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Gulraiz Akhter ([email protected]) is Professor at Quaid-i-Azam University (QAU), Islamabad. He has also served as Chairman of Department of Earth Sciences, QAU. He holds a Masters in Geophysics (1984) and a Ph.D. in Hydrogeology from Quaid-i-Azam University, Pakistan. His areas of interest are exploration geophysics, water well design and water quality analysis, numerical groundwater modeling remote sensing, and GIS. He is the author of more than 60 refereed international papers on Geophysics and Hydrogeology. He is a reviewer of many peer reviewed journals. He is an active member of several international and national institutions and scientific committees.
The dynamic nature and unsustainable exploitation of groundwater aquifers pose a range of management challenges. The accurate basin-wide hydrological assessment is very critical for the quantification of abstraction rates, spatial patterns of groundwater usage, recharge and discharge processes, and identification of critical areas having groundwater mining. This study provides the appraisal of remote sensing technology in comparison with traditionally prevailing tools and methodologies and introduces the practical use of remote sensing technology to bridge the data gaps. It demonstrates the example of Gravity Recovery and Climate Experiment (GRACE) satellite inferred Total Water Storage (TWS) information to quantify the behavior of the Upper Indus Plain Aquifer. The spatio-temporal changes in aquifer usage are investigated particularly for irrigation and anthropogenic purposes in general. The GRACE satellite is effective in capturing the water balance components. The basin-wide monthly scale groundwater storage monitoring is a big opportunity for groundwater managers and policymakers. The remote sensing integrated algorithms are useful tools to provide timely and valuable information on aquifer behavior. Such tools are potentially helpful to support the implementation of groundwater management strategies, especially in the developing world where data scarcity is a major challenge. Groundwater resources have not grown to meet the growing demands of the population, consequently, overexploitation of groundwater resources has occurred in these decades, leading to groundwater decline. However, future developments in the field of space technology are envisioned to overcome the currently faced spatio-temporal challenges.
Gulraiz Akhter; Yonggang Ge; Naveed Iqbal; Yanjun Shang; Muhammad Hasan. Appraisal of Remote Sensing Technology for Groundwater Re-source Management Perspective in Indus Basin. Sustainability 2021, 13, 9686 .
AMA StyleGulraiz Akhter, Yonggang Ge, Naveed Iqbal, Yanjun Shang, Muhammad Hasan. Appraisal of Remote Sensing Technology for Groundwater Re-source Management Perspective in Indus Basin. Sustainability. 2021; 13 (17):9686.
Chicago/Turabian StyleGulraiz Akhter; Yonggang Ge; Naveed Iqbal; Yanjun Shang; Muhammad Hasan. 2021. "Appraisal of Remote Sensing Technology for Groundwater Re-source Management Perspective in Indus Basin." Sustainability 13, no. 17: 9686.
The Mirpur area of Pakistan was severely damaged by extensive coseismic liquefaction following an earthquake of Mw 5.8 on 24 September 2019. Villages within 6 km of the epicenter were adversely affected due to extensive coseismic liquefaction-induced surface and shallow subsurface deformations. The earthquake affected all types of buildings and key infrastructure (e.g., the Upper Jhelum Canal and the main Jhelum–Jatlan road). Field observations and associated effects are presented, including horizontal-to-vertical spectral ratio (HVSR) data sets acquired from three sites to evaluate the site response characteristics of the liquefaction-affected soil profiles. As a result, rupture events strongly influenced spectral features (amplitude and frequency) and site-specific 1D shear-wave velocity profiles at sites S1 and S2. The dynamic behavior of HVSRs across ruptures at sites S1 and S2 corresponds to varied levels of seismic amplification, demonstrating the impact of liquefaction-induced ruptures of seismic origin on the site response that have not been reported previously in the literature. The consistent HVSR pattern of well-established high-frequency peaks at site S3 adjacent to partially damaged to completely collapsed buildings of different types further indicates the susceptibility of potential liquefaction hazard. These results agree with the surface liquefaction signatures in the field, revealed by inverted electrical resistivity tomography models in terms of liquified sand plugs, clay lenses and associated fractures, and increasing trends of radon concentration in the soil with decrease in the distance toward ruptures. Additionally, the successful application of HVSR as a cost-effective and speedy tool attests to the potential of the proposed approach in furnishing complementary information for better assessment of liquefaction hazards in the developing world, where financial constraints are a major issue. This can help with seismic hazard analysis and mitigation in the Mirpur area and may have applications in other seismically active regions of the world.
Muhammad Younis Khan; Syed Ali Turab; Liaqat Ali; Muhammad Tahir Shah; S. M. Talha Qadri; Khalid Latif; Ali Ismet Kanli; Muhammad Gulraiz Akhter. The dynamic response of coseismic liquefaction-induced ruptures associated with the 2019 Mw 5.8 Mirpur, Pakistan, earthquake using HVSR measurements. The Leading Edge 2021, 40, 590 -600.
AMA StyleMuhammad Younis Khan, Syed Ali Turab, Liaqat Ali, Muhammad Tahir Shah, S. M. Talha Qadri, Khalid Latif, Ali Ismet Kanli, Muhammad Gulraiz Akhter. The dynamic response of coseismic liquefaction-induced ruptures associated with the 2019 Mw 5.8 Mirpur, Pakistan, earthquake using HVSR measurements. The Leading Edge. 2021; 40 (8):590-600.
