Integration of Delphi Technique and Analytical Hierarchy Process Method in Assessment the Groundwater Potential Influence Criteria: A Case Study of the Ba River Basin

Water is a boon for all living beings over the world and groundwater is considered one of theindispensable natural sources of potable water. It is necessary to assess and predict the groundwaterpotential to provide insights for decision-makers for proper planning and management of groundwater.The occurrence of groundwater depends on hydrological, ecological, climate, geological, andphysiographical criteria. The purpose of the present study is to choose and attribute scores to all variousfactors that affected groundwater prospects in the Ba river basin. Firstly, the Delphi method was appliedin the expert-based survey to choose six parameters that are considered as influencing factors, namely,lineament density, rainfall, slope, land cover, drainage density, and geology. Then, the weights for thevarious factors were generated using the Analytic Hierarchy Process (AHP) approach which allows thepairwise comparison of criteria influencing the potential areas. The consistency analyses show that thefindings were consistent with a previous study. The consistency and sensitivity analyses showed that theobtained results were coherent, providing the weight vector of the achievable criteria that affect thegroundwater prospect in the study area. The study reveals that lineament density and slope are criteriaaffecting the most prominent groundwater occurrence with 35.1% and 20.1%, respectively. However, theinfluence of other factors (rainfall, land cover, drainage density, and geology) is not visible. These criteriaare assigned to the small weights and do not have a significant influence on the groundwater potential.The study results provide baseline

Study of Hydrothermal Alteration and Mineralization in the Lahbako Field, Jember Regency, East Java Province

Administratively, the research location is in Lahbako Field, Jember Regency, East Java Province. This study discusses the geological characteristics, hydrothermal alteration, and mineralization in the study area. The method used is field data collection by mapping and laboratory analysis in the form of petrographic analysis and mineragraphic analysis. The research area is divided into three geomorphology units, namely a unit with steep hills, a unit with undulating hills, and a unit with sloping plains. The stratigraphy of the study area is divided into five-rock units, while the order of rock units from oldest to youngest is the volcanic Breccia unit, the intercalated Sandstone, and Claystone unit with Tuff insertion, the Diorite Intrusion Unit, the Granodiorite Intrusion Unit, and the youngest unit, namely Alluvium Unit. The research area has a high straightness density value and a straight lineage pattern that tends to be dense. The area with high lineament density is assumed to be the area with the best prospect of alteration and mineralization because the lineament reflects the geological structure which is the path of hydrothermal fluid passage that causes alteration and mineralization. Based on petrographic analysis, the research area has undergone alteration with the type of Philic alteration (Chlorite-Quartz-Feldspar), Prophiliic Alteration (Chlorite-Quartz-Feldspar) Feldspar-Quartz-Epidote) and Argillic Alteration (Alunite-Quartz-Biotite). The study area is indicated as an area with high sulfide epithermal mineral deposits where the indication is based on the discovery of vein textures in the form of Vuggy Quartz and ore minerals in the form of Silver, Copper, and Iron in mineragraphic analysis.

Aeromagnetic and electrical resistivity mapping for groundwater development around Ilesha schist belt, southwestern Nigeria

Aeromagnetic and vertical electrical sounding around Ijano, southwestern Nigeria, was investigated for groundwater potential. Aeromagnetic dataset and vertical electrical sounding were acquired and used to investigate the study area. Oasis Montaj, Microsoft Excel and Arc GIS were used to present the results in maps, images and profiles. In order to map out the geological structures of the study area, magnetic image enhancing filters applied to the total magnetic intensity using Geosoft (Oasis Montaj) are reduction to equator, vertical derivative, total horizontal derivative and upward continuation. These filters helped define the lithological boundaries, geological structures, faults, folds and contacts. The lineament of aeromagnetic map was generated from derived field intensity gradients and solutions of Euler deconvolution carried out on the aeromagnetic data using structural index of 0.5 and 1. The processed image shows the lineaments trends majorly towards NE–SW directions. From these combined results of the study area, consistent aeromagnetic lineament map was generated showing the probable positions and trends of the suspected fractured/faulted zone as well as other basement structures. Hydro-lineament density maps based on lineament were produced from the generalized structure trends in the area. The result from the depth sounding data interpretation indicates three curve types which are H, HA and KH, where curve type H has the highest occurrence. The results from the vertical electrical sounding data revealed that the areas with the highest hydro-lineament density are good for groundwater prospect and development. The study has led to the delineation of areas where groundwater occurrences are most promising for sustainable supply, suggesting that an area with high concentrations of lineament density has a high tendency for groundwater prospecting. The results from the study show that the aeromagnetic technique is capable of extracting lineament trends in an inaccessible tropical forest.

