ABSTRACT To address the challenges of self‐supporting backfill stability and surrounding rock control in multi‐step mining, this study proposes an innovative upward segmented backfilling approach tailored to the lithological characteristics of gold deposits. The method aims to optimise backfill structural integrity, mitigate ground instability risks, and ensure safe mining operations under complex multi‐stage extraction conditions. The method involved a combination of theoretical analysis, experimental research, and numerical simulations to investigate the self‐supporting and stability of multi‐step backfilling and explore the strength and structural characteristics of the backfill design. The results indicated that the determined backfill ratios were as follows: graded tailings (concentration 74%) at a 1:4 ratio, with an R 28 strength of 2.453 MPa; full tailings (concentration 64%) at a 1:4 ratio, with an R 28 strength of 1.75 MPa. The length and height of the backfill have a positive correlation with the self‐supporting strength of the backfill, while the width of the backfill has a negative correlation. For thin vein mining, priority should be given to the backfill height. It is recommended that the segmented height of thin vein mining should not exceed 20 m to improve the self‐supporting nature of the backfill.

ABSTRACT Triaxial loading and unloading tests on sandstone samples were conducted under various stress paths to investigate the mechanical properties and energy evolution during rock deformation. The results show a positive correlation between the peak strength and peak strain of sandstone and confining pressure. Both the elastic modulus and Poisson's ratio also increase with confining pressure. Notably, the peak strength and peak strain are minimised under conditions of constant axial stress (CAS) while unloading confining pressure (UCP). For different stress paths, sandstone primarily stores elastic energy with minimal energy dissipation during the initial loading stage, while the proportion of dissipated energy increases with rising confining pressure. During the weakening stage, the threshold value gradually decreases to below 80%, leading to a gradual transformation from rock brittleness to ductility. Under conventional triaxial compression (CTC), rock failure predominantly occurs through shear failure. In the involving increasing axial stress (IAS) while UCP test, a complex tensile‐shear mixed failure mode is observed, whereas no main shear plane forms under CAS‐UCP. Sandstone predominantly undergoes tensile failure under cyclic loading and unloading (CLU). Additionally, an increased loading rate inhibits the initiation and propagation of internal cracks in sandstone at the early stage but promotes damage during the damage development and accelerated development stages. Therefore, hydraulic fracturing design must concurrently account for both tensile and shear fracture mechanisms, with precision optimisation of operational parameters to maximise fracture network complexity.

ABSTRACT The South Altyn Tagh (SAT) is renowned for hosting high‐pressure to ultrahigh‐pressure (HP–UHP) rocks indicative of continental deep subduction. Nevertheless, its geodynamic evolution remains enigmatic due to uncertainty regarding protolith origins and the intricate relationships between HP–UHP rocks and their coeval, unmetamorphosed or low‐grade metamorphic counterparts. This study presents novel LA–ICP–MS zircon U–Pb ages, zircon Lu–Hf isotopic compositions and whole‐rock geochemical analyses of both HP–UHP felsic gneiss and unmetamorphosed to low‐grade metamorphic Neoproterozoic granite samples from the SAT, northwestern China. Our findings indicate that both felsic gneiss and granite samples share protolith ages ranging from 920 to 898 Ma, displaying a high K 2 O content and low CaO and Na 2 O contents, characteristic of S‐type granites. The presence of inherited zircons with ages of 1.79–1.40 Ga, along with ε Hf ( t ) values of –5.32 to +4.03 and T DM2 ages of 2.00–1.54 Ga for ~900 Ma zircons, suggests that both felsic gneisses and granite samples originated from the partial melting of Mesoproterozoic metasedimentary rocks. Zircon grains of felsic gneiss samples exhibit a metamorphic age cluster at 505–498 Ma, consistent with the ~500 Ma continental deep subduction event in the SAT. Conversely, granite samples lack ~500 Ma metamorphic age records; a few granite samples record a younger anatectic age cluster at 455–452 Ma, indicating the influence of a ~450 Ma post‐collisional extension event in the SAT. Integrating petrological and geochemical investigations of both felsic gneisses and Neoproterozoic granite samples in the SAT and adjacent orogens, we propose that: (1) both the felsic gneisses and Neoproterozoic granites in the region formed during the late syn‐collision to extensional collapse of the Rodinia supercontinent, (2) the rifting of Rodinia (860–623 Ma) resulted in the development of the Proto‐Tethys ocean and the isolation of granite plutons along margins of different continental blocks, (3) the early‐Palaeozoic continental collision (~500 Ma) subjected the Neoproterozoic granite in the subduction plate to continental deep subduction and led to the coexistence of HP–UHP felsic gneiss and non‐subducted Neoproterozoic granite in the SAT after the exhumation process. These results demonstrate that HP–UHP felsic gneisses and Neoproterozoic granites preserve a complex tectono‐metamorphic history spanning Rodinia's fragmentation, the Proto‐Tethys ocean's evolution and the Early Palaeozoic orogeny.