Chicago/Turabian StyleMuhammad Younis Khan; Syed Ali Turab; Liaqat Ali; Muhammad Tahir Shah; S. M. Talha Qadri; Khalid Latif; Ali Ismet Kanli; Muhammad Gulraiz Akhter. 2021. "The dynamic response of coseismic liquefaction-induced ruptures associated with the 2019 Mw 5.8 Mirpur, Pakistan, earthquake using HVSR measurements." The Leading Edge 40, no. 8: 590-600.
Seawater intrusion is a major challenge in many coastal areas all around the world, mainly caused by over-exploitation of freshwater resources, climate change, and sea-level rise. Consequently, seawater intrusion reaches several kilometers inland, thus making the freshwater resources polluted and unsuitable for human use. Conventionally, the fresh-saline water interface is delineated by the number of laboratory tests obtained from boreholes. However, such tests suffer from efficiency in terms of data coverage, time, and cost. Hence, this work introduces Dar-Zarrouk (D-Z) parameters, namely transverse resistance (Tr), longitudinal conductance (Sc), and longitudinal resistivity (ρL) computed from non-invasive vertical electrical sounding (VES). Two-dimensional (2D) imaging of D-Z parameters provides a clear distinction of fresh-saline aquifers. Such techniques remove ambiguities in the resistivity interpretation caused by overlapping of fresh and saline aquifers during the process of suppression and equivalence. This study was carried out by 45 VES along five profiles in the coastal area of Bela Plain, Pakistan. D-Z parameters delineate fresh, brackish, and saline aquifers with a wide range of values such as freshwater with Tr > 2000 Ωm2, Sc < 3 mho, and ρL > 20 Ωm; saline water with Tr < 1000 Ωm2, Sc > 25 mho, and ρL < 5 Ωm; and brackish water with Tr between 1000–2000 Ωm2, Sc from 3 to 25 mho, and ρL between 5–20 Ωm. The D-Z results were validated by the physicochemical analysis using 13 water samples and local hydrogeological setting. The obtained results propose that D-Z parameters can be used as a powerful tool to demarcate the fresh-saline aquifer interface with more confidence than other traditional techniques. This geophysical approach can reduce the expensive number of borehole tests, and hence contributes to the future planning and development of freshwater resources in the coastal areas.
Muhammad Hasan; Yanjun Shang; Weijun Jin; Peng Shao; Xuetao Yi; Gulraiz Akhter. Geophysical Assessment of Seawater Intrusion into Coastal Aquifers of Bela Plain, Pakistan. Water 2020, 12, 3408 .
AMA StyleMuhammad Hasan, Yanjun Shang, Weijun Jin, Peng Shao, Xuetao Yi, Gulraiz Akhter. Geophysical Assessment of Seawater Intrusion into Coastal Aquifers of Bela Plain, Pakistan. Water. 2020; 12 (12):3408.
Chicago/Turabian StyleMuhammad Hasan; Yanjun Shang; Weijun Jin; Peng Shao; Xuetao Yi; Gulraiz Akhter. 2020. "Geophysical Assessment of Seawater Intrusion into Coastal Aquifers of Bela Plain, Pakistan." Water 12, no. 12: 3408.
Muhammad Rizwan Mughal; Gulraiz Akhter. Sandstone reservoir modeling based on rock physics characterization for hydrocarbon resource potential in Southern Pakistan. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 2020, 1 -13.
AMA StyleMuhammad Rizwan Mughal, Gulraiz Akhter. Sandstone reservoir modeling based on rock physics characterization for hydrocarbon resource potential in Southern Pakistan. Energy Sources, Part A: Recovery, Utilization, and Environmental Effects. 2020; ():1-13.
Chicago/Turabian StyleMuhammad Rizwan Mughal; Gulraiz Akhter. 2020. "Sandstone reservoir modeling based on rock physics characterization for hydrocarbon resource potential in Southern Pakistan." Energy Sources, Part A: Recovery, Utilization, and Environmental Effects , no. : 1-13.
Muhammad Hasan; Yanjun Shang; Weijun Jin; Gulraiz Akhter. Geophysical investigation of a weathered terrain for groundwater exploitation: a case study from Huidong County, China. Exploration Geophysics 2020, 52, 273 -293.
AMA StyleMuhammad Hasan, Yanjun Shang, Weijun Jin, Gulraiz Akhter. Geophysical investigation of a weathered terrain for groundwater exploitation: a case study from Huidong County, China. Exploration Geophysics. 2020; 52 (3):273-293.
Chicago/Turabian StyleMuhammad Hasan; Yanjun Shang; Weijun Jin; Gulraiz Akhter. 2020. "Geophysical investigation of a weathered terrain for groundwater exploitation: a case study from Huidong County, China." Exploration Geophysics 52, no. 3: 273-293.
Estimation of hydraulic parameters is important for the prediction of the future availability of groundwater reserves. Conventionally, pumping tests are conducted on boreholes to measure these parameters. However, such tests are costly and time consuming, and can only provide limited spatial information. An integrated approach of geophysical method and pumping tests is cost-effective and efficient alternative for the estimation of aquifer parameters. A geophysical method of vertical electrical sounding (VES) was carried out in Huizhou ADS site of China for the delineation of aquifer potential zones to assess the groundwater resources contained within the weathered rock. Initially, the pumping test data were used to determine the hydraulic parameters namely hydraulic conductivity (Kw) and transmissivity (Tw) for available production wells. Afterwards, one empirical relation between pumped hydraulic conductivity (Kw) and aquifer resistivity (ρa), and another between pumped transmissivity (Tw) and transverse resistance (Tr) were obtained to estimate hydraulic conductivity (K) and transmissivity (T) for all VES stations where pumping tests were not conducted. In this way, the entire study area was investigated to delineate the aquifer potential zones i.e., high potential aquifer zone with ρa < 100 Ωm, T > 150 m2/day and K > 4 m/day, medium potential aquifer zone with ρa ranging from 100 to 150 Ωm, T from 100 to 150 m2/day and K from 3 to 4 m/day, poor potential aquifer zone with ρa from 150 to 300 Ωm, T from 50 to 100 m2/day and K from 2 to 3 m/day, and negligible potential aquifer zone with ρa > 300 Ωm, T < 50 m2/day and K < 2 m/day. This investigation also deciphers functional analogous relation of Ωa with K and Tr with T in Huizhou, China. Therefore, similar integrated approach can be used in any geological similar area where the aquifer properties are required for the management of groundwater reserves.