Identification of Groundwater Potential Recharge Zones in Flinders Ranges, South Australia Using Remote Sensing, GIS, and MIF Techniques

In Australia, water resource management is a major environmental, biological, and socio-economic issue, and will be an essential component of future development. The Hawker Area of the central Flinders Ranges, South Australia suffers from a lack of reliable data to help with water resource management and decision making. The present study aimed to delineate and assess groundwater recharge potential (GWRP) zones using an integration between the remote sensing (RS), geographic information system (GIS), and multi-influencing factors (MIF) approaches in the Hawker Area of the Flinders Ranges, South Australia. Many thematic layers such as lithology, drainage density, slope, and lineament density were established in a GIS environment for the purpose of identifying groundwater recharge potential zones. A knowledge base ranking from 1 to 5 was assigned to each individual thematic layer and its categories, depending on each layer’s importance to groundwater recharge potential zones. All of the thematic layers were integrated to create a combined groundwater potential map of the study area using weighting analysis in ArcGIS software. The groundwater potential zones were categorized into three classes, good, moderate, and low. The resulting zones were verified using available water data and showed a relative consistency with the interpretations. The findings of this study indicated that the most effective groundwater potential recharge zones are located where the lineament density is high, the drainage density is low, and the slope is gentle. The least effective areas for groundwater recharge are underlain by shale and siltstone. The results indicated that there were interrelationships between the groundwater recharge potential factors and the general hydrology characteristics scores of the catchment. MIF analysis using GIS mapping techniques proved to be a very useful tool in the evaluation of hydrogeological systems and could enable decision makers to evaluate, better manage, and protect a hydrogeological system using a single platform.

Lineament mapping for a part of the Central Sulaiman Fold–Thrust Belt (SFTB), Pakistan

This study aims to analyze the lineaments using the field data and a remote sensing approach, to describe their relationship with the folds, faults, and regional tectonic stress of the central Sulaiman Fold-Thrust Belt. Joint data, from nine anticlines, has been collected using the scanline method and classified into three sets (JS1, JS2, and JS3) based on their geometrical relationships. Lineaments extracted from the 30 m digital elevation model have been classified subsequently into three lineament sets (LS1, LS2, and LS3) based on the azimuths from the corresponding joint sets. A very high correlation coefficient (rs = 0.97), between the azimuths of the field joints and the remotely sensed lineaments, has been observed which validates that the lineaments are the regional representation of the local field joints. The geometrical relationship of the lineament sets with the fold hinges indicates that the older LS1 and LS2 are strongly related to the regional folding episode, while the younger LS3 is a result of local shears. The chronological interpretation of the deformational events responsible for the lineament sets is constrained by the presence of the Kingri Fault, which induces a strike-slip component within the study area. Furthermore, the controls on the joint and lineament sets, established using multivariate statistics to decipher the effects of lithological and structural contrasts on the lineament density, reveal that an increase in the lineament density can be attributed to the competence and thickness of the rock units as well as the variable local stresses across the different folds. Based on the orientations of these lineament sets, the cumulative direction of the compressive event in the NW-SE direction (310–320) coincides with the regional stress direction of the SFTB.

Contribution of RADARSAT-1 Images to Structural Geological Mapping and Lineament Density Assessment in the Lobo River Watershed at Nibéhibé (Centre-West, Côte d'Ivoire)

The populations living in the Lobo watershed at Nibéhibé are experiencing difficulties in obtaining drinking water. This situation is due to several factors, including a lack of control of the hydrogeological environment. The present study assesses the fracture network that has affected the Precambrian basement aquifer of the Lobo at Nibéhibé catchment area by structural mapping and by studying the spatial distribution of the lineaments. To do this, the study exploits the contribution of radar images. Manually and with the use of adaptive and median filters, 1330 lineaments of varying lengths were derived from the RADARSAT-1 image. The validation approach was based on the comparison of the lineament’s orientations of the current study with those of previous studies, and on the position of the geophysically-implanted boreholes relative to the fractures. This approach showed that the lineaments would most often correspond to fractures and would be involved in the occurrence of groundwater. The analysis of the orientation distribution of the lineaments revealed the heterogeneity of the directions and the predominance of the N-S and E-W family directions. The lineament density map showed that the study area is intensely fractured with a proportion of 93%. The results obtained from this thematic map are useful for the implementation of high efficiency hydraulic drilling programmes and for the implementation of water resources management tools.

