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GRACE (Gravity Recovery and Climate Experiment) has been widely used to evaluate terrestrial water storage (TWS) and groundwater storage (GWS). However, the coarse‐resolution of GRACE data has limited the ability to identify local vulnerabilities in water storage changes associated with climatic and anthropogenic stressors. This study employs high‐resolution (1 km2) GRACE data generated through machine learning (ML) based statistical downscaling to illuminate TWS and GWS dynamics across twenty sub‐regions in the Indus Basin. Monthly TWS and GWS anomalies obtained from a geographically weighted random forest (RFgw) model maintained good consistency with original GRACE data at the 25 km2 grid scale. The downscaled data at 1 km2 resolution illustrate the spatial heterogeneity of TWS and GWS depletion within each sub‐region. Comparison with in‐situ GWS from 2,200 monitoring wells shows that downscaling of GRACE data significantly improves agreement with in‐situ data, evidenced by higher Kling‐Gupta Efficiency (0.50–0.85) and correlation coefficients (0.60–0.95). Hotspots with the highest TWS and GWS decline rate between 2002 and 2023 were Dehli Doab (−442, −585 mm/year), BIST Doab (−367, −556 mm/year), Rajasthan (−242, −381 mm/year), and BARI (−188, −333 mm/year). Based on a general additive model, 47%–83% of the TWS decline was associated with anthropogenic stressors mainly due to increasing trends of crop sown area, water consumption, and human settlements. The decline rate of TWS and GWS anomalies was lower (i.e., −25 to −75 mm/year) in upstream sub‐regions (e.g., Yogo, Gilgit, Khurmong, Kabul) where climatic factors (downward shortwave radiations, air temperature, and sea surface temperature) explained 72%–91% of TWS/GWS changes. The relative influences of climatic and anthropogenic stressors varied across sub‐regions, underscoring the complex interplay of natural‐human activities in the basin. These findings inform place‐based water resource management in the Indus Basin by advancing the understanding of local vulnerabilities. Plain Language Summary: We used GRACE data to understand how water storage has changed over time across the Indus Basin at a resolution of 1 square kilometer. We generated the new high‐resolution data using machine learning techniques that implemented statistical methods. The new data for analyzing water storage matched well with the original data on a larger scale. Additionally, comparing this detailed data with measurements from 2,200 wells showed that our new method works well. The new high‐resolution data help us detect hotspots of water storage decline where water availability may face challenges in the future if status quo continues. Human activities like more farming, using more water, and building more areas for people to live are a major driver of the water storage decline. In upstream areas less influenced by human impacts, the decline is driven more by climatic factors. By improving understanding of local vulnerabilities, our study supports planning interventions for specific regions based on the need to reduce the impact of human activities or adapt to climate change. Key Points: Terrestrial water storage (TWS)/groundwater storage (GWS) derived from downscaled GRACE data show a declining trend across most sub‐regions of the Indus Basin between 2002 and 2023Anthropogenic stressors explain 47%–83% of TWS decline in the majority of sub‐regionsTWS/GWS changes in upstream sub‐regions, where shortwave radiations mainly control the TWS changes, are well explained by climatic factors [ABSTRACT FROM AUTHOR]

Water security and food security in the Indus basin are highly interlinked and subject to severe stresses. Irrigation water demands presently already exceed what the basin can sustainably provide, but per-capita food availability remains limited. Rapid population growth and climate change are projected to further intensify pressure on the interdependencies between water and food security. The agricultural system of the Indus basin must therefore change and adapt to be able to achieve the associated Sustainable Development Goals (SDGs). The development of robust policies to guide such changes requires a thorough understanding of the synergies and trade-offs that different strategies for agricultural development may have for water and food security. In this study, we defined three contrasting trajectories for agricultural system change based on a review of scientific literature on regional agricultural developments and a stakeholder consultation workshop. We assessed the consequences of these trajectories for water and food security with a spatially explicit modeling framework for two scenarios of climatic and socio-economic change over the period 1980–2080. Our results demonstrate that agricultural system changes can ensure per capita food production in the basin remains sufficient under population growth. However, such changes require additional irrigation water resources and may strongly aggravate water stress. Conversely, a shift to sustainable water management can reduce water stress but has the consequence that basin-level food self-sufficiency may not be feasible in future. This suggests that biophysical limits likely exist that prevent agricultural system changes to ensure both sufficient food production and improve water security in the Indus basin under strong population growth. Our study concludes that agricultural system changes are an important adaptation mechanism toward achieving water and food SDGs, but must be developed alongside other strategies that can mitigate its adverse trade-offs. [ABSTRACT FROM AUTHOR]

This study deals with unraveling the diagenesis-induced porosity evolution in a mixed clastic-carbonate sequence of the Middle Permian Indus Basin, Pakistan. Multiple data sets including outcrop, petrography, cathodoluminescence, scanning electron microscopy (SEM), mineralogy, and geochemical isotopic compositions were integrated to establish a link between porosity evolution and diagenesis. The spatial thickness and facies variations of the strata at outcrop scale are inherently controlled by the underlying bathymetry of the basin with deepening westward trend. The low values of δ18O of the target strata, relative to average values of the Permian carbonate, hints to diagenetic alteration in the strata. The data sets used in this study reveal modification of the strata in four environments, that is, i) early marine diagenesis indicated by micritization, pervasive dolomitization and isopachous fibrous cements, followed by ii) meteoric dissolution, and iii) shallow burial diagenetic processes including the precipitation of blocky cement, compaction of skeletal and non-skeletal allochems, and stylolites, and iv) a deep burial environment, characterized by pressure solution, and micro-fractures. The clastic intervals host subangular to subrounded quartz grains, floating textures, and almost complete absence of deleterious clay minerals, consequently resulting in the preservation of primary porosity. The primary porosity of carbonate intervals is preserved in the form of intercrystalline and intracrystalline porosity. The secondary porosity evolved through various diagenetic phases in the form of fractures and dissolution. The diagenetic solution mediated by organic matter in carbonates may have experienced both bacterial decomposition and thermochemical sulfate reduction, precipitating sulfides within the pores. The plug porosity/permeability analyses generally suggest high porosity in the siliciclastic unit, and carbonates with wackestone fabric while lower values were observed for the inner shelf pure carbonate facies. However, both intervals show very low permeability values probably due to isolated moldic pores and intense micritization. Therefore, clastic intervals may provide an opportunity to serve as a moderate reservoir; however, the carbonate intervals possess very low permeability values and could generally be considered as low-moderate reservoir potential.