Muhammad Hasan; Yanjun Shang; Weijun Jin; Gulraiz Akhter. Estimation of hydraulic parameters in a hard rock aquifer using integrated surface geoelectrical method and pumping test data in southeast Guangdong, China. Geosciences Journal 2020, 25, 223 -242.
AMA StyleMuhammad Hasan, Yanjun Shang, Weijun Jin, Gulraiz Akhter. Estimation of hydraulic parameters in a hard rock aquifer using integrated surface geoelectrical method and pumping test data in southeast Guangdong, China. Geosciences Journal. 2020; 25 (2):223-242.
Chicago/Turabian StyleMuhammad Hasan; Yanjun Shang; Weijun Jin; Gulraiz Akhter. 2020. "Estimation of hydraulic parameters in a hard rock aquifer using integrated surface geoelectrical method and pumping test data in southeast Guangdong, China." Geosciences Journal 25, no. 2: 223-242.
Subsurface geological formation is essential to validate design assumptions for the construction of deep engineering structures, especially in the weathered terrains. The geological formation can be delineated using resistivity values through an electrical survey. However, the subsurface resistivity alone is ambiguous to interpret the subsurface geological units. As part of an ongoing investigation to select the key methods towards this end, an integrated geophysical survey through a combination of electrical resistivity tomography (ERT), induced polarization (IP), magnetic method and joint profile method (JPM) was carried out in a weathered terrain of South Huizhou, China. Resistivity, IP, and magnetic data were obtained using a variety of survey parameters. Subsurface resistivity was calibrated with upfront boreholes lithology to constrain geological formation into four discrete layers such as topsoil cover with resistivity 2–3257 Ωm, highly weathered layer having resistivity 2–636 Ωm, partly weathered layer with resistivity range 448–1204 Ωm, and unweathered bedrock having resistivity 791–116,497 Ωm. The integration of ERT with IP, magnetic and JPM delineated four faults namely F1, F2, F3 and F4, and several localized fractures. The weathered layer, fractures and faults were marked as the weakest zones for engineering projects, whereas the unweathered fresh bedrocks were identified as the most appropriate locations for the construction of deep structures in the study area. The weakest zones unsuitable for engineering structures were delineated as the most appropriate places of groundwater occurrence in the studied area revealed by low resistivity ranging from 2 to 1204 Ωm and overlapped by low chargeability less than 14.8 ms. This non-invasive geophysical approach suggests the most suitable locations highly significant not only for the future construction of engineering structures but also the exploitation of groundwater resources in the investigated area.
Muhammad Hasan; Yanjun Shang; Weijun Jin; Gulraiz Akhter. An engineering site investigation using non-invasive geophysical approach. Environmental Earth Sciences 2020, 79, 1 -15.
AMA StyleMuhammad Hasan, Yanjun Shang, Weijun Jin, Gulraiz Akhter. An engineering site investigation using non-invasive geophysical approach. Environmental Earth Sciences. 2020; 79 (11):1-15.
Chicago/Turabian StyleMuhammad Hasan; Yanjun Shang; Weijun Jin; Gulraiz Akhter. 2020. "An engineering site investigation using non-invasive geophysical approach." Environmental Earth Sciences 79, no. 11: 1-15.
The snow and glacial resource of the Himalayan region are a major source of fresh water for Indus basin irrigation system on which sustenance of millions of people depends. In the context of recent growth in global warming, it has become inevitable to estimate snow and glacier melt to manage future water resource in this region. In the present study, snow and glacier melt runoff was estimated from various altitudinal ranges and under variable climate scenarios in Gilgit River Basin of Pakistan using an integrated modeling approach. The findings of the study revealed > 80% runoff contribution from 4000 to 5000 m elevation range in the Gilgit Basin. The scenario of temperature increase by 1 °C indicated 9% and 13% rise in annual and summer flows, while 3 °C rise in temperature exhibited an increase of 75% and 95% in annual and summer flows of the Gilgit River. As a result of 10% rise in precipitation, the Gilgit River indicated an increase of 48% in annual and 57% in summer flows. A shift in snow melting period was predicted from April to March due to rising warm temperature. Major contribution in the runoff was estimated from snowmelt followed by glacier melt and rainfall. Overall rising trend in snow cover area was observed in the basin, which support the fact of mass gaining behavior of the Karakoram glaciers. The increased summer flows expected under future climate change in this basin should be managed to fulfill the growing water demands of numerous communities living in the downstream in the future.
Sobia Ayub; Gulraiz Akhter; Arshad Ashraf; Mehwish Iqbal. Snow and glacier melt runoff simulation under variable altitudes and climate scenarios in Gilgit River Basin, Karakoram region. Modeling Earth Systems and Environment 2020, 6, 1607 -1618.
