The Meyal oil field (MOF) is among the most important contributors to Pakistan’s oil and gas industry. Northern Pakistan’s Potwar Basin is located in the foreland and thrust bands of the Himalayan mountains. The current research aims to delineate the hydrocarbon potential, reservoir zone evaluation, and lithofacies identification through the utilization of seven conventional well logs (M-01, M-08, M-10, M-12, M-13P, and M-17). We employed the advanced unsupervised machine-learning method of self-organizing maps for lithofacies identification and the novel Quanti Elan model technique for comprehensive multimineral evaluation. The shale volume, porosity, permeability, and water saturation (petrophysical parameters) of six wells were evaluated to identify the reservoir potential and prospective reservoir zones. Well-logging data and self-organizing maps were used in this study to provide a less costly method for the objective and systematic identification of lithofacies. According to the SOM and Pickett plot analyses, the zone of interest is mostly made up of pure limestone oil zone, whereas the sandy and dolomitic behavior with a mixture of shale content shows non-reservoir oil–water and water zones. The reservoir has good porosity values that range from 0 to 18%, but there is a high water saturation of up to 45% in reservoir production zones. The presence of shale in the entire reservoir interval has a negative effect on the permeability value, but the petrophysical properties of the Meyal oil reservoir are good enough to permit hydrocarbon production. According to the petrophysical estimates, the Meyal oil field′s Sakesar and Chorgali Formations are promising reservoirs, and new prospects for drilling wells in the southern and central portions of the eastern portion of the research area are recommended.

A magnetite graphene oxide chitosan (MGOCS) composite microsphere was specifically prepared to efficiently adsorb As(III) from aqueous solutions. The characterization analysis of BET, XRD, VSM, TG, FTIR, XPS, and SEM-EDS was used to identify the characteristics and adsorption mechanism. Batch experiments were carried out to determine the effects of the operational parameters and to evaluate the adsorption kinetic and equilibrium isotherm. The results show that the MGOCS composite microsphere with a particle size of about 1.5 mm can be prepared by a straightforward method of dropping FeCl₂, graphene oxide (GO), and chitosan (CS) mixtures into NaOH solutions and then drying the mixed solutions at 45 °C. The produced MGOCS had a strong thermal stability with a mass loss of 60%) and other metals, showing a great advantage in the treatment of heavy metal-contaminated water.

In mainland China, approximately 86% of $M≥7$ earthquakes have occurred in the block boundary zone, which has been well explained by active block theory. However, a few large earthquakes have occurred within the active block, which provides us with an opportunity to better study the deformation of the Tibetan Plateau. The Litang Fault (LTF) is a strike-slip fault within the Sichuan-Yunnan Active Block and produced the 1948 Litang M7.3 earthquake. We presented the Holocene rupture behavior of the LTF based on detailed field investigations, paleoearthquake trenching, and radiocarbon dating. Specifically, we revealed 13 Holocene paleoearthquake events at four trenching sites and divided these events into 3 rupture cycles at the whole-fault scale. The seismic rupture behavior of the LTF is characterized by recurrent southeastward migration, and since the Holocene, the period of each rupture cycle has decreased rapidly from 8000 years to 500 years. Our results may provide geologic evidence for understanding the intrablock stress patterns and material transfer of the southeastern region of the Tibetan Plateau. The rapidly enhanced fault activity of the LTF since the late Holocene indicates that the LTF may have played an important role in accommodating the deformation of the southeastern region of the Tibetan Plateau.

Ground penetrating radar (GPR) is an effective method that can be applied in pipeline leakage detection. However, when the distribution of the underground medium is complex, it becomes difficult to accurately identify the abnormal leakage area directly from the GPR data profile. In this paper, based on the characteristics of high water content in the abnormal leakage area and according to the relationship between the reflected wave coefficient and the dielectric constant, the electric field component imaging technology of GPR data is proposed. Next, the electromagnetic wave responses of geological models with different dielectric parameters are simulated by finite difference time domain (FDTD). It can be seen from the forward modeling results that the greater the difference is in the dielectric constants of the media on both sides of the interface, the stronger the reflected wave energy will be. Finally, the electric field component imaging technology of GPR data is applied to pipeline leakage detection in an industrial area. The test results show that the abnormal area of pipeline leakage appears as a high‐amplitude area in the electric field component map.

Iron-containing minerals are key factors controlling arsenic (As) transport in groundwater environments. However, few studies have observed the effect of aqueous Fe [Fe(aq)] on As behavior in a water environment. In this study, river sand in the riparian zone was collected for batch experiments to analyze the effect of Fe(aq) on the adsorption of As on river sand, utilizing characterization analyses to identify the reaction mechanism. The results showed that (1) as the concentration of Fe(aq) in the reaction system increased from 0.1 to 20 mg/L, the equilibrium adsorption capacity (Q_e) of river sand for As(III) and As(V) gradually increased. For concentrations of Fe(aq) equal to or greater than 1 mg/L, the Q_e for As(V) exceeds that for As(III), whereas at a Fe(aq) concentration of 0.1 mg/L, the Q_e for As(III) is higher than that for As(V). (2) Compared to the reaction system without added Fe(aq), the adsorption of As(V) onto river sand was inhibited, while the adsorption of As(III) was enhanced under conditions with low concentrations (0.1, 1 mg/L) of Fe(aq). (3) At higher Fe(aq) concentrations (5, 20 mg/L), the adsorption of both As(V) and As(III) by river sand was more effective than in systems without Fe(aq). Characterization tests confirmed this, while Fe(II) reduced As(V), and Fe(aq) adhered to the surface of river sand to form Fe(OH)₃ colloids, thereby facilitating the adsorption of As onto river sand.