Soil erosion has resulted in removal of the topsoils containing fine soil particles and plant nutrients, causing decrease in soil fertility in the Hindu Kush, Karakoram and Himalaya (HKH) region. The existing production of cereal crop grains has been reduced to one third of the potential crop grains production owing to land degradation and poor farming practices. It is necessary to assess risk of soil loss and identify appropriate controlling measures to address issues of low agriculture productivity and water insecurity in the region. In the present study, severity of soil loss was predicted using Revised Universal Loss Equation (RUSLE) and ecological measures were identified for sustainable mountain agriculture in the HKH region of Upper Indus Basin, Pakistan. Overall 62.6% area was found to have very low risk of soil loss, i.e., <5 t/(ha·yr), 15.8% area low risk, i.e., 5–25 t/(ha·yr) and 7.5% area moderate risk, i.e., 25–50 t/(ha·yr) in the region. The risk was high, i.e., 50–100 t/(ha·yr) and very high, i.e., >100 t/(ha·yr) in about 6.8% and 7.4% areas respectively. The mean rate of soil loss was about 41.9 t/(ha·yr) in the Hindu Kush, 31.1 t/(ha·yr) in the Himalayas, 18.8 t/(ha·yr) in the Karakoram and overall 29.7 t/(ha·yr) in the three HKH ranges. As such no considerable measures have been adopted by the communities for restoration of the degraded areas except raising fruit/farm trees and supporting limited social forestry for their livelihoods. The slopes cleared for cultivation and susceptible to erosion may be stabilized through sowing/planting of multi-purpose plant species and formation of proper bench terraces. The conservation of forest ecosystem and pastures at higher elevations would help in reducing overland water flow, risk of flash flood hazard and minimizing sediment loads in the downstream. It is essential to adopt site-specific resource conservation techniques and restore possible ecosystem health for sustainable agriculture and economic development in the region in future. [ABSTRACT FROM AUTHOR]

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Many environmental studies have shown that a systems approach, including complete supply chains, is relevant for the assessment of the consequences of production and consumption on natural resources. This can also be applied to water. Although water consumption also includes water supply chains, often irrigation supply chains are excluded in water footprint (WF) studies. Using information from water management studies on water losses, we propose an improved WF method that includes blue crop WFs and WFs of irrigation supply chains indicating total agricultural blue WFs. A systems approach considering not only irrigation technology but whole water supply chains, also distinguishing between surface and groundwater, is needed to improve efficient blue water use in agriculture. This method is applied to the Pakistani part of the Indus basin that includes the largest man-made irrigation network in the world. The total agricultural blue WF is 1.6 times the blue crop WF. Surface water losses vary between 45 and 49%, groundwater losses between 18 and 21% and are smaller than results from water management studies. Differences between provinces and canal commands are large. The identification of hotspots provides a tool to improve water management. Earlier WF studies might have underestimated agricultural water consumption if supply chains are neglected. More water efficient agriculture should take supply chain losses into account probably requiring water management adaptations, which is more a policy than an agriculture task. WFs of supply chains are also relevant for other sectors, like industry or municipal water supply. [ABSTRACT FROM AUTHOR]

Many environmental studies have shown that a systems approach, including complete supply chains, is relevant for the assessment of the consequences of production and consumption on natural resources. This can also be applied to water. Although water consumption also includes water supply chains, often irrigation supply chains are excluded in water footprint (WF) studies. Using information from water management studies on water losses, we propose an improved WF method that includes blue crop WFs and WFs of irrigation supply chains indicating total agricultural blue WFs. A systems approach considering not only irrigation technology but whole water supply chains, also distinguishing between surface and groundwater, is needed to improve efficient blue water use in agriculture. This method is applied to the Pakistani part of the Indus basin that includes the largest man-made irrigation network in the world. The total agricultural blue WF is 1.6 times the blue crop WF. Surface water losses vary between 45 and 49%, groundwater losses between 18 and 21% and are smaller than results from water management studies. Differences between provinces and canal commands are large. The identification of hotspots provides a tool to improve water management. Earlier WF studies might have underestimated agricultural water consumption if supply chains are neglected. More water efficient agriculture should take supply chain losses into account probably requiring water management adaptations, which is more a policy than an agriculture task. WFs of supply chains are also relevant for other sectors, like industry or municipal water supply.

Arsenic (As) in natural hydrological systems is known as a worldwide major environmental concern. A geochemical and sedimentological study was done to ascertain the origin and geographical distribution of As in surface water and fluvial sediment collected from the floodplains/basins of the River Indus and its four major tributaries that drain through the northern Pakistan. The hydrogeochemical compositions of all five rivers were similar with calcium (Ca2+) and bicarbonate (HCO 3 −) being the dominating ions. The concentration of As ranged from 0.62–24.05 μg/L (average 3.7 ± 3.5 μg/L, n = 61) in river water, 2.3–23.4 mg/kg (average 5.7 ± 3.9 mg/kg) in suspended sediment, and 2.0–13 mg/kg (average 4.13 ± 2.3 mg/kg) in fluvial sediment. Various approaches were used, including mineralogical, sequential extraction, geochemical, and statistical analyses to investigate the distribution, behavior, and potential sources of As in the sediment. The effect of geological factors on the distribution of As was also studied. No noticeable changes in the relative abundance of minerals were observed in the sediment at different locations along the river. Both mineralogical and statistical analyses showed that silicate minerals like muscovite, biotite, and chloride are the main As reservoir while oxides minerals like hematite and magnetite, which are minor components in the sediment are second largest As carrier. A geochemical baseline, using the normalization and cumulative frequency distribution curves was constructed for As. The estimated mean human contribution of As was 3.4% in the Indus River, 1.9% in the Jhelum River, 13.7% in the Chenab River, 17.5% in the Ravi River and 5.4% in the Sutlej River, indicating relatively higher effects of anthropogenic activity along the Chenab River and Ravi River. The almost negligible effects of anthropogenic activities were additionally confirmed through the pollution assessment parameters estimated from the geo-enrichment, contamination factors, and accumulation index analyses. The current data suggest that As transported by the Indus River and its major tributaries is accumulated in the sediment and is potentially incorporated in the sedimentary aquifers situated along the Indus Basin and surrounding areas. Based on the current study, it is concluded that the source of As is dominantly geogenic whereas the role of anthropogenic activities is considered negligible except along the Ravi River which showed relatively a higher percentage (17.5%) of human or industrial contribution. [ABSTRACT FROM AUTHOR]

This study demonstrates how an integrated geochemical and petrophysical analysis can be used to evaluate the petroleum generation potential of source and reservoir rocks. The Eocene and Palaeocene sequences of the Potwar Basin, located in the upper Indus Basin of Pakistan, were analyzed. Well logs and Schlumberger log interpretation charts were used for the petrophysical analysis of the Chorgali Formation’s reservoir potential. Geochemical methods were applied to 34 well-cutting Sakesar and Patala formations samples. Results from Vitrinite Reflectance (VR) (%Ro) and Tmax data suggest that both formations have reached the peak of their oil generation window. The Sakesar Formation has a mean TOC of 1.88 wt. % and HI values of 375 mg HC/g TOC. The Patala Formation has a mean TOC of 3.33 wt.% in well A and HI values ranging from 2.4 to 369 mg HC/g TOC in well B, with a mean TOC of 3.52 wt%. Both formations have mixed Type II/III kerogen. The findings indicate that both the Sakesar and Patala formations possess good oil/gas-generation potential and may act as source rocks in the Potwar Basin. Petrophysical analysis of the Chorgali Formation shows an average porosity of 10.32%, water saturation of 36.14%, and hydrocarbon saturation of 63.85%. This indicates that the Chorgali Formation has an average to good reservoir potential. The research findings will aid exploration and production companies in the Fimkassar Oilfield. [ABSTRACT FROM AUTHOR]