AMA StyleSobia Ayub, Gulraiz Akhter, Arshad Ashraf, Mehwish Iqbal. Snow and glacier melt runoff simulation under variable altitudes and climate scenarios in Gilgit River Basin, Karakoram region. Modeling Earth Systems and Environment. 2020; 6 (3):1607-1618.
Chicago/Turabian StyleSobia Ayub; Gulraiz Akhter; Arshad Ashraf; Mehwish Iqbal. 2020. "Snow and glacier melt runoff simulation under variable altitudes and climate scenarios in Gilgit River Basin, Karakoram region." Modeling Earth Systems and Environment 6, no. 3: 1607-1618.
Water is essential for life, agriculture, and industrialization; however, a rapid increase in population is constantly causing water scarcity and pollution in Pakistan. Mining activities produce the potential toxic element (PTE) accumulation, which lead to unnatural enrichment, ecological pollution, and environmental degradation. The ecological resources impeded by the PTEs cause serious abnormalities in the population through dermal contact, inhalation, and digestion. Mining induced anthropogenic activities are well-known causes of contamination of ecological resources. The produced effluents have drastic effects by changing the physical, chemical, and biological properties of the concerned resources. The Central Indus Basin is a well-known coal regime, where more than 160 mines are active at present. The samples that were collected from the mine water, groundwater, surface water, and the soil were analyzed by atomic absorption and elemental determination analysis (EDA) for an assessment of their quality and the presence of PTEs. The results were correlated with available quality standards, including the World Health Organization (WHO), National Standard of Drinking Water Quality (NSDWQ), World Wildlife Fund (WWF), and Sediment Quality Guidelines (SQGs). These analyses showed the noticeable anthropogenic concentration of PTEs, like iron, cadmium, sulphur, and copper, which can degrade the quality of resources in the Central Indus Basin and have adverse effects on human health. An excessive amount of acid mine drainage (AMD) draws attention to some suitable active or passive treatments for disposal from mines to avoid degradation of ecological resources in the Central Indus Basin of Pakistan.
Abdul Jabbar Khan; Gulraiz Akhter; Hamza Farooq Gabriel; Muhammad Shahid. Anthropogenic Effects of Coal Mining on Ecological Resources of the Central Indus Basin, Pakistan. International Journal of Environmental Research and Public Health 2020, 17, 1255 .
AMA StyleAbdul Jabbar Khan, Gulraiz Akhter, Hamza Farooq Gabriel, Muhammad Shahid. Anthropogenic Effects of Coal Mining on Ecological Resources of the Central Indus Basin, Pakistan. International Journal of Environmental Research and Public Health. 2020; 17 (4):1255.
Chicago/Turabian StyleAbdul Jabbar Khan; Gulraiz Akhter; Hamza Farooq Gabriel; Muhammad Shahid. 2020. "Anthropogenic Effects of Coal Mining on Ecological Resources of the Central Indus Basin, Pakistan." International Journal of Environmental Research and Public Health 17, no. 4: 1255.
A decline in surface water sources in Pakistan is continuously causing the over-extraction of groundwater resources which is in turn costing the saltwater intrusion in many areas of the country. The saltwater intrusion is a major problem in sustainable groundwater development. The application of electrical resistivity methods is one of the best known geophysical approaches in groundwater study. Considering the accuracy in extraction of freshwater resources, the use of resistivity methods is highly successful to delineate the fresh-saline aquifer boundary. An integrated geophysical study of VES and ERI methods was carried out through the analysis and interpretation of resistivity data using Schlumberger array. The main purpose of this investigation was to delineate the fresh/saline aquifer zones for exploitation and management of fresh water resources in the Upper Bari Doab, northeast Punjab, Pakistan. The results suggest that sudden drop in resistivity values caused by the solute salts indicates the saline aquifer, whereas high resistivity values above a specific range reveal the fresh water. However, the overlapping of fresh/saline aquifers caused by the formation resistivity was delineated through confident solutions of the D-Z parameters computed from the VES data. A four-layered unified model of the subsurface geologic formation was constrained by the calibration between formation resistivity and borehole lithologs. i.e., sand and gravel-sand containing fresh water, clay-sand with brackish water, and clay having saline water. The aquifer yield contained within the fresh/saline aquifers was measured by the hydraulic parameters. The fresh-saline interface demarcated by the resistivity methods was confirmed by the geochemical method and the local hydrogeological data. The proposed geophysical approach can delineate the fresh-saline boundary with 90% confidence in any homogeneous or heterogeneous aquifer system.
Muhammad Hasan; Yanjun Shang; Gulraiz Akhter; Weijun Jin. Delineation of contaminated aquifers using integrated geophysical methods in Northeast Punjab, Pakistan. Environmental Monitoring and Assessment 2019, 192, 12 .
AMA StyleMuhammad Hasan, Yanjun Shang, Gulraiz Akhter, Weijun Jin. Delineation of contaminated aquifers using integrated geophysical methods in Northeast Punjab, Pakistan. Environmental Monitoring and Assessment. 2019; 192 (1):12.
Chicago/Turabian StyleMuhammad Hasan; Yanjun Shang; Gulraiz Akhter; Weijun Jin. 2019. "Delineation of contaminated aquifers using integrated geophysical methods in Northeast Punjab, Pakistan." Environmental Monitoring and Assessment 192, no. 1: 12.
