A series of quartz granodiorite-granodiorite rock assemblage has been identified in Heiwan area of the Guanzi Town ophiolite mélange. In order to determine the formation mechanism of them, the petrology and whole rock geochemistry of gneissic granodiorite and metamorphic tonalite were conducted, and the zircon U-Pb dating, Lu-Hf isotope, Rb-Sr and Sm-Nd isotope of gneissic granodiorite were conducted. The results show that gneissic granodiorite and metamorphic tonalite have low contents of rare earth and trace elements, and metamorphic tonalite has obvious Eu positive anomaly, and both of them have the characteristics of oceanic plagiogranite. The age of granodiorite obtained is 512.6±2.0 Ma, and the ε_Hf(t) value varies from +8.9 to +13.8, indicating that its magma source area is depleted mantle. The I_Sr value of granodiorite ranges from 0.7046 to 0.7053, and the ε_Nd(t) value ranges from +2.55 to +3.08. Combined with the regional tectonic evolution, this set of ocean plagiogranite was formed by the emplacement of acidic magma formed by partial melting of basaltic rocks in the mantle at low temperature (602.9～707.4 ℃) and low pressure (＜ 0.2 GPa), and was formed in the island arc environment related to the subduction of Shangdan Ocean in the early Middle Cambrian.

This study focuses on the tonalite in the Huashigou in the western section of the Quanji massif, northwestern margin of the Qaidam basin. Based on detailed field investigations, LA-ICP-MS in-situ isotopic dating and elemental analyses were carried out on the primary zircons to explore the evolutionary history of this area during the important tectonic transition period of the Devonian. The CL images of zircons in Huashigou tonalite show that zircon crystals are mostly columnar or irregularly shaped, euhedral to subhedral grains with clear oscillatory zonations. Zircon U-Pb dating yields a weighted average age of 371.1±3.5 Ma, a concordant age of 370.9±1 Ma, and a Th/U ratio of 0.42–0.83. LA-ICP-MS in-situ elemental analysis shows obvious Ce positive anomalies, strong Eu negative anomalies, and relative enrichment in light rare earth elements (LREE) compared to heavy rare earth elements (HREE). Zircon Ti thermometer calculation reveals zircon crystallization temperatures (t_Zr-Ti) ranging from 628 to 722 ℃, indicating a typical magmatic origin. In the Pb-Th diagram, all zircon spots fall within the I-type granite zircon field, representing that the original magma is crust-mantle mixed. Based on the above information, it is inferred that Huashigou tonalite was formed in an extensional environment after the collision, representing a magmatic event caused by mantle upwelling and crustal reworking.

Deep conglomerate reservoirs are developed in the Jiamuhe Formation of the Zhongguai Uplift, Junggar Basin, and are generally characterized by low mud content, abundant zeolite cement, and strong heterogeneity. Based on core observations, thin-section petrography, reservoir physical property analyses, and fluid inclusion tests, a comprehensive investigation was conducted on pore types, diagenetic modifications, and hydrocarbon charging characteristics of the Jiamuhe Formation conglomerates in the Zhongguai Uplift. The results indicate that the formation and evolution of these conglomerate reservoirs are jointly controlled by sedimentary architecture, diagenetic alteration, and hydrocarbon charging processes, which are manifested in three aspects. First, the large clast size and rapid sedimentation rates significantly weakened mechanical compaction during early burial, providing a favorable material basis for the preservation of primary intergranular pores. Second, variations in source-rock lithology and depositional microfacies are key factors controlling reservoir heterogeneity; abundant supply of basic andesitic rocks from the provenance area facilitated extensive precipitation of zeolite cements. Third, the combined contribution from multiple source rocks and the sustained alteration of conglomerates by multi-stage organic acids created favorable reservoir conditions for hydrocarbon accumulation in the full-sag conglomerates of the Jiamuhe Formation. Overall, the formation of conglomerate hydrocarbon reservoirs in the Jiamuhe Formation of the Zhongguai Uplift is interpreted as the result of coupled evolution between near-source, high-energy depositional processes under a fault–sag transition setting and subsequent diagenetic–accumulation processes. The results provide valuable insights for the study and development of deep conglomerate reservoirs in the Junggar Basin.