Recent advancements in technologies to produce natural gas from shales at economic rates has revealed new horizons for hydrocarbon exploration and development worldwide. The importance of shale oil and gas has aroused worldwide interest after the great success of production in North America. In this study, different marine source rocks of Pakistan are evaluated for their shale gas potential using analogs selected from various North American shales for which data have been published. Pakistani formations reviewed are the Datta (shaly sandstone), Hangu (sandy shale), Patala (sandy shale), Ranikot (shaly sandstone), Sembar (sandy shale) and Lower Goru (shaly sandstone) formations, all of which are known source rocks in the Indus Basin. Available geological data of twenty-six wells (e.g., geological age, depositional environment, lithology and thickness), geochemical data (e.g., total organic carbon (TOC), vitrinite reflectance (Ro), rock pyrolysis analysis and maturity), petrophysical data (e.g., porosity and permeability) and dynamic elastic parameters estimated from logs (Young’s modulus and Poisson’s ratio) have been investigated. According to this study, the Pakistani shales are explicitly correlated with the most active shale gas plays of North America. The burial depths or geological position of the Pakistani shales are generally comparable to or slightly higher than the North American shales based on the available data. The thicknesses of the Pakistani (except for the Sembar shale) and North American shales fall in similar ranges. In terms of mineralogical composition, all of the Pakistani shales except the Ranikot and Hangu shales have quartz contents in the 40% to 50% range (approximately), which is similar to most of the North American shales. The high maximum TOC of the Hangu and Sembar shales (10%) is comparable to the New Albany, Antrim and Duvernay shales. The maximum TOC values for the Ranikot (3%), Lower Goru (1.5%) and Datta (2%) shales are lower than all North American shales. The TOC of Patal Shale (∼5%–10%) is comparable to Fayetteville and Eagle Ford shales. The geological and geochemical parameters of all the Pakistani shales reviewed in this work are promising regarding their shale gas prospects. However, geomechanical data are required before conclusions on these shales’ economic production can be made with confidence.

The Indus Water Treaty allocated the water of the Ravi River to India, and India constructed the Thein Dam on the Ravi River. This study investigates the water availability of the Ravi Riverfront for both pre-dam and post-dam scenarios augmented with pre-flood, flood, and post-flood sub-scenarios. The study also investigates river water availability for low and high magnitudes (Flow Duration Curves) and its linkages with climate change. The modified Mann–Kendall, Sen's slope estimator, and Pearson correlation were used to investigate the river flows. It was found that there is a remarkable decrease in the river water by −36% of annual mean flows as compared to the pre-dam scenario. However, during the flood season, it was −32% at the riverfront upstream (Ravi Syphon Gauge). The reduction in water volume was found as 2.13 Million Acre Feet (MAF) and 1.03 MAF for maximum and mean, respectively, in the Rabi (Winter) season, and 4.07 MAF and 2.76 MAF for max and mean, respectively, in the Kharif (Summer) season. It was also revealed that 180–750 cusecs of water would be available or exceeded for 90% to 99% of the time at Ravi Riverfront during the flood season. The high flows were mainly controlled by temperature in the pre-dam scenario; presently, this water is stored in the Thein Dam reservoir. In contrast, the precipitation role is significant in the post-dam scenario, which means that the flows in the Ravi River are mainly due to base flow contributions and precipitation. This study is the first step in analyzing the river water availability of the Ravi Riverfront, which will ultimately address the associated problems and their solutions to decision-makers. Additionally, implementing an eco-friendly riverfront promotes urban sustainability in developed urban areas, such as Lahore City, and will lead to a comfortable and healthy lifestyle; this will only be possible with water availability in the Ravi Riverfront reach. [ABSTRACT FROM AUTHOR]

Snow and glacier melt runoff supporting agriculture and livelihoods of large number of communities is becoming highly vulnerable to recent changes in climate and cryosphere in the Himalayan region. In the present study, potential for expanding base of glacier-fed irrigation system was assessed through adopting water availability and topographic suitability indexing approach in the Astore basin, of Pakistan. Availability of glacier-melt water was found 2.0 L/sec/hectare (lps/ha) over high topographic suitability area (0–15° slope < 3500 m), 0.8 lps/ha over combined high and medium suitability area (0–30° slope < 3500 m), and 0.9 lps/ha over net culturable land in the basin. These estimates point toward adequate meltwater availability for establishing kuhl system over high and medium topographic suitability areas in the basin. The scenarios of 20%, 40%, and 60% reduction in glaciated area indicated adequate meltwater runoff for crop farming over high topographic suitability, while the water availability was observed low over medium suitability and net culturable areas. A long-term research on changing climate and cryosphere would be important to understand the hydroglacial dynamics and implications for water resource management in this region in future. [ABSTRACT FROM AUTHOR]

Moderate Resolution Imaging Spectroradiometer (MODIS) products were used in this study which covers a period of 2000–2014. Comparison of the SCA derived from MODIS and Landsat NDSI showed a significant correlation, the resultant coefficient of determination (R2) was 0.85. For analyzing the trend in the SCA, the Mann-Kendall test was applied; the results show an increasing non-significant trend in the mean annual SCA with a Sen's slope value of +16.99 (km2/year), and a significant increasing trend in the winter SCA was identified. The annual mean SCA was 8.92 km2 and 564 km2 for elevation ranges of 5001–5694 m and 4001–4500 m respectively. The spatial extent of snow cover was maximum in 70°–78.3° slope class and minimum in 30°–40° slope class. The results highlight the MODIS snow cover products' capability to assess the spatiotemporal dynamics of snow cover in complex mountainous watersheds. [ABSTRACT FROM AUTHOR]

Land Use/Land Cover (LU/LC) change is among the dominant driving factors that directly influence water balance by transforming hydrological responses. Consequently, a thorough comprehension of its impacts is imperative for sustainable water resource planning and development, notably in developing worlds such as Pakistan, where agriculture is a major livelihood. This research intends to assess the continuing changes in LU/LC and evaluate their probable repercussions on the hydrological regime of the Potohar Plateau. The maximum likelihood classification (MLC) algorithm for land use classification of the high-resolution satellite imageries, the Cellular-Automata Markov Chain Model (CA-MCM) for the projection of LU/LC maps, and the Soil and Water Assessment Tool (SWAT) in tandem with SWAT-CUP for hydrological modeling were employed in this research. The high-resolution climatic dataset (10 × 10 km) was used in SWAT. The LU/LC analysis revealed a continual propagation of agricultural and built-up lands at the detriment of forest and barren land during the last three decades, which is anticipated to continue in the future, too. Hydrological model calibrations and validations were performed on multi-basins, and the performance was evaluated using different statistical coefficients, e.g., the coefficient of determination (R2), Nash–Sutcliffe Efficiency (NSE), Kling–Gupta Efficiency (KGE), and Percent Bias (PBIAS). The results yielded that the model performed very well and demonstrated the model's robustness in reproducing the flow regime. The water balance study revealed that the anticipated LU/LC changes are projected to decrease the mean annual surface runoff, water yield, and streamflow due to an increase in percolation, lateral flow, sub-surface flow, and evapotranspiration. More significant variations of the water balance components were observed at the sub-basin level, owing to the heterogeneous spatial distribution of LU/LC, than at the basin level. The outcome of this study will provide pragmatic details to legislative bodies to develop land and water management ameliorative strategies to harness hydrological changes sustainably. [ABSTRACT FROM AUTHOR]

