http://hdl.handle.net/123456789/16974 Sat, 04 Apr 2026 12:26:44 GMT 2026-04-04T12:26:44Z http://hdl.handle.net/123456789/18657 Seismic Driven Thin Reservoir Facie Classification Using Advanced Machine Learning Algorithms: A Research On Lower Ranikot Sandstone Reservoir, Kirthar Foldbelt, Lower Indus Basin, Pakistan Umar Manzoor, 01-286202-002 This study addresses the crucial challenge of characterizing thin gas sand reservoirs in the Lower Ranikot/Khadro Formation of Pakistan's Lower Indus Basin, a reservoir with varying thicknesses 4 to 7 m below seismic resolution. Previous studies have struggled to produce precise results due to reservoir heterogeneity, data limitations, and associated uncertainties. An optimized, integrated approach, combining seismic attributes, petrophysical properties, advanced machine learning (ML) algorithms, and continuous wavelet transform (CWT) addresses thin gas sand facies and pore pressure challenges comprehensively. Among several employed ML algorithms gradient boosting regressor (GBR) accurately predicted thin sands (>90%), reducing uncertainty in hydrocarbon-bearing sand distribution. A delicate ML approach has been broadly applied to analyze the potential and robustly interpret well-logs while addressing the associated challenges. Support vector machine (One-class-SVM) helps to reduce outliers with great certainty while the missing log's sonic and density are precisely predicted via GBR and extra tree regressor (ETR) with the highest R2 respectively. Likewise, random forest regressor (RFR) performed exceptionally well for water saturation modeling expressing the highest 0.93 correlation among ML and conventional results. Finally, the decision tree classifier (DTC) modeled reservoir facies with the best 91% accuracy and 0.935 F1 measures at the blind well. Additionally, an optimized workflow generates high-frequency acoustic impedance synthetics by utilizing a deep neural network (DNN) integrated with CWT components at the reservoir level vis-a-vis validating the results with existing geological facies to resolve thin beds without introducing noise. The shale layers of the formation are quite problematic and complex geological variations exhibit pore pressure discrepancy making drilling operations crucial. Among all conventional methods for pore pressure prediction, GBR integrated with CWT has provided very good results after validation. The study characterizes reservoirs below seismic resolution, enabling more efficient resource exploration and development. It outperforms previously done conventional approaches by delivering higher accuracy, reducing uncertainty, and unlocking valuable insights using advanced ML and CWT techniques. It offers broad applicability to other complex, thin-bed reservoirs worldwide, optimizing field development and maximizing hydrocarbon recovery. Supervised by Dr. Muhsan Ehsan Mon, 01 Jan 2024 00:00:00 GMT http://hdl.handle.net/123456789/18657 2024-01-01T00:00:00Z http://hdl.handle.net/123456789/16980 Overexploitation Of Groundwater And Its Impact On Quality Of Water In Winder Balochistan : An Environmental Geophysical Approach Muhammad Irfan, 02-283161-004 In Winder Town District Lasbela, Balochistan, groundwater is at a vulnerable stage due to overexploitation mainly for irrigation activities. It is situated 80 km in the north-west of Karachi city near the Makran Coast. The research was conducted through integrated geophysical and hydro-geochemical approach to map the subsurface groundwater and estimate the aquifer parameters. The study also highlighted the spatial variation for hydro-geophysical parameters integrated with hydrochemistry and hydrogeology to assess the overexploitation impact and groundwater quality of study area. There have been no integrated scientific studies conducted and documented for sustainable groundwater development of the area. Previous research on hydrogeochemistry of groundwater and data analysis were used for comparison and to develop temporal variation in the quality of water. The geophysical electrical resistivity method was selected; utilizing vertical electrical sounding (VES), and Schlumberger electrode arrangement to map the potential aquifer and other hydrogeological parameters. PASI 16-GLN earth resistivity meter was utilized to acquire 27 points, of vertical electrical sounding (VES). The maximum lateral spacing of current electrode has been kept at 300 meters (AB), to delineate electrical properties up to 150 meters’ depth. The resistance values acquired in the study area were multiplied with the Geometrical Factor (K) to estimate apparent resistivity. Finally, obtained field data from the geophysical survey was processed using computer inversion program IPI2Win developed by Moscow State University, Russia. The geophysical results delineate five layer of variable resistivity; layer 1 (1.5-3.5 m) resistivity ranges from 2-38 Ωm and an average value is 17.5 Ωm. This shows that the resistivity is higher toward the western side of the RCD highway due to dry and unsaturated sand dunes deposits. The lowervii resistivity pattern in east and the central part near the Winder River of the study area depict sandy clay and clay. In layer 2 (3.2-14.2 m) resistivity ranges from 6.32-42 Ωm and the average value is 23 Ωm. The range in the north-east of study area shows higher resistivity interpreted as sandy gravel whereas the south-west & north-west comprise sand deposits. The layer 3 (13-51 m) resistivity varies from 14-50.4 Ωm and the mean value is 29 Ωm. Layer 4 (50.4-114 m) resistivity ranges from 13.5-51.6 Ωm and an average value is 31.5 Ωm. Layer 5 resistivity value ranges from 14.1-51.4 Ωm and an average value is 27.35 Ωm. Layer 3,4 and 5 show higher resistivity in central and eastern region where as the western side shows low resistivity zones. The layer 4 and 5 are saturated and low resistivity depicts the brackish water condition toward the western side, the higher resistivity closure along the Winder River is delineated as the high potential of low TDS water zone. Due to over-pumping of groundwater in Winder Balochistan the water table declined from 15 to 45 meters. The freshwater hand pump near the coastal belt is abandoned and deeper water is more saline. In the vicinity of agriculture farm groundwater, TDS ranges from 1000-2800 ppm. The sample of groundwater from the tube well in the study area provides the spatial distribution of groundwater quality. The analysis of 94 groundwater samples were carried out for physiochemical parameters. Trace elements for the selected samples were also assessed for comparative analysis with published research of 2013. The hydrochemical analysis shows that the dominant hydro facies type is NaCl, Ca-Cl and MgSO4. The HEF-D plot, Gibbs diagram, Stiff plot, Piper diagram, Ionic ratio and statistical analysis of physiochemical analysis suggest that seawater intrusion plays a vital part in groundwater recharge due to aquifer overexploitation. The physiochemical analysis shows that the Na+>Ca2+>Mg2+>K+ (meq/l) for the cation and Cl->HCO3->SO42- (meq/l) for anions in groundwater of study area. The nitrate contamination >50 mg/l concentration was observed in the samples of Winder which can be the result of livestock activity, agriculture activity and some extent to domestic use of water. The results of the present study also compared with the previous research on groundwater which represents, decline in groundwater quality. The hydro-chemical parameters of previously published data show that composition was mainly controlled by the Mor and Pab ranges in north-eastern part of the study area. The average value of the present study for pH is 7.23, Na+ 331 mg/l, Cl- 522 mg/l, SO42- 307mg/l, 50% of sample shows high salinity hazard, the ionic ratio of HCO3-/Cl- is 0.43 and Na/Cl is 0.97 depict the impact of seawater intrusion in groundwater. The estimated irrigation water qualityviii parameter shows the average value of RSC is -7.6 (suitable), Na% 50.1, SAR 5.8 (suitable), MAR 50.6, PS 18 and PI 133.3 (good). The increase in the pH value of groundwater decreased the concentration of trace element of study area. The estimated average values are very close to permissible limit and maximum value in most of the samples exceeds the irrigation water quality standard and deteriorates the soil and crops of the area. The integrated geophysical and hydrochemical parameter maps can be utilized to categorize the low-high risk zone for agriculture activities and domestic use of water. The pumping of groundwater should be stopped from tube wells near to the coast such as UF, UG, UN, US, UD, UL, UR, UG, UT, UP, PS, KA, KZ, KT, KA and KQ. The study area is strategically very important regarding China Pakistan Economic Corridor. Urbanization and industrialization are increasing rapidly and directly stress groundwater production for agricultural activity eventually the impacts are estimated from the present study. The sustainable