The undersea gold deposit off northern Sanshandao is a newly discovered super-large gold deposit in the northern Jiaodong Peninsula, located at the northern end of the Sanshandao- Cangshang Fault Zone. A large amount of research work has been carried out on the shallow part of this deposit, but the research on the deep mineralization laws and resource potential is relatively weak. The systematic mineralogical study on pyrite of the deep part of this deposit (at an elevation of –1253 to –1 455 m) is conducted in this paper, to reveal its characteristics of geochemical compositions, explore the genesis of the deposit, evaluate the potential for deep mineral exploration, and provide a scientific basis for regional deep mineral exploration prediction. Based on the theories of genetic mineralogy, this paper conducts an in-depth study on the morphology and compositional characteristics of pyrites from three metallogenic stagesfrom drill coresin this deposit. We obeserved the morphological, particle size, and self-shaping degree characteristics of pyrite and analyzed in-situ trace element composition of pyrites at each stage, using electron probe technology, with a focus on determining the contents of elements such As Fe, S, As, Co, Ni, and Au, and calculating standard parameters such as Co/Ni value and Fe/(S+As) value. The results indicate that the pyrites in this deposit can be divided into three mineralization stages: pyrite sericilization stage (Py1), quartz-pyrite-arsenopyrite stage (Py2), and quartz-polymetallic sulfide stage (Py3). Among them, the pyrites of stage Py2 and Py3 have smaller particle size and poorer hedral degree which have better gold content. he Co/Ni ratio of pyrites in this deposit ranges from 1 to 4, with an average of 3. The pyrites are rich in As and Co, which further indicate that this deposit is of magmatic hydrothermal origin. Collectively, Fe/(S+As) ratios of pyrites, alongside the vertical zonation characteristics of trace element, indicate high prospectivity at depth in the undersea gold deposit off northern Sanshandao.

The water resources of the Ordovician oilfield in the Tarim Basin's Tahe Oilfield are characterized by a high concentration of potassium, lithium, and other trace elements with significant economic value. These resources represent an important strategic asset in the Tarim Basin, alongside oil and gas resources. In this paper, Ordovician oilfield water samples from the Tahe oilfield were collected and analyzed to study its geochemical characteristics and its associated resource distribution pattern. The results demonstrate that the primary cations present in the Ordovician oilfield water of the Tahe Oilfield are Na⁺, Ca²⁺, K⁺, and Mg²⁺, while the primary anions are Cl⁻, SO₄²⁻, HCO³⁻, and NO₃⁻. The mineralization of the oilfield water ranges from 140 to 260 g/L, with an average value of 216.56 g/L, indicating a medium level of mineralization. The oilfield water can be classified as a CaCl₂ type. The characteristic coefficients indicate that the oilfield water undergoes alternating cation adsorption and robust water-rock interactions. It is a solution-filtered oilfield water, exhibiting complete reduction, optimal reservoir confinement, and a notable degree of metamorphism. The ions present in the oilfield water are predominantly derived from rock salt, gypsum, and crumbly clay minerals. The useful components, including K⁺, Li⁺, Br⁻, and Sr²⁺, exist in oilfield water can meet the industrial indicators of comprehensive utilization: the K⁺ content ranging from 556 to 2740 mg/L with an average value of 1781.19 mg/L; the Li⁺ content varying from 2.9 to 18.5 mg/L with an average concentration of 11.16 mg/L; the concentration of Br⁻ ranging from 45 to 323 mg/L with an average concentration of 230.77 mg/L; The concentration of Sr²⁺ ranging from 341 to 605 mg/L with an average of 473.31 mg/L. Conducting research on oilfield water that coexists with oil and gas resources, and comprehensively developing and utilizing the associated resources, is of significant importance for enhancing the resource value of oil and gas fields.