A precise rainfall-runoff prediction is crucial for hydrology and the management of water resources. Rainfall-runoff prediction is a nonlinear method influenced by simulation model inputs. Previously employed methods have some limitations in predicting rainfall-runoff, such as low learning speed, overfitting issues, stopping criteria, and back-propagation issues. Therefore, this study uses distinctive soft computing approaches to overcome these issues for modeling rainfall-runoff for the Mangla watershed in Pakistan. Rainfall-runoff data for 29 years from 1978–2007 is used in the study to estimate runoff. The soft computing approaches used in the study are Tree Boost (TB), decision tree forests (DTFs), and single decision trees (SDTs). Using various combinations of past rainfall datasets, these soft computing techniques are validated and tested for the security of efficient results. The evaluation criteria for the models are some statistical measures consisting of root means square error (RMSE), mean absolute error (MAE), coefficient of determination (R2), and Nash–Sutcliffe efficiency (NSE). The outcomes of these computing techniques were evaluated with the multilayer perceptron (MLP). DTF was found to be a more accurate soft computing approach with the average evaluation parameters R2, NSE, RMSE, and MAE being 0.9, 0.8, 1000, and 7000 cumecs. Regarding R2 and RMSE, there are about 57% and 17% of improvement in the results of DTF compared to other techniques. Flow duration curves (FDCs) were employed and revealed that DTF performed better than other techniques. This assessment revealed that DTF has potential; researchers may consider it an alternative approach for rainfall-runoff estimations in the Mangla watershed. [ABSTRACT FROM AUTHOR]

The Lower to Middle Jurassic sedimentary succession is dominated by siliciclastics with a significant amount of black shales in the Indus Basin, Pakistan. Several outcrop samples have been studied using an integrated approach to interpret the conceptual depositional setting from carbon and oxygen isotopes (δ13C& δ18O), organic geochemistry, and palynofacies with major and trace element analysis. For interpretation of trace element data, various single and elemental ratios have been used in this research to unlock the geological history of the studied strata. Ti/Al is 1.96 for high-potential source rock and 7.82 for non-potential source rock, and Cr (less than 1) indicates low clastic input with low oxygen for stratified and stagnant water. The ratios of V/(V + Cr), V/(V + Ni), V/Mo, V/Ni, (Cu + Mo)/Zn, Mo/Al, isotopic values of δ13C and δ18O and besides the V/Cr elemental ratio, all proxies indicate that there are oxygen-depleted anoxic conditions at high potentials, while in non-potential source rock, these ratios show oxic to sub-oxic settings. In addition to the trace element correlation with total organic carbon, the influx of organic matter is determined by the palynoafacies analysis, which indicates mixed terrestrial and marine organic influx in high-potential source rock and vice versa. Furthermore, the studies of palynofaceis DFPF A-D and SFPF A-B suggest that the depositional setting of black shale occurred in the anoxic proximal to distal shelf. The results suggest that the regional and local occurrence of black shale during the Lower to Middle Jurassic and its geological condition were addressed, and these play an important role in its depositional and paleooceanographic setting in the Eastern Tethys. [ABSTRACT FROM AUTHOR]

The sandstone units of the Early Cretaceous Lower Goru Formation are significant reservoir for gas, oil, and condensates in the Lower Indus Basin of Pakistan. Even though these sandstones are significant reservoir rocks for hydrocarbon exploration, the diagenetic controls on the reservoir properties of the sandstones are poorly documented. For effective exploration, production, and appraisal of a promising reservoir, the diagenesis and reservoir properties must be comprehensively analyzed first. For this study, core samples from depths of more than 3100 m from the KD-01 well within the central division of the basin have been studied. These sandstones were analyzed using petrographic, X-ray diffraction, and scanning electron microscopic analyses to unravel diagenetic impacts on reservoir properties of the sandstone. Medium to coarse-grained and well-sorted sandstone have been identified during petrographic study. The sandstone are categorized as arkose and lithic arkose. Principal diagenetic events which have resulted in changing the primary characters of the sandstones are compaction, cementation, dissolution, and mineral replacement. The observed diagenetic processes can be grouped into early, burial, and late diagenesis. Chlorite is the dominant diagenetic constituent that occurs as rims, coatings, and replacing grains. The early phase of coating of authigenic chlorite has preserved the primary porosity. The recrystallization of chlorite into chamosite has massively reduced the original pore space because of its bridging structure. The current study reveals that diagenetic processes have altered the original rock properties and reservoir characteristics of the Lower Goru sandstone. These preliminary outcomes of this study have great potential to improve the understanding of diagenetic process and their impact on reservoir properties of the Lower Goru sandstone in the Lower Indus Basin and adjoining areas. [ABSTRACT FROM AUTHOR]

Accurate prediction of river discharge is essential for the planning and management of water resources. This study proposes a novel hybrid method named HD-SKA by integrating two decomposition techniques (termed as HD) with support vector regression (SVR), K-nearest neighbor (KNN) and ARIMA models (combined as SKA) respectively. Firstly, the proposed method utilizes local mean decomposition (LMD) to decompose the original river discharge series into sub-series. Next, ensemble empirical mode decomposition (EEMD) is employed to further decompose the LMD-based sub-series into intrinsic mode functions. Further, the EEMD decomposed components are used as inputs in three data-driven models to predict river discharge respectively. The prediction of all components is then aggregated to obtain the results of HD-SVR, HD-KNN and HD-ARIMA models. The final prediction is obtained by taking the average prediction of these models. The proposed method is illustrated using five rivers in Indus Basin System. In five case studies, six models were built to compare the performance of the proposed HD-SKA model. The data analysis results show that the HD-SKA model performs better than all other considered models. The Diebold-Mariano test confirms the superiority of the proposed HD-SKA model over ARIMA, SVR, KNN, EEMD-ARIMA, EEMD-KNN, and EEMD-SVR models. [ABSTRACT FROM AUTHOR]

The Indus Basin is considered as prolific hydrocarbon-bearing province of Pakistan. The study area is located in the Middle Indus Basin. Two wells (Bagh-X-01 and Budhuana-01) were drilled in the vicinity of the study area to determine the hydrocarbon potential of the area. Both wells show no hydrocarbon reserves and are thus abandoned. The present study emphasizes two-dimensional subsurface seismic interpretation and rock physics evaluation to estimate reservoir properties of the Jurassic Samana Suk Formation. Data from nine 2-D seismic lines and two wells have been utilized to evaluate the potential. The time contour maps indicate the existence of subsurface structural features in the study area. With the help of the 3-D geological model, the faults are marked in the Samana Suk Formation and the structure is identified as a monocline. The 3-D geological modeling results also reveal that Samana Suk Formation tends to become thin in the northeast, and thick in the southwest. The petrophysical interpretation was performed to find the hydrocarbon potential of the Formation. The cross plot between P-impedance and VpNs ratio shows that the lithology cannot be differentiated by the logs. Rock physics parameters such as Poisson's ratio, bulk modulus, shear modulus, shear wave velocity, primary wave velocity, Vp/Vs ratio, and density indicate that there are no considerable hydrocarbon reserves in the Samana Suk Formation. [ABSTRACT FROM AUTHOR]