ABSTRACT In this study, mineralogy and modal components of sandstones from the Neogene Surma and Tipam Groups in the Assam‐Arakan Basin were analysed to understand their provenance, tectonic setting, and palaeoclimate. Petrographic composition and heavy mineral assemblages suggest that most of the sandstones have been supplied by a mixed provenance. However, an increase in the metamorphic detrital input has been observed in the overlying sandstones of the Tipam Group, suggesting more contribution from a metamorphic source. Modal analysis of the Neogene sandstones also suggests a mixed provenance where most of the sandstones were supplied from a recycled orogeny comprising collision suture, fold‐thrust belt, arc orogen, and subduction complex sources. With changing tectonics and the upliftment of the Shillong Plateau and/or Karbi Anglong massif, the supply of sediments from the Indian Craton and Eastern Himalayas into the Assam‐Arakan Basin decreased. Though the supply of sediments from the Eastern Himalayas continued until the end of the deposition of the Tipam Group, the detrital input from the uplifted Naga Ophiolites and Naga Metamorphics had increased significantly. Palaeoclimate analysis for the sandstones reflects a semi‐humid climate during the deposition of both marine Surma and fluvial Tipam Groups, which coincides with the Miocene Climatic Optimum.

ABSTRACT Climate change and environmental degradation have become a prominent part of the worldwide discourse. In the age of global warming, innovation (proxied by patents) is frequently seen as a way to lessen environmental pollution. This study examines the impact of innovation on CO 2 emissions while controlling for factors such as renewable energy use, education, financial development, and economic growth in Saudi Arabia. The study uniquely combines innovation, human capital, financial development, and renewable energy within a nonlinear quantile framework to reveal Saudi‐specific dynamics of the innovation–environment relationship. It utilizes quantile‐based “multiple threshold nonlinear autoregressive distributed lag (MTNARDL)” estimation employing data from 1990 to 2022. It also applies the NARDL approach concurrently for comparative assessment. Moreover, cointegrating regression is employed to cross‐check the primary MTNARDL outcomes. The findings reveal that patents minimize environmental pollution in their lower quantiles but intensify it in their fourth quantile. Energy transition and financial developments improve environmental quality, but economic growth deteriorates it, and human capital remains insignificant. The MTNARDL estimation appears robust, as authenticated by the FMOLS estimates. The findings have significant implications for policymakers, who should prioritize rationalizing patent systems, promoting renewable energy use, enhancing financial development, and adopting green production technologies to ensure environmental sustainability.

ABSTRACT In this study, high‐resolution Gravity and Magnetics (G‐M) surveys were deployed to target concealed ultramafic (UM) host rocks with Chromitite‐bearing layers. These surveys were conducted in the Kathpal region, Sukinda valley, Orissa, India, on profile and grid modes with a station interval of 5 m. The acquired G‐M data is processed to delineate denser bodies of > 3.8 g/cc 3 , and is corroborated with the borehole data and lithological units. The integration of geological and geophysical data from high‐precision G‐M measurements was effective in deciphering the denser materials of chromite‐bearing ultramafic lithounits. Spectral analysis of G‐M data confirms two layers at a depth of 20 m, representing serpentinite ± chromite, and at 70 m, with ultrabasic rock units in corroboration with borehole lithology. The 2D inversion model corroborates the concealed denser rocks with chromite mineralisation and two layers of chromite with a maximum thickness of 4 and 13 m, respectively. The 3D inversion model shows expressions of denser rocks with chromite mineralisation having a thickness of 30 m.

ABSTRACTNew material of Listriodon pentapotamiae was recovered from Dhok Bun Ameer Khatoon, Chinji Formation of Siwaliks, Pakistan. This locality represents the Lower Chinji Formation with an estimated age of 14.2–13.2 Ma. The studied material includes an upper second incisor, upper second molars, and a well‐preserved, complete mandibular fragment with c‐m3, which is very elongated. These teeth are smaller compared to other genera of the family Suidae. I2 is small and chisel shaped, while in all molars, prominent lophs are present. These new findings advanced our understanding of the morphology of Listriodon within the Lower Siwaliks of Pakistan.