The protection of groundwater environment is a critical foundation for the sustainable utilization of regional water resources. To address the issues of groundwater quality characteristics and human health risks in industrial and agricultural area of Guanzhong plain, this study systematically collected 38 groundwater samples and comprehensively applied mathematical statistics, Piper trilinear diagram, ion ratio analysis, and entropy-weighted water quality index (EWQI) methods to analyze hydrochemical characteristics and assess health risks. The results indicate that: ① The concentration order of cations is Na⁺＞Mg²⁺＞Ca²⁺＞K⁺, while the concentration order of anions is HCO₃⁻＞SO₄²⁻＞Cl⁻＞NO₃⁻, with the main hydrochemical types being Na-Cl-SO₄ and Na-Ca-HCO₃; ② The hydrochemical evolution is dominated by dolomite dissolution and cation exchange, and the distribution of NO₃⁻ concentrations is closely related to industrial activities; ③ EWQI evaluation shows that 92.1% of the samples are suitable for drinking, with poor-quality water mainly concentrated in the industrial agglomeration area in the central-southern part of the region; ④ Human health risk assessment of F⁻ and NO₃⁻ indicates that the non-carcinogenic health risks for different populations follow the order: children＞adult females＞adult males. It is recommended to reduce health risks through targeted measures such as optimizing industrial layout and controlling agricultural non-point source pollution. The research results provide a scientific basis for groundwater pollution prevention and sustainable management in the Loess Tableland region.

Loess is widely distributed in the seasonally frozen regions of China, and its particle composition, pore structure, and engineering properties exhibit significant regional zonation. Under freeze–thaw cycles, the internal pore structure of loess is continuously restructured, thereby affecting its water-holding capacity and the evolution of the soil-water characteristic curve (SWCC). To investigate the regional differences in the water-holding behavior of collapsible loess under freeze–thaw cycles, undisturbed sandy loess from Ningxia, silty loess from Shanxi, and clayey loess from Jingyang were selected. Considering different initial water contents and freeze–thaw cycle numbers, SWCCs were measured using a pressure plate apparatus and fitted with the Fredlund–Xing model. The results show that all SWCCs exhibit a typical S-shaped pattern, and the differences induced by freeze–thaw cycles are mainly concentrated in the main desaturation stage and the high-suction tail. Jingyang samples are the most sensitive to freeze–thaw action and show obvious staged restructuring; Ningxia samples exhibit pronounced moisture-content-dependent divergence; Shanxi samples change more gently overall. The fitted parameters a, b, and c all vary with freeze–thaw conditions, indicating that freeze–thaw cycles not only alter the air-entry-related feature, but also change the slope of the main desaturation section and the residual water-retention behavior in the high-suction range. Regional differences therefore control not only the initial water-holding capacity of loess, but also the restructuring path of its pore system under freeze–thaw disturbance. These findings provide an experimental basis for unsaturated seepage analysis, freeze–thaw degradation assessment, and water-induced hazard prevention in loess engineering in seasonally frozen regions.

Against the background of global climate change and regional water scarcity, in-depth research on the synergistic driving mechanisms of multiple factors controlling vegetation water use in arid and semi-arid regions is urgently required. Existing studies lack sufficient analysis on the synergistic regulation of meteorology-soil water-groundwater in the sap flow process of Salix matsudana Koidz in the Mu Us Sandy Land. Therefore, taking 40-year-old Salix matsudana Koidz in the Mu Us Sandy Land as the research object, this study systematically analyzed the water use strategy of Salix matsudana Koidz under the synergistic effect of meteorological factors and groundwater in the rainy season, and clarified the key paths of meteorological factors regulating the sap flow process of Salix matsudana Koidz, through in-situ continuous monitoring of meteorological elements, groundwater depth, soil moisture content and stem sap flow density, combined with Structural Equation Model and Boosted Regression Tree model. The results show that Salix matsudana Koidz is a deep water-dependent tree species, forming a water use strategy dynamically adjusted with hydro-meteorological conditions in the growing season. It preferentially utilizes deep soil water and groundwater at 250–450 cm, with extremely low utilization efficiency of surface soil water recharged by rainfall. Meteorological factors regulate the sap flow of Salix matsudana Koidz through dual paths of direct driving and indirect synergy. Solar radiation (β=0.71, P<0.001) is the core direct driving factor, relative humidity (β=−0.27, P<0.05) is the key atmospheric constraint factor, and groundwater level exerts a significant positive indirect effect (total effect 0.39) through the hydrological transmission chain of groundwater-deep soil water-vegetation sap flow. The sap flow density of Salix matsudana Koidz peaks when the air temperature is 9.97–21.20℃ and the relative humidity is moderate. This study clarifies the multi-factor coupled driving mechanism of the sap flow process of Salix matsudana Koidz and provides theoretical support for the management of Salix matsudana Koidz forests and ecological restoration projects in the Mu Us Sandy Land.