Assessment of fractured rock aquifers in many parts of the world is complicated given their strong heterogeneity. Delineation of the subsurface geological formation in the weathered terrain is essential for groundwater exploration. To achieve this goal, 2D electrical resistivity tomography (ERT) and self-potential (SP) in combination with joint profile method (JPM) and boreholes have been carried out to delineate the subsurface geological units, detect the fracture/fault zones in hard rock, monitor the groundwater flow, and estimate the groundwater reserves contained within the weathered terrain at a complex heterogeneous site of Huangbu, South Guangdong of China. The integration of resistivity images with the borehole lithology along three profiles delineates three subsurface distinct layers namely topsoil cover, weathered and unweathered layers. The incorporation of ERT and SP with JPM reveal five fractures/faults, i.e., F1, F2, F3, F4 and F5. 2D ERT models interpret the less resistive anomalies as the fractures/faults zones, and high resistive anomalies as the fresh bedrock. The inversion program based on the smoothness-constraint is used on the resistivity field data to get more realistic three layered model. SP measurements are obtained along the same electrical profiles which provide the negative anomalies clearly indicating the groundwater preferential flow pathways along the fracture/fault zones. Hydraulic parameters namely hydraulic conductivity and transmissivity were determined to estimate the groundwater resources contained within the fractures/faults. The integrated results suggest that the fractures/faults zones are most appropriate places of drilling for groundwater exploration in the investigated area. Geophysical methods coupled with the upfront borehole data provides better understanding about the conceptual model of the subsurface geological formations. The current investigation demonstrates the importance of the integrated geophysical methods as a complementary approach for groundwater assessment in the hard rock weathered areas.
Muhammad Hasan; Yan-Jun Shang; Wei-Jun Jin; Gulraiz Akhter. Investigation of fractured rock aquifer in South China using electrical resistivity tomography and self-potential methods. Journal of Mountain Science 2019, 16, 850 -869.
AMA StyleMuhammad Hasan, Yan-Jun Shang, Wei-Jun Jin, Gulraiz Akhter. Investigation of fractured rock aquifer in South China using electrical resistivity tomography and self-potential methods. Journal of Mountain Science. 2019; 16 (4):850-869.
Chicago/Turabian StyleMuhammad Hasan; Yan-Jun Shang; Wei-Jun Jin; Gulraiz Akhter. 2019. "Investigation of fractured rock aquifer in South China using electrical resistivity tomography and self-potential methods." Journal of Mountain Science 16, no. 4: 850-869.
Geophysical methods are effectively used to delineate intrusion boundary between the fresh and saline aquifers because of their intrinsic capability to assess the lateral variations in the pore-water salinity. In this study, an integrated geophysical approach of vertical electrical sounding (VES) and electrical resistivity tomography (ERT) has been conducted to delineate the contaminated aquifers in the Lower Bari Doab, Pakistan. Electrical resistivity tomography (ERT) using Schlumberger array with 5 m electrode spacing was conducted along eleven profiles at three selected sites (LBD1, LBD2 and LBD3) in the investigated area. The surface geoelectrical method was performed by sixty electrical resistivity soundings using the same array with maximum current electrode spacing (AB = 150 m). The integration of formation resistivity with ten boreholes reveals four discrete subsurface layers i.e., clay having saline aquifer, clay-sand containing brackish aquifer, sand with fresh aquifer and gravel-sand containing fresh aquifer. Estimation of Dar-Zarrouk Parameters (i.e., longitudinal resistivity, transverse resistance and longitudinal conductance) from different combinations of aquifer thickness and resistivity delineated the fresh, brackish and saline water zones with specific values range through mapping and graphical analysis. Geochemical method was performed on forty wells for main cations (K+, Na+, Ca2+ and Mg2+), anions (SO42−, Cl−, HCO3– and NO3−) and other parameters (As, EC, TDS and pH) to validate the results obtained from the geophysical methods. The fresh/saline aquifers delineated by the inclusion of ERT and geoelectrical method are in good agreement with those revealed by the physicochemical analysis and the local hydrogeological data. The results suggest that the use of non-invasive geophysical methods can reduce the number of expensive boreholes to obtain an interface between the fresh and saline water for the exploitation of fresh groundwater resources in any large area of homogeneous or heterogeneous aquifers.
Muhammad Hasan; Yanjun Shang; Gulraiz Akhter; Weijun Jin. Application of VES and ERT for delineation of fresh-saline interface in alluvial aquifers of Lower Bari Doab, Pakistan. Journal of Applied Geophysics 2019, 164, 200 -213.
AMA StyleMuhammad Hasan, Yanjun Shang, Gulraiz Akhter, Weijun Jin. Application of VES and ERT for delineation of fresh-saline interface in alluvial aquifers of Lower Bari Doab, Pakistan. Journal of Applied Geophysics. 2019; 164 ():200-213.
Chicago/Turabian StyleMuhammad Hasan; Yanjun Shang; Gulraiz Akhter; Weijun Jin. 2019. "Application of VES and ERT for delineation of fresh-saline interface in alluvial aquifers of Lower Bari Doab, Pakistan." Journal of Applied Geophysics 164, no. : 200-213.