development of Winder is highly dependent on groundwater effective management, mitigation of seawater intrusion and government policies to exploit groundwater. Supervised by Dr. Salma Hamza Sun, 01 Jan 2023 00:00:00 GMT http://hdl.handle.net/123456789/16980 2023-01-01T00:00:00Z http://hdl.handle.net/123456789/16979 Spatial Analysis Of Groundwater Quality Using Geophysical And Geochemical Approach In Uthal, Balochistan Shaista Mahmud, 02-283161-003 Uthal is located in Lasbela District in Pakistan's Balochistan province. It has an arid to semi-arid climate, and the main source of fresh water for domestic and agricultural purposes is groundwater. To determine the spatial distribution of groundwater and its quality, an electrical resistivity survey was carried out using the schlumberger array. The PASI Electrical Resistivity Imaging System was utilized to examine 25 stations in the study area, to investigate a depth of 150 meter. IPI2win software was used for curve matching to assess the measured geoelectrical characteristics. The Dar Zarrouk parameters were computed after identifying five geoelectrical layers. The resistivity of the topmost, thinnest layer of unconsolidated material ranged from 600 to 2600 Ωm. The resistivity of the second layer of unconsolidated sand and gravel ranged from 50 to 11500 Ωm; that of the third layer of dry sand and clay was up to 200 Ωm; that of the fourth layer showed a thick freshwater zone with a resistivity between 75 and 100 Ωm; and that of the layer after that showed a thick layer of sand and clay with fresh water had a resistivity of between 48 and 90 Ωm. The Dar Zarrouk parameters estimated for longitudinal unit conductance (S), ranges from 0.1 to 1.65 mho, transverse unit resistance (T), which is larger than 25000 Ωm2, longitudinal resistance (RS), which ranges from 50 to 1350 Ωm, and transverse resistivity (RT), which ranges from 22 to 1150 Ωm. The ERS data and Dar Zarrouk characteristics identified the freshwater zones in the subsurface. Small pockets of saline water were found in few near surface zones due to evaporation owing to the arid and semiarid surface conditions. There has been no indication of seawater intrusion, from the ERS data and Dar Zarrouk characteristics. To confirm the findings of electrical resistivity data, groundwater samples from 100 sites were collected from the study area. Chemical analyses were performed for major cations and anions present in water. In addition, to study the characteristic of water, trace element analysis was also performed on the samples. The major cations and anions of the study area are, Sodium (Na) (50.7 to 1858 mg/l), Chloride (Cl) (6.2 to 2150 mg/l), Potassium (K) (1 to 34 mg/l), Calcium (Ca) (19 to 857 mg/l), Magnesium (Mg) (5.77 to 281 mg/l), Bicarbonates (HCO3) (58 to 860 mg/l), Sulfate (SO4)(44 to 4411 mg/l) & NO3 (48 to 854). The trace elements are, Aluminum (Al) (5 to 756 µg/l), Chromium (Cr) (0.5 to 114 µg/l), Cadmium (Cd) (0 to 24 µg/l), Chromium (Cu) (0.05 to 354 µg/l), Manganese (Mn) (2 to 675 µg/l), Nickle (Ni) (0 to 412 µg/l), Lead (Pb) (1.5 to 79 µg/l), Zinc (Zn) (5 to 801 µg/l) and Arsenic (As), Cobalt (Co), & Titanium (Ti) below detection limits. Estimates were made for the physical parameters; alkalinity, total dissolved solids, and electric conductance parameters. The concentration of main cations, anions, and trace elements are within the permissible limits as per WHO standards, except for a few sample points. The sedimentary rocks and the mineralization of the Bela Ophiolites exposed in the study area are the main sources of these cations, anions, and trace elements. The study integrated the Dar zarrouk parameters, as calculated from the electrical resistivity values (ρ), and the corresponding Total Dissolved Salts (TDS) values. The study area has been divided into four zones namely, very good potential (TDS ˂ 500 mg/l & ρ from 200 to 1500 Ωm), good potential (TDS from 501 to 1000 mg/l & ρ from 100 to 200 Ωm), fair potential (TDS from 1001 to 2000 mg/l & 20 to 100 Ωm) and poor potential zones (TDS ˃ 2000 mg/l & ρ ˂20 Ωm). The current study has provided the quantitative legend of the area. This legend can be quantified and applied to surrounding semi-arid to arid of the area. This is valid for reservoir modeling and changes in hydrofacies and trend analysis for good water management practices. Supervised by Dr. Salma Hamza Sun, 01 Jan 2023 00:00:00 GMT http://hdl.handle.net/123456789/16979 2023-01-01T00:00:00Z