The disintegration, erosion, and collapse of red-bed mudstone slopes in watershed gullies is prominent in the extreme climate, heightening the risk of disaster chains related to debris flows in these channels. Developing hazard chain-cutting technology in watershed gullies is of great significance for controlling the sediment supply of debris flows. This study selects Tertiary red-bed mudstone from the Xining Basin, and utilizes a self-developed testing apparatus for measuring the disintegration indexes of untreated red-bed mudstone and MICP-treated red-bed mudstone. A list of disintegration tests were conducted to explore the disintegration characteristics and protective effects of MICP-solidified red-bed mudstones under the influence of factors such as temperature, pressure, initial moisture content and curing time. The results indicate that MICP mitigates the disintegration process of red-bed mudstone, which is significantly influenced by initial water content. At low water content, the disintegration process of red-bed mudstone is considerable, which is also accelerated by higher temperatures and pressures. The pressure plays a dual role of mechanical constraint and hydraulic driving in the disintegration process of red bed mudstone. The prolongation of curing time exerts a significant inhibitory effect on the disintegration process of MICP-solidified red-bed mudstones. Specifically, for the specimens cured for 3, 7, and 14 days, the disintegration ratio at initial-stage decreases by an average of 13%, 33%, and 39%, respectively. The disintegration rate drops by an average of 13%, 27%, and 36%, respectively. This is because MICP converts particle contacts from point contact to surface contact, and a calcareous cementation crust forms on the surface of the red-bed mudstone, resulting in a notably lower disintegration ratio and rate during the intense disintegration stage. The findings offer support for ecological protection of red-bed mudstone slopes in weathered gullies of Northwest China.

The Xinjiang (China) to Central Asia region is located north of the Karakum-Tarim Craton and belongs to the Paleo-Asian Ocean tectonic domain, one of the world's three major tectonic domains. Distinguished by its unique geographical setting, this region is rich in mineral resources such as lead, zinc, copper, gold, rare earth, and lithium, and has become an important area for China's international mining cooperation in recent years. Guided by the "multi-island arc-basin system" tectonic model, this paper systematically summarizes the trmporal-spatial distribution, metallogenic setting and deposit types of lead-zinc deposits in the Xinjiang (China) to Central Asia region on the basis of tectonic unit division and carries out the division of three-level metallogenic units. A total of 2 metallogenic provinces are distinguished: Altai(-Xing’an Mongolia) and Kazakhstan-Tianshan; 4 metallogenic belts are Altai, Taerbahatai-West Junggar, Moint-Balkhash-Middle Tianshan and TurgayTalas; and 6 metallogenic subbelts are South Altai, Saryzhal-Zharma, Karasor-Moint-Yili, Bayan Uul- Zheirtau-Middle Tianshan, Karatau and Bukantau-Kyrgyz Mountain. Building on previous research, this paper further analyzes the metallogenic characteristics and typical deposits of each subbelt and discusses regional lead-zinc mineralization in combination with the tectonic evolution of the Paleo-Asian Ocean, aiming to provide a useful references for the comparative study and exploration of lead-zinc deposits in Xinjiang and adjacent overseas areas.