

Macroseismic Study of 4th January 2016, Manipur Earthquake, and its Implications

Abstract An earthquake of magnitude 6.7 M (Latitude 24.834N; Longitude 93.656E) on the Richter scale rocked in the Noney area, Tamenglong district, Manipur on 4th January 2016. The shock was strongly felt in most parts of the Northeastern states of India viz. Manipur, Nagaland, Meghalaya, Assam, and its neighboring countries Myanmar and Bangladesh. Macroseismic study was conducted to assess the intensity of ground motion and related damages caused by the earthquake. The damage incidences were mainly reported in structures constructed over the alluvial fill material. Deformations and development of ground fissures were observed in the epicentral tracts of Manipur and liquefaction phenomenon was observed in the Silchar area Assam. The study revealed that higher damage was confined to the area around Noney, Kabuikhullen, Nungba, Leimakhong, and Imphal valley areas in Manipur and Silchar town areas in Assam. Based on field observation, the degree of damage to building structures, and data gathered from the local population using the standard questionnaire, different intensity values were assigned to each locality. Isoseismal map was prepared by drawing the boundaries between different intensity areas at MSK-64 scale. The result indicates that the intensity was within the range of IV to VII. The maximum intensity was found VII in parts of Imphal, Tamenglong, and Silchar and very close to the epicentral tract area of Noney; and lowest intensity IV was observed in other parts of the northeastern states around Dimapur and Kohima in Nagaland state. The location of the epicenter of main shock (M 6.7) was at the intersection of the two major lineaments trending to ENE-WSW and NW-SE. The trend and shape of isoseismals drawn on seismotectonic/geological maps are elliptical along ENE-WSW direction and are found more closely spaced in the north and southern parts of the affected area. The elliptical nature of the isoseismals indicates that this seismic event was caused by movement along a linear surface. Furthermore, the orientation of elliptical isoseismals with a major axis trend in an ENE-WSW direction is almost parallel to the ENE-WSW trend of major lineament/fault in the area. As a result, the ENE-WSW lineament/fault trend appears to be the causative fault for this quake. In addition, one of the nodal plane (NP2) striking 83°, with dip 81° and slip (rake) 38° obtained from fault plane solution USGS shows a similar trend to the direction of generated elliptical isoseismals pattern confirming the event ocurred along a major tectonic lineament in a strike-slip mechanism.

Anthropogenic Contamination in the Free Aquifer of the San Luis Potosí Valley.

The San Luis Potosí valley is an endorheic basin that contains three aquifers: a shallow unconfined aquifer of alluvial material and two deep aquifers, free and confined. The groundwater contamination documented for the shallow aquifer generates contamination of the deep unconfined type aquifer, from which part of the population's drinking water needs are met. This study records incipient anthropogenic contamination of two types: biogenic and potentially toxic trace elements. The studied contaminants include fecal coliform bacteria, total coliform, nitrate, and potentially toxic elements such as: manganese (Mn), mercury (Hg), arsenic (As), and cadmium (Cd). This contamination in some locations exceeds the permissible limit for human consumption. Some major consequences to health, including severe illness, may be caused by the trace elements. The present results give a first signal about the contamination of the deep unconfined type aquifer due to anthropogenic activity in the valley. This is a priority issue because this aquifer supplies drinking water, and in the short or medium term it will have an effect on public health.

Digital soil mapping of lithium in Australia

Abstract. With a higher demand for lithium (Li), a better understanding of its concentration and spatial distribution is important to delineate potential anomalous areas. This study uses a digital soil mapping framework to combine data from recent geochemical surveys and environmental covariates that affect soil formation to predict and map aqua-regia-extractable Li content across the 7.6×106 km2 area of Australia. Catchment outlet sediment samples (i.e. soils formed on alluvial parent material) were collected by the National Geochemical Survey of Australia at 1315 sites, with both top (0–10 cm depth) and bottom (on average ∼60–80 cm depth) catchment outlet sediments sampled. We developed 50 bootstrap models using a cubist regression tree algorithm for each depth. The spatial prediction models were validated on an independent Northern Australia Geochemical Survey dataset, showing a good prediction with a root mean square error of 3.32 mg kg−1 (which is 44.2 % of the interquartile range) for the top depth. The model for the bottom depth has yet to be validated. The variables of importance for the models indicated that the first three Landsat 30+ Barest Earth bands (red, green, blue) and gamma radiometric dose have a strong impact on the development of regression-based Li prediction. The bootstrapped models were then used to generate digital soil Li prediction maps for both depths, which could identify and delineate areas with anomalously high Li concentrations in the regolith. The predicted maps show high Li concentration around existing mines and other potentially anomalous Li areas that have yet to be verified. The same mapping principles can potentially be applied to other elements. The Li geochemical data for calibration and validation are available from de Caritat and Cooper (2011b; https://doi.org/10.11636/Record.2011.020) and Main et al. (2019; https://doi.org/10.11636/Record.2019.002), respectively. The covariate data used for this study were sourced from the Terrestrial Ecosystem Research Network (TERN) infrastructure, which is enabled by the Australian Government's National Collaborative Research Infrastructure Strategy (NCRIS; https://esoil.io/TERNLandscapes/Public/Products/TERN/Covariates/Mosaics/90m/, last access: 6 December 2022; TERN, 2019). The final predictive map is available at https://doi.org/10.5281/zenodo.7895482 (Ng et al., 2023).

