The genesis and tectonic controls on the emplacement of post-collisional granites in the Karakoram Block (KB) in northern Pakistan are unclear due to lack of detailed studies. Zircon U-Pb dating indicates that the Sumayar pluton was emplaced at similar to 9.6 Ma and represented one post-collisional magmatism. The Sumayar granite samples belong to strong peraluminum granites with aluminum saturation indexes of 1.1-1.2. Zircons from the granite exhibit strong negative epsilon(Hf)(t) values mostly of between -30 and -25, indicating a supracrustal source. Whole-rock geochemical data display enrichment in light rare earth elements and large ion lithophile elements, depletion in high field strength elements, and strong negative Eu anomalies. The low CaO/Na2O ratios and high Rb/Sr ratios together with the presence of tourmaline, suggest that the primary magma was formed from dehydrating melting of B-rich metapelites at moderate temperature conditions. In comparison with other post-collisional S-type granites in the KB, two groups were recognized. The first group represented by the Baltoro granite and other granites of ca. 36-15 Ma, is volatile-depleted and B-deficient, and formed from partial melting of greywacke source. The second group represented by the Sumayar granite and other small plutons of 9.6-3.0 Ma, formed from dehydration melting of B-rich metapelitic source. The emplacements of these S-type granitoids are attributed to the episodic partial melting of accretionary wedge rocks and associated crustal anatexes, due to the heat generation during the post-collisional stage at the hanging wall along the collisional boundary between the Kohistan Island Arc and the Asian Plate.

The distribution of Oligo−Miocene magmatic rocks from southern Tibet in space and time yields critical information on the geometry and deformation of the subducted Indian lithosphere which impacts on plateau growth following the India and Eurasia collision. A growing body of geophysical evidence has shown that the subducted Indian lithosphere beneath the Tibetan Plateau has been torn apart. However, the spatiotemporal distribution and cause of the tearing remain enigmatic. Timing of the post-collisional magmatic rocks in southern Tibet exhibits four patterns of decreasing ages; magmatism began earlier in the west and east Himalayan syntaxis and evolved to two age undulations in the central southern Tibet. Seismic images show that regions of slab window (both 90°E and 84°E) and flattened subducted lithosphere (both 86°E and 81°E) are present at depth of 135 km. Correspondingly, increasing mineral crystallization temperatures (absolute value of 50 °C) were recorded in the Oligo−Miocene ultrapotassic-potassic rocks at 90°E and 84°E, while opposing trends were shown by coeval ultrapotassic-potassic rocks at 86°E and 81°E. Besides, the melting depth of the Oligo−Miocene ultrapotassic-potassic primitive melts decreases from nearly 100 km to 70 km between 81°E and 90°E, probably indicating progressive rising of the lithosphere-asthenosphere boundary. Such variations were possibly the results of the focused flow and upwelling of asthenosphere, which advanced rapidly but diachronously through weakened and torn sectors within the overlying Indian slab. The upwellings probably induced diachronously upward bending of the residual Indian slab and its flattening, which accelerated the tearing of the Indian lithosphere during continental subduction.

Presently, various machine learning techniques are commonly used to enhance reservoir properties, including fuzzy logic, neural networks, cluster analysis, self-organizing maps, principal component analysis, genetic algorithms, and more. While each method possesses its own set of strengths and weaknesses, a key challenge faced by most existing techniques is the optimum handling of the diverse, dynamic ranges evident in petrophysical input data. This paper introduces Domain Transfer Analysis (DTA), an advanced method developed from extensive Computational Fluid Dynamics (CFD) research, designed to enhance the integration of diverse petrophysical data types. DTA, distinct from traditional statistical techniques in the petroleum industry, employs a nonlinear partial differential equation solver to more effectively handle input variables that exhibit both logarithmic (e.g., resistivity) and linear (e.g., gamma ray) variations. The study is particularly important as it addresses the critical challenge of optimally handling dynamic ranges in petrophysical input data, which has been a significant limitation of existing methods. The performance of this technique is demonstrated through case studies that examine the prediction of porosity and permeability using a dataset from wells in the Lower Goru sand reservoir, Southern Indus Basin, Pakistan. The comparative analysis of results from different approaches shows the reliability of DTA. The paper concludes with recommendations for optimizing the use of DTA in real-time prediction of porosity and permeability. Furthermore, it shows DTA’s perspective and continuous applications in petrophysical evaluation, including essential parameters such as saturation, total organic carbon (TOC), mineral volumes, and brittleness. These valuable findings can be acquired from data during various phases of the drilling and completion process, enabling a comprehensive evaluation of subsurface characteristics. The present study employed the Domain Transfer Analysis for Optimal Prospectivity Evaluation. The successful application of DTA establishes a solid foundation for reservoir characterization and modeling research. The results show that the Domain Transfer Analysis provides better results than other statistical methods. This approach can be used globally to provide a strong correlation between real and predicted reservoir properties.