This study evaluates the spatial and temporal performance of the Climate Hazard Group InfraRed Precipitation Satellite (CHIRPS) against Tropical Rainfall Measuring Mission (TRMM) Multi-Satellite Precipitation Analysis (TMPA) 3B42/3B43 v. 7 and Global Precipitation Measurement (GPM)-based Integrated Multi-Satellite Retrievals for GPM (IMERG V06), from 2000 to 2013. Several statistical metrics were used to assess the performance of CHIRPS over the Indus Basin, and its hydrological utility is also assessed using the Soil and Water Assessment Tool (SWAT). The Gilgit and Soan basins were selected for hydrological modelling. The results demonstrate the spatial and temporal dependency of CHIRPS, i.e. better performance was observed in the Lower Indus Basin (LIB) while poor performance was observed in the Upper Indus Basin (UIB). The hydrological assessment of CHIRPS revealed poor performance (overestimation of streamflow) across the Gilgit Basin during both calibration and validation periods. Satisfactory to good performance was obtained across the Soan Basin. [ABSTRACT FROM AUTHOR]

While historically significant for ancient civilizations, the Indus basin is also known for its floods and complex anthropogenic management history. Resulting from years of modifications by the pre-British era Mughal rulers followed by the post-partition division of river waters among the two neighbors, India and Pakistan, Pakistan faces severe management and financial challenges of water management. This study investigates the intricacies arising from this complicated management doctrine for the lower Indus basin. A detailed remote sensing-based analysis of the significant floods to hit the lower Indus basin since 2000 has been provided. Flood years were identified, and Moderate Resolution Imaging Spectroradiometer (MODIS) data for the years 2003, 2005, 2006, 2010, 2011, 2012, 2015, and 2016 were used to map their spatiotemporal extents. Almost all the flood water accumulated in the north is released in one river channel of the lower Indus basin. Further, the challenges were exacerbated due to the excessive rainfall in 2011 and 2012 in southeastern Sindh. A trend analysis of rainfall data shows an increase in the southern basin in the last 21 years, particularly toward the central plains and Sindh Province. The floodwater accumulated in the lower basin for as many as ~ 425 days on average, stretching to ~ 800 days of stagnancy in some places. The water stagnation period has been the highest in the river floodplain, highly populated and cultivated. The analyses of the current study suggest that the riverine channel has been better managed after the 2010 floods; however, the monsoon's shift in 2011 and 2012 led to widespread disaster in low-lying regions of Sindh Province. [ABSTRACT FROM AUTHOR]

A precise rainfall-runoff prediction is crucial for hydrology and the management of water resources. Rainfall-runoff prediction is a nonlinear method influenced by simulation model inputs. Previously employed methods have some limitations in predicting rainfall-runoff, such as low learning speed, overfitting issues, stopping criteria, and back-propagation issues. Therefore, this study uses distinctive soft computing approaches to overcome these issues for modeling rainfall-runoff for the Mangla watershed in Pakistan. Rainfall-runoff data for 29 years from 1978–2007 is used in the study to estimate runoff. The soft computing approaches used in the study are Tree Boost (TB), decision tree forests (DTFs), and single decision trees (SDTs). Using various combinations of past rainfall datasets, these soft computing techniques are validated and tested for the security of efficient results. The evaluation criteria for the models are some statistical measures consisting of root means square error (RMSE), mean absolute error (MAE), coefficient of determination (R2), and Nash–Sutcliffe efficiency (NSE). The outcomes of these computing techniques were evaluated with the multilayer perceptron (MLP). DTF was found to be a more accurate soft computing approach with the average evaluation parameters R2, NSE, RMSE, and MAE being 0.9, 0.8, 1000, and 7000 cumecs. Regarding R2 and RMSE, there are about 57% and 17% of improvement in the results of DTF compared to other techniques. Flow duration curves (FDCs) were employed and revealed that DTF performed better than other techniques. This assessment revealed that DTF has potential; researchers may consider it an alternative approach for rainfall-runoff estimations in the Mangla watershed.

The high‐altitude Indus basin is one of the most complex and inadequately explored mountain terrains in the World, where reliable observations of precipitation are highly lacking. Therefore, spatially distributed precipitation products developed at global/regional scale are often used in several scientific disciplines. However, large uncertainties in precipitation estimates of such precipitation data sets often lead to suboptimal outcomes. In this study, performance of 27 widely used gridded precipitation products belonging to three different categories of gauge‐based, reanalysis and merged products is evaluated with respect to high‐quality reference climatologies of mean monthly precipitation. Widely used statistical measures and quantitative analysis techniques are used to analyse the spatial patterns and quantitative distribution of mean monthly, seasonal and annual precipitation at sub‐regional scale. Mean annual precipitation estimates of the gridded data sets are cross validated with the corresponding adjusted streamflows using Turc‐Budyko non‐dimensional analysis. Results reveal poor to moderately good performance of the gridded data sets. Marked differences in spatiotemporal and quantitative distribution of precipitation are found among the data sets. All data sets are consistent in their patterns showing negative or dry bias in wet areas and positive or wet bias in dry areas, although considerable differences in the magnitudes of the biases are noticed at sub‐regional scale. None of the data sets is equally good for all sub‐regions due to very high spatiotemporal variability in their performance at sub‐regional scale. Gauge‐based and merged products performed better in dry regions and during monsoon season, while reanalysis products provided better estimates in wet areas and during winter months. GPCC V8, ERA5 and MSWEP2.2 are found better than their counter‐grouped data sets. Overall, ERA5 is found most acceptable for all sub‐regions, particularly at higher‐altitudes, in wet areas and during winter months. [ABSTRACT FROM AUTHOR]

The retreating behavior of glaciers observed in most of the Hindu Kush–Karakoram–Himalaya (HKH) region has given rise to the formation and expansion of numerous glacial lakes in the region. The lakes expansion under changing climate usually poses high risk of glacial lake outburst flood (GLOF) hazard for the downstream communities. In the present study, the risk of glacial lake outburst flood was investigated in the HKH region of Pakistan using LANDSAT-8 OLI (Operational Land Imager) image data of 2013 period coupled with ground information. The results of present study revealed 3044 lakes (surface area about 134.8 km2) in the three HKH ranges, maximum in the Karakoram (1325) and minimum in the Hindu Kush range (722) during 2013. The lakes exhibited an overall increase of about 26% in number and 7% in area in the region during 2001–2013 period. The increase in lake number was 91% within 2500–3500 m, 20% within 3500–4500 m and 31% within 4500–5500 m elevation range. Among total identified lakes during 2013, 36 were characterized as potentially dangerous glacial lakes (PDGLs) that can pose GLOF hazard in the HKH region. A regular monitoring of cryosphere changes and critical glacial lakes is essential to develop sustainable risk management strategies for this region in future. [ABSTRACT FROM AUTHOR]