The upsurge in agricultural food demand due to population explosion and urbanization has great impact on the quality of soil. Therefore, the present study was aimed to assess the contamination and pollution by selected metals (Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb and Zn) in the soil of typical rural and urban farmlands. The metal contents were quantified by atomic absorption spectrometry employing wet acid digestion methodology. In addition, physicochemical parameters (pH, redox potential, EC, TDS, organic matter, moisture, density, porosity and total alkalinity), anion levels (sulphate, chloride, nitrate and nitrite) and soil texture was also evaluated. Average concentrations of Co, Na, Ni, Pb and Zn were significantly higher in the rural soil, while Ca, Cu and Mg contents were considerably higher in the urban soil (p < 0.05). The correlation study revealed significantly divergent association among the metals in both categories of soil samples. Soil texture mostly revealed sandy loam nature of the soil with higher clay and silt contents in urban soil and elevated sand contents in rural soil which was predominantly Ca–Mg–HCO3 in composition. Significant anthropogenic contribution was shown by the cluster analysis while enrichment factors and contamination factors revealed severe to very high enrichment and moderate contamination of Cd and Pb in the soil. The study showed that elevated levels and anthropogenic enrichment of the metals in agricultural soil could pose serious health risks which should be addressed by appropriate management and sustainable agricultural practices.
Munir H. Shah; Asim Ilyas; Gulraiz Akhter; Amna Bashir. Pollution assessment and source apportionment of selected metals in rural (Bagh) and urban (Islamabad) farmlands, Pakistan. Environmental Earth Sciences 2019, 78, 189 .
AMA StyleMunir H. Shah, Asim Ilyas, Gulraiz Akhter, Amna Bashir. Pollution assessment and source apportionment of selected metals in rural (Bagh) and urban (Islamabad) farmlands, Pakistan. Environmental Earth Sciences. 2019; 78 (6):189.
Chicago/Turabian StyleMunir H. Shah; Asim Ilyas; Gulraiz Akhter; Amna Bashir. 2019. "Pollution assessment and source apportionment of selected metals in rural (Bagh) and urban (Islamabad) farmlands, Pakistan." Environmental Earth Sciences 78, no. 6: 189.
Groundwater is the main supply of fresh water in many parts of the world. The intrusion of saline water into the fresh water is a serious threat to groundwater resources. Delineation of fresh-saline aquifer zones is essential to exploit the potable fresh water. The conventional method to differentiate fresh-saline water interface is to collect and test groundwater samples from boreholes using a number of laboratory tests. However, such techniques are expensive and time consuming. A non-invasive geoelectrical method, in combination with borehole data and physicochemical analysis, is proposed to assess the fresh-saline aquifers. This investigation was conducted in Jahanian area of Pakistan with forty-five vertical electrical soundings (VES) using Schlumberger array, nine bore wells and fifty physicochemical samples. The fresh-saline aquifers are delineated by aquifer resistivity and Dar-Zarrouk parameters namely transverse unit resistance and longitudinal unit conductance. The aquifer potential of fresh-saline water zones is estimated by the aquifer parameters namely transmissivity and hydraulic conductivity. Integration of subsurface resistivity with hydrogeological information reveals the subsurface formation of five layered succession, that is, topsoil having dry strata with resistivity greater than 30 Ωm, clay containing saline water with resistivity less than 15 Ωm, clay-sand with brackish water having resistivity between 15 and 25 Ωm, sand containing fresh water with resistivity ranging from 25 to 45 Ωm and gravel-sand having fresh water with resistivity greater than 45 Ωm. The geoelectrical columns and geological cross-sections constructed by the aquifer resistivity provide effectiveness of the interpretations for the evaluation of fresh-saline aquifers. The results of physicochemical analysis using WHO guideline validate the fresh-saline aquifer zones delineated by the geophysical method. This investigation contributes towards predicting the fresh-saline water interface using inexpensive geoelectrical method.
Muhammad Hasan; Yanjun Shang; Gulraiz Akhter; Weijun Jin. Delineation of Saline-Water Intrusion Using Surface Geoelectrical Method in Jahanian Area, Pakistan. Water 2018, 10, 1548 .
AMA StyleMuhammad Hasan, Yanjun Shang, Gulraiz Akhter, Weijun Jin. Delineation of Saline-Water Intrusion Using Surface Geoelectrical Method in Jahanian Area, Pakistan. Water. 2018; 10 (11):1548.
Chicago/Turabian StyleMuhammad Hasan; Yanjun Shang; Gulraiz Akhter; Weijun Jin. 2018. "Delineation of Saline-Water Intrusion Using Surface Geoelectrical Method in Jahanian Area, Pakistan." Water 10, no. 11: 1548.
Climate change is expected to have a significant impact on the Himalayan region, which may ultimately affect the water security and agriculture productivity in the region. Investigations of hydrologic regimes and their linkage to climatic trends are therefore gaining importance to reduce vulnerability of growing implications in the region. In the present study, the eWater source software implementation of GR4JSG snow melt model was used for snow melt runoff modeling of the Astore river basin, western Himalayas. The model calibration and validation indicated a close agreement between the simulated and observed discharge data. The scenario of 0.9 °C increase in temperature indicated 33% rise in the river discharge, while an increase of 10% in precipitation may exaggerate the river flows by 15%. The scenario of 100% increase in glaciated area showed 41% increase in the Astore river discharge. On the other hand, reduction of 50% glacier cover may result in 34% decline in the river discharge, while 0% glacier coverage may reduce the river discharges by 49% from that of the base year 2014. It is essential to develop a long-term water resource monitoring process and adapt water management systems taking into account the socio-economic and ecological complexities of the region.
Mehwish Iqbal; Gulraiz Akhter; Arshad Ashraf; Sobia Ayub. Snowmelt runoff assessment and prediction under variable climate and glacier cover scenarios in Astore River Basin, Western Himalayas. Arabian Journal of Geosciences 2018, 11, 568 .
AMA StyleMehwish Iqbal, Gulraiz Akhter, Arshad Ashraf, Sobia Ayub. Snowmelt runoff assessment and prediction under variable climate and glacier cover scenarios in Astore River Basin, Western Himalayas. Arabian Journal of Geosciences. 2018; 11 (18):568.