Geochemical Characteristics of Cd in Different Parent Soils in Karst Area and Prediction of Cd Content in Maize

The naturally high background value region of Cd derived from the weathering of carbonate has received wide attention. Due to the significant difference in soil physicochemical properties, soil Cd content, and bioavailability of different parent materials in the karst area, there are certain limitations in using the total soil Cd content to classify the environmental quality of cultivated land. In this study, surface soil and maize samples of eluvium and alluvial parent material in typical karst areas were collected systematically; the contents of maize Cd, soil Cd, pH, and oxides were analyzed, the Cd geochemical characteristics of different parent soils and the influencing factors of their bioavailability were revealed, and scientific and effective arable land use zoning suggestions based on the prediction model were suggested. The results showed that the physicochemical properties of different parent material soils in the karst area were obviously different. The alluvial parent material soil had low Cd content but high bioavailability, and the maize Cd exceeding rate was high. The maize Cd bioaccumulation factor was significantly negatively correlated with soil CaO, pH, Mn, and TC, and the correlation coefficients were -0.385, -0.620, -0.484, and -0.384, respectively. Compared with the multiple linear regression prediction model, using the random forest model to predict the maize Cd enrichment coefficient had higher accuracy and precision. Furthermore, a new scheme for the safe utilization of cultivated land at the plot scale based on soil Cd and predicted crop Cd content was proposed in this study, making full use of arable land resources to ensure crop safety.

Simulation of groundwater resource quantity and quality and assessment of the effects of alluvial material dissolution on the changes of qualitative parameters of the Zanjan Plain, Iran

Simulation of groundwater resource quantity and quality and assessment of the effects of alluvial material dissolution on the changes of qualitative parameters of the Zanjan Plain, Iran

Potency of Alluvial Mineral of Luk Ulo River with XRD and AAS in Kebakalan Village Kebumen

Based on petrographic data, XRD, and fluid inclusions, it was interpreted that the quartz veins associated with low sulfide in Karangsambung area underwent 2 stages of system change from mesothermal system to epithermal system. This means showing the mineral potential contained in material, including on the Luk Ulo River where alluvial deposits are present. Therefore, what needs to be done next is to determine the composition of the material of the alluvial material in the Luk Ulo River, Kebakalan Village using XRD, and AAS so that its potential is known. This research is limited to mineral potential in XRD and AAS (Au, Ag, and Cu) in 2 samples, A (sand) and B (rock). XRD results on samples A and B showed that quartz (SiO 2 ) had the highest percentage (30-50%) compared to other minerals. While the results of the AAS tests showed that the highest Au and Ag contents were in sample B and Cu in sample A with total of 19.30 g/ton Au, 8.67 g/ton Ag, and 62.88 g/ton Cu. Meanwhile, the lowest total Au and Ag were in sample A and Cu was in sample B which amounted to Au 11.32 g/ton, Ag 8.67 g/ton, and Cu 34.86 g/ton.

Environmental Impact Assessment of the quarries on Grou River: Khenifra region- Morocco

Khenifra region is rich in geological resources, which attracted a lot of investment, especially the quarrying. The Grou River watershed contains a lot of quarries of alluvial material extraction which causes negative impacts on its environment such as landscape modification, water quality degradation, dust emission and, soil erosion. The evaluation of water quality by measuring physicochemical parameters showed a deterioration of its quality in the downstream area compared to the upstream area. To respond to this situation, we suggest a set of mitigation measure and propose the respect of monitoring and surveillance plans.

