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Investigation of fractured rock aquifer in South China using electrical resistivity tomography and self-potential methods

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Journal of Mountain Science 2019年第4期16卷 850-869页

作者： Muhammad HASAN SHANG Yan-jun JIN Wei-jun gulraiz akhter Key Laboratory of Shale Gas and Geoengineering Institute of Geology and Geophysics Chinese Academy of Sciences Institutions of Earth Science Chinese Academy of Sciences University of Chinese Academy of Sciences Department of Earth Sciences Quaid-i-Azam University

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., F_1, F_2, F_3, F_4 and F_5. 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 a

关键词： Electrical resistivity tomography Self-potential Groundwater flow Hard rock Heterogeneity Hydraulic parameters

Petrophysical relationship for density prediction using Vp & Vs in Meyal oilfield, Potwar sub-basin, Pakistan

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Geodesy and Geodynamics 2018年第2期9卷 151-155页

作者： gulraiz akhter Younis Khan Anees Ahmad Bangash Faisal Shahzad Yawar Hussain Department of Earth Sciences Quaid-i-Azam University Key Laboratory of Mineral Resources Institute of Geology and Geophysics Chinese Academy of Sciences National Centre of Excellence in Geology (NCEGS) University of Peshawar Research and Development Department Department of Civil and Environmental Engineering University of Brasilia

Conventional petrophysical investigations are based on P-wave seismic velocity analysis to predict density information, while ignoring the important S-wave velocity. This study is based on S-wave velocity analysis of density estimation of Meyal Oil Field(Potwar Plateau, Pakistan), which reveals a very high correlation(R=0.87) between predicted and actual density. Since the availability of S-wave velocity(Vs) data increases, it’s highly appreciable to take into account the contribution of Vs in improvement of density estimates. This investigation only focuses on driving new constants(a = 1.92 and b = 0.186) for Gardner’s relationship to estimate density of pure carbonates(Vsh< 10%) in the study area, where the traditional model gave poorer density predictions. The proposed empirical expression with locally extracted unknowns from well log data proved its ability in terms of density prediction(showing very close agreement with measured densities) and best fitting the datasets at low as well as high density values when compared with Gardner’s equation. Based on our analysis, the exploratory study neither intends to replace the well established density estimation models nor to extend information over what information can possibly be extractable from Vp. However, our research does stimulate the growing use of Vs and importance of local unknown constants especially in carbonates reservoir interval to avoid misuse of most widely used Gardner relation in all geological settings.

关键词： Shale Gardner Potwar Carbonates S-Waves

GPS Workstation—A Static Point Averaging and Tracks Mapping Application

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Positioning 2013年第1期4卷 57-64页

作者： Khalid Amin Khan gulraiz akhter Department of Earth Sciences Quaid-i-Azam University Islamabad Pakistan K-tron Research Inc. Rawalpindi Pakistan

This paper describes GPS Workstation, a general purpose navigation software which requires a low-cost GPS connected to the computer. It provides an integrated display of positioning data along with satellite positions, their signal strengths and data quality parameters. The software can be used for static point averaging of GPS data to get more precise positioning and real-time mapping of roads and tracks. It supports output of data in keyhole markup language (KML) as well as other formats for visualization of acquired data on Google Earth and geographic information systems. It can also be used to determine geo-referencing errors in Google Earth imagery for an area and can compensate the error by applying a constant X, Y shift. The software is available for distribution under the free software license.

关键词： GPS Real-Time Mapping Google Earth Data Averaging

GIS as Project Manager in Geophysical Applications Software

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Journal of Geographic Information System 2011年第2期3卷 166-172页

作者： Khalid Amin Khan gulraiz akhter Zulfiqar Ahmad 不详

The changing trends in information technology have greatly influenced the role of GIS in spatial data management, analysis, processing and presentation. It has evolved from the conventional cartography and image processing to advanced 3D visualization and dynamic graphics tools. Due to this evolving nature of GIS, it has found wide applications in a number of diverse fields. Geophysical exploration projects involve data acquisition at hundreds of spatial locations resulting in large number of datasets. It takes a great deal of time to manage all these datasets during data processing and interpretation. This paper presents the use of GIS as an effective project management tool, providing an interactive data access interface in compute intensive geophysical processing applications. A reusable GIS software component is presented which can be used by geophysical applications to manage their datasets. A practical example is included to demonstrate the implementation of this GIS component as an embedded Project Manager in a seismic refraction software.