Himalayan region is a fragile zone rich in water resources and biodiversity. The critical balance between the hydrological parameters and the flora and fauna makes it susceptible to larger implications due to the warming rates of climate. This zone comprises about 12 river basins, out of which the Indus forms the most important and extensive river system along with its tributaries and water bodies spreading over several countries. Indus River plays an important role to fulfill the water requirement of agriculture and domestic use in the Himalayan region. The present study was conducted to evaluate the impact of climate change on water resources in the Himalayan region and its sustainability. An in-depth inventory of the basin was discussed in the light of the changing climatic conditions. Research carried out in the Himalayan region on water resources in climate change scenario is reviewed and the effects of climate change on precipitation, river flows, glaciers, and extreme hydrological events have been discussed. The change in climate often leads to higher rates of evapo-transpiration, lesser rainfall, and drying up of the basin. The researchers have clearly indicated adverse changes in the hydrological cycle, water reserves, biodiversity and the quality of human life in the region because of the global warming. The study of the warming trends, decreasing precipitation, increased climate-induced disasters such as floods and Glacier Lake Outburst Floods (GLOFs) will help in minimizing the adverse impact of climate change on hydrology and water resources of the basin by developing strategies to attain sustainable development and management of the whole region. [ABSTRACT FROM AUTHOR]

In this paper, the causes and damages of 2010 flood disaster were analyzed in districts Muzaffar Garh. The study area is one of the severely flood affected districts by floods in the past. A mix research approach is applied to analyse the 2010-flood generating factors and damages in the study area. Primary data were acquired through questionnaires, personal observations and Global Positioning System (GPS). Remote Sensing (RS) Landsat-7 ETM data were obtained from USGS online database for pre- and post-flooding periods to delineate the spatial extent of inundation and estimate different land covers classes with damages. Secondary data regarding Rainfall and river discharge were acquired from concerned Government Departments. Modified Normalized Difference in Water Index (MNDWI) was applied to extract inundation, and supervised image classification algorithm was utilized to classify land cover into different classes. The analysis indicates that the flood was generated by extreme rainfall event in the last week of July, 2010 in the upper catchment areas of River Indus. This generated ever highest discharge in the River Indus. As a consequence, this disastrous flow has breached the left marginal embankment (LME) near Taunsa barrage. Spatially, more than half of the land area was inundated. Moreover, the analysis showed that the inundation incurred total estimated economic loss of about 9.85 million US$. Out of total, the maximum damages of 4.45 million US$ were reported from agriculture sector followed by infrastructures 3.5 million US$. This study will provide an empirical basis for flood disaster management authorities to plan disaster response activity and mitigation strategies to reduce the risk of potential damages. The results can also assist decision makers to evaluate breaching points. [ABSTRACT FROM AUTHOR]

The Indus Waters Treaty (IWT) has now attained the milestone of 60 years (1960– 2020). It was registered by India with the United Nations on 16 January 1962. It has become a global role model of an international legal mechanism for shared transboundary water resources. It has withstood all the strains, conflicts and lows in the bilateral relations between the riparian states of India and Pakistan. The current trends of global climate change in the Anthropocene epoch have exacerbated the risk of conflict over the shared international freshwater resources under the IWT. The receding glaciers, scanty snowfall, changing land system patterns, increasing demands for water to meet irrigation, industrial and domestic water demands, all have cumulatively made an impact on water availability in the Indus Basin. As the climatic changes induce decline in water flows in the Indus Basin rivers, this study seeks to analyze the actual working of the IWT, efficacy of the in-built conflict resolution mechanism and the sheer tenacity to stay course especially on the part of the large upper riparian country, India. It, in turn, has become an exemplar in a treaty-based mechanism as well as in making hydro-diplomacy work for governance of the transboundary water resources in the era of climate change. [ABSTRACT FROM AUTHOR]

The uneven hydro-climatic changes and droughts have significantly affected the socioeconomic condition of people dependent on the Indus basin, Pakistan. This study aims to examine the annual and seasonal hydro-climatic trends for the Upper Indus Basin (UIB), Middle Indus Basin (MIB) and Lower Indus Basin (LIB). The mean monthly data from 44 meteorological and 30 hydrological stations have been analyzed. The Mann Kendall test, Spearman's rho test, linear trend estimation method and Van Belle and Hughes test have been used to perform analysis of hydro-climatic trends. The Standardized Precipitation Index (SPI), Sequential Mann Kendall test and rescaled range analysis have been introduced to detect the seasonal and annual drought. The results showed that significant warming has been observed throughout the Indus basin. The spring precipitation decreased significantly in the UIB with the maximum decrease of 5.3 mm/year. The streamflow of UIB has presented significant increasing trends on annual basis and spring season due to significant warming and glacier melt. The streamflow of MIB presented a significant increase in spring, and it decreased in summer, which can be related to significant warming. The annual precipitation of LIB presented significant increasing trends, and a similar trend has been observed in autumn. However, the LIB showed decreasing streamflow trends on an annual and seasonal basis which is possible due to significant warming trends and water regulation in upstream. The Hurst index value indicates that the Indus basin is expected to maintain current trends and the degree of drought is expected to increase in the future. [ABSTRACT FROM AUTHOR]

Satellite-based Precipitation Estimates (SPEs) have gained importance due to enhanced spatial and temporal resolution, particularly in Indus basin, where raingauge network has fewer observation stations and drainage area is laying in many countries. Formulation of SPEs is based on indirect mechanism, therefore, assessment and correction of associated uncertainties is required. In the present study, disintegration of uncertainties associated with four prominent real time SPEs, IMERG, TMPA, CMORPH and PERSIANN has been conducted at grid level, regional scale, and summarized in terms of regions as well as whole study area basis. The bias has been disintegrated into hit, missed, false biases, and Root Mean Square Error (RMSE) into systematic and random errors. A comparison among gauge- and satellite-based precipitation estimates at annual scale, showed promising result, encouraging use of real time SPEs in the study area. On grid basis, at daily scale, from box plots, the median values of total bias (−0.5 to 0.5 mm) of the used SPEs were also encouraging although some under/over estimations were noted in terms of hit bias (−0.15 to 0.05 mm/day). Relatively higher values of missed (0.3 to 0.5 mm/day) and false (0.5 to 0.7 mm/day) biases were observed. The detected average daily RMSE, systematic errors, and random errors were also comparatively higher. Regional-scale spatial distribution of uncertainties revealed lower values of uncertainties in plain areas, depicting the better performance of satellite-based products in these areas. However, in areas of high altitude (>4000 m), due to complex topography and climatic conditions (orographic precipitation and glaciated peaks) higher values of biases and errors were observed. Topographic barriers and point scale gauge data could also be a cause of poor performance of SPEs in these areas, where precipitation is more on ridges and less in valleys where gauge stations are usually located. Precipitation system's size and intensity can also be a reason of higher biases, because Microwave Imager underestimate precipitation in small systems (<200 km2) and overestimate in large systems (>2000 km2). At present, use of bias correction techniques at daily time scale is compulsory to utilize real time SPEs in estimation of floods in the study area. Inter comparison of satellite products indicated that IMERG gave better results than the others with the lowest values of systematic errors, missed and false biases. [ABSTRACT FROM AUTHOR]