Source areas of the Eastern Ebro Valley loess (NE Iberian Peninsula): Heavy mineral composition as a provenance indicator

AbstractLoess deposits of the Eastern Ebro Valley (NE Iberian Peninsula) occupy an area of ~2000 km2 mostly on the east of the Ebro depression and locally in the Móra Basin. We studied 38 samples of loess and 47 samples of their possible source areas, in order to determine the location of the origin of the loess materials, based on their particle size distribution and composition of heavy minerals. Our results clearly differentiate two depositional loess basins disconnected by the reliefs of the Pre‐Coastal Range with different mineralogical signatures: the Ebro Basin and the Móra Basin. The most relevant variables to discern source areas were the percentage of heavy minerals, the concentrations of zircon, staurolite, rutile and inosilicates, and the presence of gypsum. In the Ebro Basin, the largest set of loess deposits is located around a depocenter in the Batea region and along several lateral areas, with materials that come from the central alluvial plain of the Middle Ebro River (25 to >100 km travel distance), in addition to deflated materials from Miocene interfluvial substrates. On the other hand, loess deposits of the Móra Basin come from more proximal source areas (<15 km), originating from the alluvial materials of the Lower Ebro River that contain the contributions of its tributaries, the Cinca and Segre rivers. Taking into account the homogeneity in the mineralogical composition of complex loess sequences, we deduced a general WNW–ESE wind direction, which would have remained constant over the last two cold periods (MIS‐2 and MIS‐6). Along this axis, the Pàndols–Cavalls Range, with a height difference of 200–350 m, acted as a wind barrier separating the loess of Ebro Basin from the loess of Móra Basin.

Improvement of Onsite Wastewater Systems Performance: Experimental and Numerical Investigation

Population growth and the associated increase in the use of Onsite Wastewater Treatment Systems (OWTS) in the Black Hills have been a reason for interest in nitrate contamination within the public water supply over the past few years. The main concern for the Black Hills is the presence of karst formation that all OWTS for wastewater travel faster, limiting the natural attenuation of wastewater contaminants. The treatment performance of common soils in the Black Hills and wood-based media was evaluated using soil column experiments and a numerical model, HYDRUS 2D. Nitrate treatment performances were evaluated using alluvial and cedar soils collected from the Black Hills, sand, woodchips (loose and dense), and biochar. This research investigated hydraulic and reaction parameters through a combination of experimental and inverse modeling approaches. A good agreement was obtained between the measured and model-predicted soil moisture content, with R2 values ranging from 0.57 to 0.99. The model was calibrated using flow data and nitrate concentration data measured from leachate collected at the bottom of the experimental columns. Nitrate removal rates varied from 32.3% to 70%, with the highest removal rate in loose woodchips, followed by dense woodchip and biochar, and the lowest removal rate in alluvial materials. The biochar and loose woodchips removed an additional 20% compared to common soils, attributable to the enhanced denitrification rate due to higher water content and organic content. The use of woodchips and biochar should be implemented in OWTS, where there are known karst formations.

Penentuan Tipe Akuifer Daerah Bulontala Kabupaten Bone Bolango Menggunakan Metode Geolistrik

Research area Geographically, the location is at 0ᵒ31'0''N - 0ᵒ31'30'' North Latitude 123ᵒ8'0'' - 123ᵒ8'30'' East Longitude with an area of ± 22.02 km. The research location is an andesite lava hill unit. because the type of rock found at that location is andesite igneous rock. The purpose of this study is to determine the type or type of aquifer. The method used is in the form of collecting surface and subsurface geological data. The method used is the geoelectric method with the Schlumberger configuration. The results of the research for geological mapping of the research location have morphology in the form of volcanic plains and hills with an altitude of 200 meters above sea level. The statigraphic sequence at the research site is sorted from easy to leader, old unit in the form of Andesite and easy unit in the form of alluvial. As for the geological structure that plays a role in the study, the dominant direction is from the north to the south.Groundwater at the research site follows the topography of the research location which flows from south to north where the water flows from upstream to downstream, from high to low elevation points. based on the results of geoelectric research and well water data collection that the aquifer at that location is shallow with alluvial material types, sand and andesite igneous rocks.The type of aquifer at the research site obtained from geoelectric research is a free aquifer type (not compressed) and only has 1 boundary layer, namely andesite igneous rock.