关键词： GIS Project Manager Interactive Interface Database Geophysics

Modelling the Spatial Distribution of Arsenic in Water and Its Correlation with Public Health, Central Indus Basin, Pakistan

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Journal of Geoscience and Environment Protection 2016年第2期4卷 18-25页

作者： Yawar Hussain Adil Dilawar Sadia Fida Ullah gulraiz akhter Hernan Martinez-Carvajal Muhammad Babar Hussain Abdul Qayyum Aslam Department of Civil and Environmental Engineering University of Brasilia Brasilia Brazil Department of Physics University of Sargodha Sargodha Pakistan Department of Biological Sciences University of Brasilia Brasilia Brazil Department of Earth Sciences Quaid-i-Azam University Islamabad Pakistan Faculty of Mines National University of Colombia at Medellín Medellín Colombia Department of Theoretical and Astrophysics Xiamen University Xiamen China College of Earth and Environmental Sciences University of the Punjab Lahore Pakistan

Like India, Bangladesh and China, Pakistan also has some regions where concentration of Arsenic in water has crossed the WHO safe drinking water limits, 10 ppb. Presence of Arsenic in drinking water is causing serious human health issues for the local residents of Sindh and southern Punjab, which needs serious attention. The present study is focused on the spatial distribution of Arsenic in groundwater and its relationship with the major reported human diseases at settlement level of District Layyah. Data collection is done by taking water samples from hand pumps and health issues reported at the local health care centers adjoining to that sampling pump. The spatial distribution of Arsenic concentration in groundwater is done by using Inversion Distance Weight (IDW) technique. Arsenic Risk Index (ARI) is developed based of WHO health standards, and then used to divide study area into two Arsenic Risk Zones as no risk and high risk with As values less or equal to 10 ng·ml-1 and greater than 10 ng·ml-1, respectively . In the final step these zones were correlated with the diseases at village level. The results show that, Arsenic is high near the Indus River and it decreases in central and eastern parts towards Chenab River. Same trend of Indo-Chenab Arsenic gradient is followed by skin diseases among the people especially, in tehsil Layyah and tehsil Koror. It is concluded that high Arsenic amount in water and skin diseases are highly dependent on the recharge from Indus River.

关键词： Arsenic GIS Human Health IDW Indus Basin Layyah

Growth and Haematological Responses of Growing Broiler Chickens （3-6 weeks） to Phosphorus and Phytase Supplementation in Low Nutrient Diet

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Journal of Agricultural Science and Technology(A) 2013年第11期3卷 912-919页

作者： Mirza Muhammad Haroon Mushtaq Muhammad Sarwar Tariq Mushtaq gulraiz Ahmad Rana Parvin Jihyuk Kim Agro Visions Faisalabad 38800 Pakistan Poultry Science Division National Institute of Animal Science Cheonan 331-801 Republic of Korea Institute of Animal Nutrition and Feed Technology University of Agriculture Faisalabad 38000 Pakistan Sadiq Feeds (Pvt.) Ltd. Rawalpindi 46000 Pakistan

The experiment was conducted to evaluate the low phosphorus diets supplemented with different sources of phytase in low metabolizable energy （ME） and crude protein （CP） diets in broilers. Four levels of non-phytate phosphorus （NPP）（0.33%, 0.36%, 0.39% and 0.42% of the diet） were employed in six dietary treatments in such a way that the least level of NPP （0.33%） was supplemented with two phytase enzymes namely 6-phytase （Natuphos-5,000） and 3-phytase （Sunphase） along with low nutrient composition viz. 2750 kcal ME/kg and CP 18% in growing phase （21 d-42 d）. A total of 1,400 birds were exposed to six treatments in three replicates except for the phytase supplemented diets which were replicated four times each. Non-significant results are obtained from all performance parameters （body weight gain, feed intake and feed gain） and serum minerals （calcium and phosphorus） between 21 days to 42 days. Non-significant results are seen among all treatments; even supplementation of both types of enzymes did not affect the overall results. The results of the present study demonstrate 0.33% P level without phytase are sufficient in low ME and CP diets.

关键词： Non-phytate phosphorus 3-phytase 6-phytase broiler.