The Palaeocene–Eocene boundary (PEB) interval has been recognized in the Patala Formation, Nammal Gorge Section, Pakistan using lithostratigraphy, stable carbon isotope stratigraphy and integrated biostratigraphy. Four distinct lithological units are identified in the Patala Formation in stratigraphic order from bottom to top; unit‐1 to unit‐4. The top of unit‐3 hosts three closely spaced unconformities demarcated as U1, U2, and U3. The PEB interval is represented by a negative shift of 1.61‰ in δ13CV‐PDB representing the carbon isotopic excursion (CIE) in unit‐2. Based on the encountered foraminifera, dinocysts, and calcareous nannoplanktons, the following biozones are identified across the PEB; two larger benthonic foraminiferal (LBF) zones (SBZ4 and SBZ5), the zonal boundary slightly postdating the CIE, two smaller benthonic foraminiferal zones (BB1 and BB2), three planktonic foraminiferal zones (P4/P5 + E1), four dinocysts zones (Pak‐DV, Pak‐DVI, Pak‐DVII, Pak‐DVIII), and two calcareous nannoplankton subzones (NP9a and NP9b). The following protist, dinocyst and calcareous nannoplanktons encountered in the studied interval advocates for the placement of the possible PEB at the level between samples NAM‐SH‐07 and 08; 1—presence of the smaller benthonic foraminifera Angulogavelinella avnimelechi diagnostic of the base of the CIE and the benthonic extinction event (BEE) Tethys wide, 2—presence of the cosmopolitan and the PEB diagnostic dinocyst species 'Axiodinium augustum', 3—presence of the PEB diagnostic Rhomboaster‐Discoaster calcareous nannoplankton assemblage. The LBF species Alveolina vredenburgi [a marker species of the Larger Foraminiferal Turnover (LFT) associated with the Palaeocene Eocene Thermal Maximum (PETM) and PEB in western Tethys] occurs slightly above the onset of the CIE. Previously reported compositional change in the LBF assemblage from the Salt Range [i.e. the replacement of the Palaeocene orbitoidiform LBF (Setia and Orbitosiphon) by the Eocene LBF (Orthophragminids, Alveolina, Nummulites and Assilina)] also postdates the PEB interval here. The late appearance of Alveolina vredenburgi and the compositional change in the LBF after the onset of the CIE are attributed to the facies variation across the PEB reflecting fluctuating depositional environment due to the active tectonic across this interval. This fluctuation is evident from the smaller benthonic and planktonic foraminiferal dominating assemblages in unit‐2 representing bathyal settings followed by LBF dominating unit‐3 representing shallow carbonate platform settings. The change in LBF assemblage closely resembles the well‐known LFT associated with the PETM as well as the carbonate platform stage III and the PEB reported from other Tethyan sections. [ABSTRACT FROM AUTHOR]

The study of the Indus detritic series in the western part of the Indus basin, between Khalsi and the Zanskar river allows us to distinguish various lithostratigraphic units. New datations have been obtained in several sedimentar y horizons. Marine deposits ceased at the end of early Eocene (Ilerdian —Cuisian) time; detritical series is mainly continental in feature and younger than early Eocene in age. The Indus formations are folded in a large dissymetric north vergent synclinorium of N 120 orientation; numerous folds and reverse faults are observed. The deformation and the epimetamorphism increase southward close to the northward thrusting of the Indus flysch nappes against the Indus detritics. Two main tectonic phases have been observed.

Biased distribution of hydro-climate stations in high elevations are major obstacles for reliable appraisal of the hydro-climatic regime of the Chitral Basin located in the extreme north of Pakistan. We modeled this regime in the ARC-SWAT hydrological model forced with the latest gridded reanalysis ERA5 Land dataset, bias-corrected against a good quality reference dataset. The performance of the gridded dataset was cross-validated by comparing the model flow simulation against the observed flows. The ERA5 Land overall provided reasonably good estimates. The calibrated model on the daily time scale was able to provide excellent values of the employed statistical measures (NSE, KGE, PBIAS, RMSE and MAE). For a future climate change analysis, climate series was devised using two future projection scenarios (RCP4.5 and RCP8.5) using the best performing GCM (MIROC5_rlilp1) out of five investigated GCMs. The results of the climate change analysis reveal increment in the average temperature up to +3.73 °C and +5.62 °C for RCP4.5 and RCP8.5, respectively, while the analysis of precipitation suggests an annual decrease up to −16% and −35% against RCP4.5 and RCP8.5, respectively, by the end of century. A future simulated flow analysis showed an increment of +0.25 % and decrease of −6.82% for RCP4.5 and RCP8.5, respectively. Further analysis of climate suggests seasonal deflections especially in precipitation and flow regimes. A notable climb in flow quantities was observed during spring season (MAM) in spite of the major reduction in precipitation amounts for that season. This implicitly supports a high rate of glacial/snow melt especially in the spring season during that period. Frequent droughts and floods are also projected by examining flow durations at each interval of the 21st century.

Water is vital and an essential entity directly and indirectly for all living creatures from their birth, whereas electrical energy has a dominant role in the growth of society in general and for human beings in particular. Optimal use of water and production of electrical energy at minimum cost are potential research challenges. Hydraulic energy is one of the cheapest and the most exploited renewable energy resource for power generation worldwide, and is in line with the seventh United Nations Sustainable Development Goal (SDG 7). The Indus basin is a trans-boundary basin, and its modeling has been a source of interest for scientists and policymakers. Indus Basin Model Revised (IBMR) has many variants, all focusing on optimal use of water for irrigation purposes. In this paper, the modified IBMR model is proposed addressing both agriculture and power generation aspects simultaneously. This model optimizes the Consumer Producer Surplus (CPS) by considering different water inflow probabilities. A parameter has been introduced in the modified objective function to manipulate the supply of water to agriculture and hydropower generation. The proposed model has been implemented in Generic Algebraic Modeling System (GAMS) and case studies have been investigated in presence and absence of power generation. The results obtained show that, with incorporation of hydropower, basin wide income is increased up to 11.83% using 50% exceedance probability, and results are in agreement with reference power generation estimated by National Transmission and Dispatch Company (NTDC). The SDG 7 targets ensure the reasonable, dependable, sustainable and contemporary energy access to all. The current research is focusing on how Pakistan would achieve the SDG 7 targets. By 2040, it is anticipated that Pakistan’s energy mix will have around 40% of hydropower and 16% of renewable energy.

Abstract The present study details the hydrocarbon source rock geochemistry and organic petrography of the outcrop and subsurface samples of the Middle Jurassic Chiltan Formation and the Lower Cretaceous Sembar Formation from the Sann #1 well Central and Southern Indus Basin, Pakistan. The total organic carbon (TOC), Rock–Eval pyrolysis, vitrinite reflectance (Ro) % and Maceral analysis techniques were used and various geochemical plots were constructed to know the quality of source rock, type of kerogen, level of maturity and migration history of the hydrocarbons. The outcrop and Sann #1 well data on the Sembar Formation reveals poor, fair, good and very good quality of the TOC, type II–III kerogen, immature–mature organic matter and an indigenous hydrocarbon generation potential. The outcrop and Sann #1 well data on the Chiltan Formation show a poor–good quality of TOC, type II–III kerogen, immature–mature source rock quality and having an indigenous hydrocarbon generation potential. The vitrinite reflectance [Ro (%)] values and Maceral types [fluorescent amorphous organic matter, exinite, alginite and inertnite] demonstrate that maturity in both Sembar and the Chiltan formation at surface and subsurface fall in the oil and gas generation zone to cracking of oil to gas condensate zone. Recurrence of organic rich and poor intervals within the Sembar and Chiltan formation are controlled by the Late Jurassic thermal uplift preceding the Indo-Madagascar separation from the Afro-Arabian Plate and Early Cretaceous local transgressive–regressive cycles. From the current study, it is concluded that both Sembar and Chiltan formation can act as a potential hydrocarbon source rock in the study area.