The Bubin Cu-Pb polymetallic deposit in Gilgit-Baltistan, Pakistan, is a well-known vein-type ore deposit located in the Kohitan-Ladakh island arc. Due to its significant economic importance as the most important deposit type in the Kohistan-Ladakh island arc, a comprehensive study on its ore genesis, fluids evolution, and genetic classification not only shed new light on our understanding the formation of such polymetallic deposit at a typical intra-oceanic arc, but also of help for the mineral exploration. Here, we present the results from electron probe micro-analyzer, fluid inclusions, Raman spectroscopy, and isotopic studies (O-H-S-Pb) to gain insights into the source of ore-forming fluids and materials, as well as the genetic-type and mechanism of ore precipitation for the Bubin deposit. The mineralization processes were divided into three main stages: Stage I (quartz-pyrite), Stage II (quartz-sulfide), and Stage III (quartz-carbonate). Stage II further comprised two sub-stages: IIa (quartzchalcopyrite-magnetite) and IIb (quartz-galena-fahlore). The ore-forming fluids exhibited high to moderate temperatures (154-540 C-degrees) and varying salinities (0.35-44.30 wt% NaCl) throughout the stages. Stage I fluids displayed critical behavior with high temperature and low salinity, and their isotopic signatures suggested a magmatic origin. Subsequently, the ore-forming fluids gradually evolved from primary magmatic origin to the mixing of meteoric water, as demonstrated by oxygen and hydrogen isotopic values (delta(18)Ofluid = -1.34 to 6.29 %o, delta D = -112.4 to -76.1 %o). The delta S-34 values (-2.92 to 6.52 %o) and Pb isotopic ratios (Pb-208/Pb-204 = 39.06 to 40.93, Pb-207/Pb-204 = 15.72 to 15.99, and Pb-206/Pb-204 = 19.44 to 20.80) suggested a deep magmatic source for the ore-forming fluid, with metals primarily derived from the upper crust, likely associated with the Ladakh Batholith. Fluid boiling and maxing are the dominant mechanisms for ore mineral precipitation. Additionally, the high to moderate temperature and salinity, presence of solid-bearing and vapor rich inclusions, a Co/Ni ratio > 1, the Ni-As-Co diagram, and O-H-S-Pb isotopic evidence collectively support the classification of the Bubin Cu-Pb polymetallic deposit as an intrusion-related porphyry-style magmatic hydrothermal deposit.

The Cu-Sb-Pb polymetallic vein deposit is hosted by metavolcanics rocks of the Gawuch Formation at the Kaldom Gol area of the northwest Kohistan arc terrain in northern Pakistan. The mineralization is closely associated with the dioritic to granodioritic rocks of the Lowari pluton, which was intruded into the Gawuch metavolcanics. Details of ore characterization and processes of ore genesis of this evidently hydrothermal mineralization are not well documented. Integrating petrographic, mineral-chemical and isotopic investigations, this study aims to comprehend the source of hydrothermal fluids, geochemical evolution, mineral inclusions and physicochemical conditions of the Cu-Sb-Pb polymetallic vein deposit in Gawuch metavolcanics in the Kohistan arc terrain in northern Pakistan. The mineralization is distinguished into three types of ore-gangue associations: Type Ia, Type Ib, and Type II. The textural study revealed two pyrite generations: (i) Py1 displaying euhedral to subhedral habits and containing scarce inclusions, and (ii) Py2 occurring as anhedral grains hosting abundant inclusions. Type Ia is characterized by Py1 associated with abundant quartz (Qz) showing comb texture, sericite (Ser), and minor chlorite (Chl). Type Ib comprises Qz + Ser + Chl and Py2, chalcopyrite (Ccp), and magnetite (Mag). Type II is represented by mosaic quartz, rhombic adularia, and bladed calcite, and the ore minerals fahlore and galena. Alteration zones composed of Qz-Ser +/- Chl and Qz-Ser-Chl, surround Type I (a, b) and Type II veins, respectively. Fahlore and galena mostly replace pyrite of Type Ia and chalcopyrite of Type Ib. In addition, malachite, azurite, hematite and covellite occur as secondary (supergene) minerals. The Co/Ni ratios (>1) of Kaldom Gol pyrites suggest that the ore-forming fluids were hydrothermal in origin and Py1 and Py2 solidified at 221-304 degrees C and 225-261 degrees C, respectively. The LA-ICP-MS time-resolved depth profiles confirm the existence of sphalerite, and chalcopyrite inclusions in pyrite (Py1 and Py2) and millerite, bravoite, vaesite, Au-tellurides, native Au and galena inclusions in chalcopyrite and fahlore. Sulfur isotope compositions of pyrites (834S = Py1,-0.58 to +2 %o; 834S = Py2,-0.24 to +2.04 %o) indicate that the ore-forming fluids were derived from magmatic source (s). The mineral assemblage, hydrothermal alterations, textures, temperature and 834S of pyrites suggest that the Cu-Sb-Pb polymetallic mineralization at Kaldom Gol represents an intermediate-sulfidation type of epithermal deposit.