Chicago/Turabian StyleMehwish Iqbal; Gulraiz Akhter; Arshad Ashraf; Sobia Ayub. 2018. "Snowmelt runoff assessment and prediction under variable climate and glacier cover scenarios in Astore River Basin, Western Himalayas." Arabian Journal of Geosciences 11, no. 18: 568.
Launched in 2014, the Global Precipitation Measurement (GPM) mission aimed at ensuring the continuity with the Tropical Rainfall Measuring Mission (TRMM) launched in 1997 that has provided unprecedented accuracy in Satellite Precipitation Estimates (SPEs) on the near-global scale. Since then, various SPE versions have been successively made available from the GPM mission. The present study assesses the potential benefits of the successive GPM based SPEs product versions that include the Integrated Multi–Satellite Retrievals for GPM (IMERG) version 3 to 5 (–v03, –v04, –v05) and the Global Satellite Mapping of Precipitation (GSMaP) version 6 to 7 (–v06, –v07). Additionally, the most effective TRMM based SPEs products are also considered to provide a first insight into the GPM effectiveness in ensuring TRMM continuity. The analysis is conducted over different geomorphic and meteorological regions of Pakistan while using 88 precipitations gauges as the reference. Results show a clear enhancement in precipitation estimates that were derived from the very last IMERG–v05 in comparison to its two previous versions IMERG–v03 and –v04. Interestingly, based on the considered statistical metrics, IMERG–v03 provides more consistent precipitation estimate than IMERG–v04, which should be considered as a transition IMERG version. As expected, GSMaP–v07 precipitation estimates are more accurate than the previous GSMaP–v06. However, the enhancement from the old to the new version is very low. More generally, the transition from TRMM to GPM is successful with an overall better performance of GPM based SPEs than TRMM ones. Finally, all of the considered SPEs have presented a strong spatial variability in terms of accuracy with none of them outperforming the others, for all of the gauges locations over the considered regions.
Frédéric Satgé; Yawar Hussain; Marie-Paule Bonnet; Babar M. Hussain; Hernan Martinez-Carvajal; Gulraiz Akhter; Rogério Uagoda. Benefits of the Successive GPM Based Satellite Precipitation Estimates IMERG–V03, –V04, –V05 and GSMaP–V06, –V07 Over Diverse Geomorphic and Meteorological Regions of Pakistan. Remote Sensing 2018, 10, 1373 .
AMA StyleFrédéric Satgé, Yawar Hussain, Marie-Paule Bonnet, Babar M. Hussain, Hernan Martinez-Carvajal, Gulraiz Akhter, Rogério Uagoda. Benefits of the Successive GPM Based Satellite Precipitation Estimates IMERG–V03, –V04, –V05 and GSMaP–V06, –V07 Over Diverse Geomorphic and Meteorological Regions of Pakistan. Remote Sensing. 2018; 10 (9):1373.
Chicago/Turabian StyleFrédéric Satgé; Yawar Hussain; Marie-Paule Bonnet; Babar M. Hussain; Hernan Martinez-Carvajal; Gulraiz Akhter; Rogério Uagoda. 2018. "Benefits of the Successive GPM Based Satellite Precipitation Estimates IMERG–V03, –V04, –V05 and GSMaP–V06, –V07 Over Diverse Geomorphic and Meteorological Regions of Pakistan." Remote Sensing 10, no. 9: 1373.
Knowledge of hydraulic parameters (hydraulic conductivity and transmissivity) is essential for the delineation of groundwater potential zones. Conventionally, these parameters are measured using pumping tests carried out on boreholes. However, pumping tests are costly, labor intensive and require a considerable amount of equipments. The integration of geophysical methods with pumping tests provides efficient and cost effective alternative to calculate hydraulic parameters. Fifty electrical resistivity soundings were carried out in the study area using Schlumberger inter‐electrode configuration to obtain hydraulic characteristics that are estimated through the pumping tests. To apply this approach successfully, sufficient number of boreholes are used. Part of the boreholes, in which pumping tests were carried out, is used for both to constrain resistivity inversions and to establish the empirical relationship between the interpreted geophysical and hydraulic parameters. The rest of the boreholes without pumping tests are still used for constraining the inversions. Initially, aquifer parameters were measured using pumping tests at twelve water wells. Afterwards, transmissivity (T) and hydraulic conductivity (K) were correlated with transverse resistance (Tr) and the bulk resistivity (ρo) of the aquifer at other sites where pumping tests had not been conducted. In this way, the entire study area was covered to assess the groundwater reserves. The hydraulic properties obtained by the geophysical method fit pretty well to both the pumping and physicochemical data of the investigated area. The integrated study reveals five layers (i.e., topsoil, clay, clay sand, sand and gravel sand) and three potential zones (i.e., high, medium and low potential aquifer zones) with specific ranges of T, K, Tr and ρo. The results suggest that, in case of sparse well data, the aquifer parameters can be estimated using the relations depending on the specifications of the area. This article is protected by copyright. All rights reserved
Muhammad Hasan; Yanjun Shang; Gulraiz Akhter; Weijun Jin. Evaluation of groundwater potential in Kabirwala area, Pakistan: A case study by using geophysical, geochemical and pump data. Geophysical Prospecting 2018, 66, 1737 -1750.
AMA StyleMuhammad Hasan, Yanjun Shang, Gulraiz Akhter, Weijun Jin. Evaluation of groundwater potential in Kabirwala area, Pakistan: A case study by using geophysical, geochemical and pump data. Geophysical Prospecting. 2018; 66 (9):1737-1750.