Seismic interpretation delineates the subsurface features (structural and stratigraphic) that are favorable for hydrocarbons' accumulation and Petrophysical analysis evaluates the reservoir characterization in detail. In this paper, 2D seismic data of the Hala area is used to study the structural traps that may be favorable for hydrocarbons. AdamX-01well in the study area is producing. Petrophysical and facies analysis give information about the reservoir parameters. Interpretation incorporates well data. Sands of Lower Goru Formation (Cretaceous) act as a reservoir. Horst and Graben subsurface geological structures are delineated at reservoir levels by using TWT and depth structures maps. Chiltan Limestone Formation (Jurassic) is also marked and contoured in time and depth domains. The petrophysical analysis gives two potential zones with high hydrocarbon saturations. Facies modeling confirms reservoir sands. Integrating the geophysical techniques, possible hydrocarbons, and new potential zones are identified. [ABSTRACT FROM AUTHOR]

• Proportion of high As wells of Ravi floodplain is higher than that of Beas and Sutlej. • As levels in aquifer sands are an order of magnitude higher than the crustal average. • High As intervals in groundwater correspond to intervals of high As in aquifer sands. • Abundant nitrate and sulfate in groundwater suggest oxidation of As-sulfide minerals. • Testing cuttings of aquifer sands for As with field kit can help install safe wells. Recent testing has shown that shallow aquifers of the Ravi River floodplain are more frequently affected by groundwater arsenic (As) contamination than other floodplains of the upper Indus River basin. In this study, we explore the geochemical origin of this contrast by comparing groundwater and aquifer sand composition in the 10–30 m depth range in 11 villages along the Ravi and adjacent Beas and Sutlej rivers. The drilling was preceded by testing wells in the same villages with field kits not only for As but also for nitrate (NO 3 –), iron (Fe), and sulfate (SO 4 2−). Concentrations of NO 3 – were ≥ 20 mg/L in a third of the wells throughout the study area, although conditions were also sufficiently reducing to maintain > 1 mg/L dissolved Fe in half of all the wells. The grey to grey-brown color of sand cuttings quantified with reflectance measurements confirms extensive reduction of Fe oxides in aquifers of the affected villages. Remarkably high levels of leachable As in the sand cuttings determined with the field kit and As concentration up to 40 mg/kg measured by X-ray fluorescence correspond to depth intervals of high As in groundwater. Anion-exchange separation in the field and synchrotron-based X-ray spectroscopy of sand cuttings preserved in glycerol indicate speciation in both groundwater and aquifer sands that is dominated by As(V) in the most enriched depth intervals. These findings and SO 4 2− concentrations ≥ 20 mg/L in three-quarters of the sampled wells suggest that high levels of NO 3 –, presumably from extensive fertilizer application, may have triggered the release of As by oxidizing sulfide-bound As supplied by erosion of black shale and slate in the Himalayas. Radiocarbon dating of sub-surface clay cuttings indicates that multiple episodes of inferred As-sulfide input reached the Ravi floodplain over the past 30 kyr. Why the other river basins apparently did not receive similar inputs of As-sulfide remains unclear. High NO 3 – in groundwater may at the same time limit concentrations of As in groundwater to levels lower than they could have been by oxidizing both Fe(II) and As(III). In this particular setting, a kit can be used to analyze sand cuttings for As while drilling in order to target As-safe depths for installing domestic wells by avoiding intervals with high concentrations of As in aquifer sands with the well screen. [ABSTRACT FROM AUTHOR]

Fluid inclusions and oxygen isotope thermometry were carried out on quartz–calcite veins of the Indus Basin in Indus Suture Zone (ISZ) of northwest Ladakh Himalaya to constrain fluid evolution history of the basin. Three types of veins are identified as fault fill, network, and sigmoidal in the study area. The fault fill veins microstructures of calcite and quartz suggest the deformation temperature of veins between 250 and 400 °C and oxygen isotope thermometry provide the range between 192 and 359 °C. The network type veins microstructures of calcite revel deformation temperature in the range of 170—250 °C, and oxygen isotope thermometry indicate vein temperature range between 144 and 276 °C. Stable isotopic values of sigmoidal, and network type veins suggest the magmatic source of fluid. The fault fill veins display magmatic to the marine fluid signature. Microstructures and isotope data set advocate the formation of veins from the wall rocks by leaching processes. Fluid Inclusion Microthermometric dataset indicates that veins were formed at a maximum depth of 20 km at 700 °C. The CO2 fluids were trapped below 6.2 kbar at 700 °C. CH4 fluid was trapped at a shallower depth, between 4.2 kbar, 650 °C and 2.3 kbar, 381 °C. The primary aqueous fluids were trapped below 3.0 kbar up to 2.3 kbar at 594 to 382 °C and secondary aqueous fluids were trapped between 2.9 and 1.5 kbar at 359 to 197 °C. The P–T path for the entrapment defines an initial isothermal decompression (ITD). ITD is also supported by decrepitated and stretched inclusions texture as well as 'C' shaped or hook-like fluid inclusions morphology, which collectively points towards fast basin uplift. [ABSTRACT FROM AUTHOR]

Inorganic contamination in groundwater has become a major health concern because of its acute and chronic health impacts. To investigate the major hydro-geochemical processes controlling groundwater quality in a part of the Indus river basin, 29 groundwater samples were collected and tested for major ions and potentially harmful elements (PHEs) including Mn, Cu, Cd, Cr, Pb, Fe, and Zn. The cations and PHEs were measured using the atomic absorption spectrophotometer and the anions were analyzed using ion chromatograph. Anthropogenic activities and rock–water interactions are the major factors controlling groundwater quality, along with silicate weathering and evaporation. Ca–HCO3 is the dominant water facies, followed by Na–HCO3 and Na–Cl water facies. Among PHEs, Pb is the most dominant contaminant with 21 samples exceeding WHO guidelines followed by Cr and Fe in 27% and 24% of samples, respectively. Health risk to the population for both dermal and direct ingestion was assessed by calculating chronic dose index (CDI), hazardous quotient (HQ), and hazardous index (HI) for children and adults. HQ through ingestion was highest for Cd because of its low reference dose value. HI for dermal exposure was found to be safe for both children and adults, with values below 1; for ingestion 14 samples had high HI > 1 for adults, and 27 samples for children. High HI values indicate that at a few locations, the groundwater is not suitable for consumption and can cause serious health implications. Proper planning for mitigation is required and large-scale testing along with sharing of wells among neighbors is recommended for reducing exposure. [ABSTRACT FROM AUTHOR]