The Juji Nala massive sulfide deposit, hosted in the Chota Pani meta-volcanic rocks of the Kohistan-Ladakh Arc, northern Pakistan, has experienced textural and compositional changes due to metamorphism. This study integrates detailed petrographic and mineral chemical investigations to understand the formation of the original deposit and its subsequent modification due to metamorphism and deformation. The study reveals three distinct types of pyrites: a fine-grained disseminated type (Py1), an anhedral type with cataclastic texture and abundant inclusions of other minerals (Py2a), and an anhedral to euhedral type with scarce micro-inclusions (Py2b). The chalcopyrite is fine to medium-grained and forms intergrowth textures with pyrrhotite, Py2a, and Py2b. Marcasite-pyrite aggregates have replaced pyrrhotite and pyrite, whereas chalcopyrite has remained unaffected. Py1 shows a high Co/Ni ratio (> 1) and low Ni content (avg = 76 ppm), suggesting its crystallization from felsic magma-derived ore-forming fluids at temperatures between 366 and 397 °C. The Juji Nala ores have undergone at least four distinct phases of metamorphism, including the cataclastic Py2a formed under greenschist metamorphism, contact metamorphism (upper greenschist to lower amphibolite facies) due to igneous intrusion, thermal annealing, and late-stage cataclasis and retrograde metamorphism during exhumation. In contrast to pyrite, pyrrhotite and chalcopyrite display ductility, and this explains why the pre-metamorphic features of these two minerals were obliterated during metamorphism. This study provides insights into the formation and modification of the Juji Nala deposit, highlighting the importance of considering metamorphic changes in mineral deposits.

This paper presents petrographic details and geochemical data on gemstone-producing pegmatites and the rocks enclosing them, Sumayar pluton exposed in the vicinity, and chemical composition of a variety of gemstones to elucidate the nature and source of gemstone-forming fluids in the Chumar Bakhoor area of Gilgit-Baltistan, northern Pakistan. The pegmatites occur as patches, pods, lenses, and dykes in calc-silicate rocks and amphibolite belonging to the southern Karakoram Metamorphic Complex (KMC) as well as in the intrusive Sumayar pluton. A close spatial association suggests the possibility of a strong genetic relationship between the Sumayar pluton and the gemstone-hosting granitic pegmatites. Hence, the latter most likely represent pegmatitic phase of a granitic system that in its orthomagmatic stage produced the Sumayar pluton. The pegmatites thus solidified from pockets of volatile-rich melt residues after the granitic magma that solidified as Sumayar pluton. The mineralogical make-up of the pegmatite, the gemstone assemblage, and chemical characteristics of the individual gemstones suggest that the pegmatite-forming melt was highly enriched in Be, B, F, Cl, and H2O, and depleted in Li, REE, and Ta relative to its parent granitic magma. Owing to a strong likelihood of generation by localized partial melting of metapelitic rocks at shallow depth in a post-collisional tectonic setting, the magma parental to the Sumayar pluton had the potential to evolve through the process of differentiation into residues containing gemstone-forming fluids. The calc-silicate rocks, which host the gemstone-producing pegmatites, were formed by isochemical metamorphism of calcareous mudstones rather than metasomatism of carbonate rocks, although they show some mineralogical similarities with skarn-type assemblages. However, the calc-silicate rocks neither played any role in the formation of gemstones nor caused any change in the gemstone chemistry.