Chicago/Turabian StyleMuhammad Hasan; Yanjun Shang; Gulraiz Akhter; Weijun Jin. 2018. "Evaluation of groundwater potential in Kabirwala area, Pakistan: A case study by using geophysical, geochemical and pump data." Geophysical Prospecting 66, no. 9: 1737-1750.
Conventional seismic interpretation provides subsurface geometric information, while quantitative seismic interpretation can provide lithologic and fluid information, including saturations, porosity, density, Poisson’s ratio and other elastic parameters. Rock physics is the main science behind quantitative interpretation and includes a number of transforms, in the form of empirical relations, for the computation of various rock properties. In addition, crossplot templates of these properties help in facies modeling and reservoir characterization. This paper presents rock physics transforms between compressional velocity, shear velocity, density, porosity, resistivity and gamma ray radiation for Cretaceous to Miocene strata in the Indus offshore area, Pakistan. These transforms are empirical relations established through regression analysis between various petrophysical parameters. Logs from twelve wells have been used in the analysis to give a good representation of rock properties in the area. Most of the relations have a linear correlation coefficient above 0.74 and therefore can be used reliably in quantitative interpretation of seismic data.
Anees Ahmad Bangash; Khalid Amin Khan; Gulraiz Akhter. Rock Physics Relations Derived from Petrophysical Logs for Indus Offshore Area, Pakistan. Arabian Journal for Science and Engineering 2018, 44, 409 -416.
AMA StyleAnees Ahmad Bangash, Khalid Amin Khan, Gulraiz Akhter. Rock Physics Relations Derived from Petrophysical Logs for Indus Offshore Area, Pakistan. Arabian Journal for Science and Engineering. 2018; 44 (1):409-416.
Chicago/Turabian StyleAnees Ahmad Bangash; Khalid Amin Khan; Gulraiz Akhter. 2018. "Rock Physics Relations Derived from Petrophysical Logs for Indus Offshore Area, Pakistan." Arabian Journal for Science and Engineering 44, no. 1: 409-416.
The growing trend in global warming has impacted the hydrological system of the Indus River system. The variations in climate have influenced not only the local but also the regional behavior of groundwater system in the Indus River basin. It would also be crucial to investigate characteristics and behavior of this resource in order to ensure safe yield for irrigation, industry, and sustaining livelihood of millions of people of Indus area. A good knowledge of the problem and analysis of various components of the hydrological system are thus essential to achieve optimum groundwater management goals for sustaining agriculture development. The numerical groundwater flow model—Feflow—was calibrated to simulate groundwater flow behavior in upper Chaj Doab, Indus basin, during 1985–2005. The model had predicted an average decline of about 0.96 m in groundwater levels during the calibrated period and further reduction up to year 2020. A major breakthrough of groundwater depletion was observed in year 1999 when the last drought prevailed for over 3–4 years in this region. Major causative factors of watertable decline may include decrease in surface water for groundwater recharge, variability and change in rainfall pattern, and overexploitation of groundwater. The situation has resulted not only in exaggerating the cost of groundwater pumping, but also in abandoning existing wells. The integration of groundwater flow modeling and geoinformatic techniques proved helpful in analyzing the resource situation as well as vulnerability of the groundwater system to influential factors like climate change. As the country is already water stressed and predicted to face water scarcity in future, there is a need to monitor the groundwater system periodically on long-term basis to cope with food and water security issues in the Indus basin in future.
Arshad Ashraf; Zulfiqar Ahmad; Gulraiz Akhter. Monitoring Groundwater Flow Dynamics and Vulnerability to Climate Change in Chaj Doab, Indus Basin, Through Modeling Approach. Thermal Springs and Geothermal Energy in the Qinghai-Tibetan Plateau and the Surroundings 2018, 593 -611.
AMA StyleArshad Ashraf, Zulfiqar Ahmad, Gulraiz Akhter. Monitoring Groundwater Flow Dynamics and Vulnerability to Climate Change in Chaj Doab, Indus Basin, Through Modeling Approach. Thermal Springs and Geothermal Energy in the Qinghai-Tibetan Plateau and the Surroundings. 2018; ():593-611.
Chicago/Turabian StyleArshad Ashraf; Zulfiqar Ahmad; Gulraiz Akhter. 2018. "Monitoring Groundwater Flow Dynamics and Vulnerability to Climate Change in Chaj Doab, Indus Basin, Through Modeling Approach." Thermal Springs and Geothermal Energy in the Qinghai-Tibetan Plateau and the Surroundings , no. : 593-611.
Gulraiz Akhter; Younis Khan; Anees Ahmad Bangash; Faisal Shahzad; Yawar Hussain. Petrophysical relationship for density prediction using Vp & Vs in Meyal oilfield, Potwar sub-basin, Pakistan. Geodesy and Geodynamics 2018, 9, 151 -155.
AMA StyleGulraiz Akhter, Younis Khan, Anees Ahmad Bangash, Faisal Shahzad, Yawar Hussain. Petrophysical relationship for density prediction using Vp & Vs in Meyal oilfield, Potwar sub-basin, Pakistan. Geodesy and Geodynamics. 2018; 9 (2):151-155.
Chicago/Turabian StyleGulraiz Akhter; Younis Khan; Anees Ahmad Bangash; Faisal Shahzad; Yawar Hussain. 2018. "Petrophysical relationship for density prediction using Vp & Vs in Meyal oilfield, Potwar sub-basin, Pakistan." Geodesy and Geodynamics 9, no. 2: 151-155.