Adjustment of Original DRASTIC model by means of Lineament Density to Map Groundwater Vulnerability: Case Study in Rania Basin, Kurdistan Region, Iraq

Groundwater has never been heavily relied on as a water source in Northern Iraq as it has been in the last two decades due to the rapid and often unplanned urbanization, industrial and agricultural projects. This paper attempts to present a concise groundwater vulnerability assessment of Rania basin to the local and regional planning authorities to ensure a more sustainable development in the area. The focus of the study is the Rania basin, which is a part of Dokan sub-basin in North East Iraq. The initial groundwater vulnerability assessment is mapped with standard DRASTIC model. It is then modified by adding “Lineament Density Index” to the original seven DRASTIC parameters due to the previously established close relationship between flow and yield of groundwater with lineament. The area is categorized into five vulnerability index zones of; very low (26%), low (32%), medium (31%), high (11%) and very high (0.012%). The modified model offeres a slightly different vulnerability classification of; very low (16.61%), low (35.45%), medium (30.32), high (17.57) and very high (0.05%). Measured Nitrate concentration is used to validate the assessment results. A progressive increase in nitrate concentration somehow reflects the different vulnerability zones identified by the DRASTIC models in the area. Samples of wet season show 15.96 mg/l, 17.68 mg/l and 20.1 mg/l for very low vulnerability, low vulnerability and medium vulnerability zones when classified by modified DRASTIC model.

AUTOMATIC LINEAMENTS MAPPING AND EXTRACTION IN RELATIONSHIP TO NATURAL HYDROCARBON SEEPAGE IN UGWUEME, SOUTH-EASTERN NIGERIA

The study focus on the integration of Remote Sensing and Geographic Information System for identification and delineation of lineaments in relation to natural hydrocarbon seepage, which occur in Ugwueme, South-Eastern Nigeria. To achieve this objective, remotely sensed data (ASTER Digital Elevation Model and Landsat 8 OLI/TIRS) were used to depict the surface expression of faults, folds and fractures which are expressed in the form of lineaments. The global positioning system (GPS) was also used for ground verification. The geology map of the study area, which is elucidated in the geology of Nigeria was used to show the distribution of rocks and other geologic structures. The delineation of lineament features was done automatically with the PCI Geomatica while the Rock ware was used to generate the Rose diagram for demonstration of the direction of the extracted lineaments. The classification of the lineaments density and the lineaments intersection analysis were categorized as very low, low, moderate, high and very high classes respectively. Areas classified as very high to high lineaments density are potential zone, which act as conduits for hydrocarbon seepage. The result shows that a total lineament frequency of 947 km and a total lineament length of 946 km were delineated from the satellite data. The result further shows that areas with high lineaments density are concentrated in the southwest, south, central and northern part of the study area while areas with low lineament density were found within the eastern part of Ugwueme. The Rose diagram highlight the major trend in the (NE-SW), (N-S) and (NW-SE) directions, and the minor trend in the (W-E) direction. These directional trends depict the directions of lineaments which act as conduits zones for hydrocarbon seepage in the region. The overall findings of the study shows that lineament density, lineament intersection and rose diagrams are concepts applicable in hydrocarbon oil and gas seepages.

Spatial Prediction of Groundwater Potentiality Mapping Using Machine Learning Algorithms

Machine learning techniques offer powerful tools for the assessment and management of groundwater resources. Here, we evaluated the groundwater potential maps (GWPMs) in Md. Bazar Block of Birbhum District, India using four GIS-based machine-learning algorithms (MLA) such as predictive neural network (PNN), decision tree (DT), Naïve Bayes classifier (NBC), and random forest (RF). We used a database of 85 dug wells and one piezometer location identified using extensive field study, and employed 12 influencing factors (elevation, slope, drainage density (DD), topographical wetness index, geomorphology, lineament density, rainfall, geology, pond density, land use/land cover (LULC), geology, and soil texture) for evaluation through GIS. The 85 dug wells and 1 piezometer locations were sub-divided into two classes: 70:30 for training and model validation. The DT, RF, PNN, and NBC MLAs were implemented to analyse the relationship between the dug well locations and groundwater influencing factors to generate GWPMs. The results predict excellent groundwater potential areas (GPA) DT RF of 17.38%, 14.69%, 20.43%, and 13.97% of the study area, respectively. The prediction accuracy of each GWPM was determined using a receiver operating characteristic (ROC) curve. Using the 30% data sets (validation data), accuracies of 80.1%, 78.30%, 75.20%, and 69.2% were obtained for the PNN, RF, DT, and NBC models, respectively. The ROC values show that the four implemented models provide satisfactory and suitable results for GWP mapping in this region. In addition, the well-known mean decrease Gini (MDG) from the RF MLA was implemented to determine the relative importance of the variables for groundwater potentiality assessment. The MDG revealed that drainage density, lineament density, geomorphology, pond density, elevation, and stream junction frequency were the most useful determinants of GWPM. Our approach to delineate the GWPM can aid in the effective planning and management of groundwater resources in this region.