The petrogenesis of the Eocene (43–42 Ma) Nb-rich granitoid dykes from the Kohistan–Ladakh island arc provides insights into melting of the down-going Indian continental crust during the Indian-Eurasian continental collision. These Nb-rich granitoids (SiO2 = 53.8–72.3 wt%, Nb = 24.0–44.1 ppm) have high Sr/Y (41.2–76.8) and (La/Yb)N (15.6–36.8) ratios. Their geochemical and Sr–Nd–Hf isotopic compositions are distinct from those of the Kohistan–Ladakh basement (Eurasian continent), but similar to those of coevally metamorphic amphibolites (42–40 Ma) in the Nanga Parbat massif (Indian continent). This implies that the magma of the Nb-rich granitoids would be derived from partial melting of the subducted Indian continental plate. The biotites from the Nb-rich granitoids show high Mg# (up to 61) and Cr2O3 (up to 2.36 wt%) and low TiO2 (0–3.21 wt%). Some samples of the Nb-rich granitoids contain 2–3% phengites with SiO2 ranging from 48.33 to 51.74 wt% and calculated pressure of 1.6–0.6 GPa, indicating initial magma crystallization of the Nb-rich granitoids at high-pressure condition (depth > 55 km). We propose that partial melting of the subducted Indian continental crust occurred when it underthrusted into the Kohistan–Ladakh asthenosphere mantle and the resultant melts upward migrated and significantly modified the overlying lithosphere and the residual Indian continental crust sank into the deep mantle. Both the metasomatized lithospheric mantle and the residual Indian continental crust played a critical role in the formation of the Miocene ultrapotassic rocks in southwestern Tibet.

For decades, the streams and rivers in northern areas of Pakistan are being explored for gold but the source rock for primary gold is yet to be located. Recent geological surveys have identified several areas for follow-up study for Cu-Au mineralization in Chitral and Gilgit-Baltistan regions. The rocks exposed at various localities are variably altered and/ or mineralized and intensely deformed, which mostly include diorite, granodiorite, greenschists, limestones and undeformed volcanic rocks and granitoids of the Kohistan island arc. The results of petrographic and X-ray diffraction (XRD) analyses of a variety of representative rock samples from a number sites have revealed that mineralization in the Chitral and Gilgit-Baltistan regions is dominantly in the form of pyrite, tetrahedrite, chalcopyrite and galena with subordinate amounts of magnetite, malachite and azurite. The associated/ gangue minerals include albite, quartz, actinolite, biotite, chlorite, epidote, calcite, garnet, illite and titanite (sphene). Diffraction patterns of glycolated samples did not show the existence of swelling clay (e.g., smectite). Sericitic, chloritic and carbonatic alterations have been observed in the studied altered rocks. Mass balance calculations indicate that most of the sulfide-bearing samples are enriched in Cu, Au, Sb, As and Pb and depleted in the rest of the metals reflecting differences in elements mobility during the ore-forming processes. Some of the mineralized rocks especially limestone have experienced a significant volume change due to mobilization of some of the major element oxides e.g. CaO, Fe2O3, SiO2 and ore-forming components e.g. Cu and Pb. The mineralization is of epithermal type in most of the investigated sites, however a few areas show ore formation though orogenic processes and very rarely the ore deposit displays features of the volcanogenic massive sulfide type. Some of the areas are quite promising with respect to their ore element contents and the highly mineralized zones lie in close proximity to major structures in the region. Besides, results from the current study indicate that the mineralization shows close spatial association and hence a strong genetic link with strike slip faults especially where they bend and merge together.

Two rare polyketides, named as janthinopolyenemycins A (1) and B (2), were isolated from a co-culture of two marine-sourced bacteria Janthinobacterium spp. ZZ145 and ZZ148. Their structures were established by a combination of extensive NMR spectroscopic analyses, HRESIMS data, and ECD calculation. Both janthinopolyenemycins A and B showed activity in inhibiting the growth of Candida albicans with a MIC value of 15.61 mu g/mL and a MBC value of 31.25 mu g/mL. (C) 2018 Elsevier Ltd. All rights reserved.

The southeast Hazara forms a part of Himalayan fold and thrust belt of Pakistan. The study area is covered by Mesozoic-Cenozoic age rocks that have undergone severe deformation and is characterized by the formation of complex fold and thrust assemblages. The structures include northwest and southeast verging thrust systems with associated folds. Two deformational events separate the structures in the area. The structures in the northwestern quadrant display southeast facing direction whereas the southeastern quadrant is dominated by structures that dip towards southeast. The general trend of the structures is northeastsouthwest and that attributes to the northwest-southeast contractile deformation. The trend of the structures depicts that stresses were directed from northwest. The folds are found to be tight to overturned and the cores of the folds are usually occupied by competent Samana Suk Formation. The organic rich horizons were observedin the eld within the Formation, the TOC of which was calculated as 0.28%. Microfacies analysis reveals well sorted and well-rounded ooidal-peloidal grainstones and packstones as well as dolomitized and fractured wackestones and mudstones. The diagenetic signatures include fracturing and dolomitization depicting its source and reservoir quality for a hydrocarbon prospect.