ABSTRACTThe gold (Au) metallogenic belt in the northern Great Xing'an Range is characterised by the wide occurrence of the Early Cretaceous orogenic and epithermal Au deposits. Systematic studies of the Pangkaimen Au–Ag deposit could shed new light on the Early Cretaceous Au metallogenesis in this area. The purpose of this study is to determine the ages of mineralisation, reveal the source, and evolution of the ore‐forming fluid system, and discuss the source of the ore‐forming materials of the deposit. The ore‐bearing pyrite Rb–Sr dating yielded an age of 118 ± 2 Ma. The fluid inclusion studies showed that the ore was precipitated from the hydrothermal fluids within a temperature and salinity range of 232°C–345°C and 2.1–8.7 wt.% equivalent, respectively. H–O isotopic compositions indicate the involvement of both magmatic and meteoric water in the hydrothermal system with fluid mixing which are the major mechanisms behind mineral precipitation. The pyrite and sphalerite S (δ34SV–CDT values: −0.3‰ to 4.33‰) and Pb (206Pb/204Pb ratios of 18.334–18.372; 207Pb/204Pb ratios of 15.550–15.566) isotopic compositions suggest that the ore‐forming materials were derived from the basic‐intermediate volcanic rocks of the Lower Cretaceous Longjiang Formation.

Adolf Vitaliiovych Alieksieienko – Candidate of Geological and Mineralogical Sciences, Associate Professor of the Department of General Geology of the Geological Faculty of Ivan Franko Lviv State University, permanent head, for a long time, of the Central Asian expedition of the research sector of the university, a tectonist known in geological circles on geology of Ukraine and Central Asia. For more than two decades, Adolf Vitaliiovych conducted field research on the Southern Tien Shan in a group of geologists under the scientific supervision of a great connoisseur of the region, Professor D.P. Rezvoy. For the first time in the framework of structural and formation work in the region, A.V. Alieksieienko studied, described in detail the material and tectonic structure of the zone of the South Ferghana deep fault, emphasized its metallogenic significance and considered its Paleozoic geological history as one of the key lineaments of the Tien Shan. Further studies of Turkestan-Alai allowed A.V. Alieksieienko and his colleagues to compile the first structural and formational map of the territory on a scale of 1:200,000, for which criteria for tectonic zoning, the legend of formations were developed and the wide development of deep faults was shown. Further work was related to the study of the concentric (ovoid) type of structures that were found in the southwestern wing of the Talas-Ferghana fault. Studies took place synchronously with the development of ideas that the deep faults of the Southern Tien Shan make up the links of the global Trans-Eurasian lineament. Ovoid structures are initiated by intersections of deep faults of sublatitudinal extension with systems of diagonal Anti-Tianshan disjunctiva. The teaching activity of A.V. Alieksieienko is closely connected with scientific work. Simultaneously with the teaching of theoretical material, he conducts practical, laboratory and seminar classes, training practice for first-year students, carries out preparatory mentoring of senior students before industrial practices, develops training and work programs, writes methodological instructions, prepares applications for new sets of educational geological and regional maps, aero- and space photographs. The rector of the university repeatedly awards associate professor A.V. Alieksieienko with thanks for significant achievements in scientific and pedagogical activity. The Faculty of Geology remembers Adolf Vitaliiovych Alieksieienko as a talented tectonist, teacher, mentor, true citizen, and extraordinary person who actively contributed to the establishment and formation of the widely known Lviv Geological School.

ABSTRACT Volcanic carbonatitic breccia is the most voluminous carbonatite formation found in the Amba Dongar Complex (ADC). These breccias are present in both the inner ring dyke as well as the northwestern region of Mongra‐Padvani, referred to as the outer breccia. This study presents the mineral chemistry of apatite along with whole‐rock geochemistry of the matrix from volcanic carbonatitic breccia of the Padvani region from ADC. The breccias are matrix‐supported with few carbonatitic clasts of ADC. Apatites are found in the groundmass and display a morphology and chemistry that are distinct compared to apatites from the coherent carbonatites of the ADC, and have significantly larger concentrations of rare earth elements. The trace element concentration of the carbonatitic matrix closely resembles that of ADC, with anomalously high Nb (290–960 ppm) linked to a significant presence of pyrochlore supergroup minerals. REE‐bearing phases include monazite and pyrochlore group of minerals with minor parisite‐Ce. The samples also exhibit high (La/Yb) CN values (~42), and moderate (La/Sm) CN values (~7), with similar REE patterns compared to the ADC carbonatites. The integrated study of petrography, whole‐rock geochemistry, and mineral chemistry suggests that the Mongra‐Padvani region is a secondary eruption centre in the northwestern region of ADC. An emplacement model is presented for the origin of the outer breccia. In addition, the present study highlights the economic relevance of carbonatitic breccia in the ADC, emphasising their potential as hosts for REE mineralisation. The significant concentration levels observed in these rocks suggest promising avenues for mining endeavours.