Taphonomy and paleoecology (biological behavior) of the Early Cretaceous fish fossils are poorly described. This study reports for the first time a detailed taphonomical and paleoecological study on Lycoptera in the Mesozoic strata of western Liaoning Province, NE China. The XRD analysis shows that gismondine is the dominant clay minerals that could have contributed to the preservation of Lycoptera fossils and microbial mat fragments in the fossil-bearing horizon. Gismondine may have formed under volcanism-related hydrothermal regime that was transformed from crystal and lithic fragments. The μ-XRF imaging analysis shows a dominant chemical composition of Al, Si, P, S, Rh, K, Ca, Ti, C, Cr, Mn, Fe, Ni, among which P, Ca, C and S are enriched in the fish skeleton in comparison to the matrix. This suggests a dominant apatite composition for the fish skeleton. Hydrothermal influence did not smear off these organic signals probably because of protection of gismondine. The coexistance of C and S with Ni is assumed to represent recovered primary productivity following volcanic explosions and toxic gas emissions. The head of juvenile fish stays close to the body of adult fish. Pending further discoveries, such phenomenon is interpreted to suggest that adult fish actively protected juvenile fish in the presence of environmental pressures such as anoxia and deterioration of water quality induced by volcanism. Ocean acidification and hypoxia in association with volcanism created a harmful environment causing mass extinction of fish. The adult Lycoptera protected their juveniles by its body at the moment before death. Such biological behavior will be increasingly reported given the wide occurrence of Lycoptera in Mesozoic strata.

Two hundred and fifty single first-order Arrhenius reactions are simulated to generate S2 pyrograms at three heating rates 25, 15, and 5 ℃·min^-1. The activation energy (E) and pre-exponential factor (A) of the reactions simulated follow a long-established trend of those variable values displayed by shales and kerogens. The characteristics of the transformation fraction (TF) profiles (product generation window temperatures) of the simulated single reactions are compared to the TF profiles of recorded shale pyrograms generated by multiple reactions with different E-A values lying near the defined E-A trend. Important similarities and differences are observed between the TF profile values of the two datasets. The similarities support the spread of E-A values involved in shale pyrogram best fits. The differences are most likely explained by the complexity of the multiple kerogen first-order and second-order reactions contributing to the recorded shale pyrograms versus the simplicity and crispness of the single first-order reactions simulated. The results also justify the validity of using the previously described “variable E-A pyrogram-fitting method” of multi-heating-rate shale pyrograms enabling optimizers to choose multiple reactions from an unlimited range of E-A values. In contrast, further doubt is cast on the validity of the constant-A pyrogram-fitting method used by the Easy%Ro technique, in that a distribution of reactions with a single A value is unlikely to represent the complex variety of kerogen macerals observed in shale formations. TF profiles generated by the variable E-A pyrogram-fitting method lie close to the established E-A trend and are likely to provide more realistic TF generation window temperatures than TF profiles generated by the constant-A pyrogram-fitting method.

Anatolia is the global archetype of tectonic escape, as witnessed by the devastating 2023 Kahramanmaraş Earthquake sequence, and the 2020 Samos Earthquake, which show different kinematics related to the framework of the escape tectonics. Global Positioning System (GPS) motions of the wedge-shaped plate differ regionally from northwestwards to southwestwards (from east to west). Anatolia was extruded westward from the Arabian-Eurasian collision along the North and East Anatolian fault systems, rotating counterclockwise into the oceanic free-faces of the Mediterranean and Aegean, with dramatic extension of western Anatolia in traditional interpretations. However, which is the dominant mechanism for this change in kinematics, extrusion related to the Arabia/Eurasia collision or rollback of the African slab beneath western Anatolia is still unclear. To assess the dominant driving mechanisms across Anatolia, we analyze recent GPS velocity datasets, and decomposed them into N-S and E-W components, revealing that westward motion is essentially constant across the whole plate and consistent with the slip rates of the North and East Anatolia fault zones, while southward components increase dramatically in the transition area between central and western Anatolia, where a slab tear is suggested. This phenomenon is related to different tectonic driving mechanisms. The Arabia-Eurasia collision drives the Anatolian Plate uniformly westwards while western Anatolia is progressively more affected by the southward retreating African subducting slab west of the Aegean/Cypriot slab tear, which significantly increases the southward component of the velocity field and causes the apparent curve of the whole modern velocity field. The 2020 and 2023 earthquake focal mechanisms also confirm that the northward colliding Arabian Plate forced Anatolia to the west, and the retreating African slab is pulling the upper plate of western Anatolian apart in extension. We propose that the Anatolian Plate is moving westwards as one plate with an additional component of extension in its west caused by the local driving mechanism, slab rollback (with the boundary above the slab tear around Isparta), rather than separate microplates or a near-pole spin of the entire Anatolian Plate, and the collision-related extrusion is the dominant mechanism of tectonic escape.

Strain localization processes in the continental crust generate faults and ductile shear zones over a broad range of scales affecting the long-term lithosphere deformation and the mechanical response of faults during the seismic cycle. Seismic anisotropy originated within the continental crust can be applied to deduce the kinematics and structures within orogens and is widely attributed to regionally aligned minerals, e.g., hornblende. However, naturally deformed rocks commonly show various structural layers (e.g., strain localization layers). It is necessary to reveal how both varying amphibole contents and fabrics in the structural layers of strain localization impact seismic property and its interpretations in terms of deformation. We present microstructures, petrofabrics, and calculate seismic properties of deformed amphibolite with the microstructures ranging from mylonite to ultramylonite. The transition from mylonite to ultramylonite is accompanied by a slight decrease of amphibole grain size, a disintegration of amphibole and plagioclase aggregates, and amphibole aspect ratio increase (from 1.68 to 2.23), concomitant with the precipitation of feldspar and/or quartz between amphibole grains. The intensities of amphibole crystallographic preferred orientations (CPOs) show a progressively increasing trend from mylonitic layers to homogeneous ultramylonitic layers, as indicated by the J_Am index increasing from 1.9–4.0 for the mylonitic layers and 4.0–4.8 for the transition layer, to 5.1–6.9 for the ultramylonitic layers. The CPO patterns are nearly random for plagioclase and quartz. Polycrystalline amphibole aggregates in the amphibolitic mylonite deform by diffusion, mechanical rotation, and weak dislocation creep, and develop CPOs collectively. The polymineralic matrix (such as quartz and plagioclase) of the mylonite and the ultramylonite deform dominantly by dissolution-precipitation, combined with weak dislocation creep. The mean P and S wave velocities are estimated to be 6.3 and 3.5 km/s, respectively, for three layers of the mylonitic amphibolite. The respective maximum P and S anisotropies are 1.5%–6.4% and 1.8%–4.5% for the mylonite layers of the mylonitic amphibolite, and 6.0%–6.9% and 4.5%–5.0% for the transition layers; but for the ultramylonite layers, these values increase significantly to 8.0%–9.1% and 5.1%–6.0%, respectively. Furthermore, increasing strain (strain localization) generates significant variations in the geometry of the seismic anisotropy. This effect, coupled with the geographical orientations of structures in the Hengshan-Wutai-Fuping complex terrains, can generate substantial variations in the orientation and magnitude of seismic anisotropy for the continental crust as measured by the existing North China Geoscience Transect. Thickened amphibolitic layers by extensively folding or thrusting in the middle crust can explain the strong shear wave splitting and the tectonic boundary parallel fast shear wave polarization beneath the Hengshan-Wutai-Fuping complex terrains. Therefore, signals of seismic anisotropy varying with depth in the deforming continent crust need not deduce depth-varying kinematics or/and tectonic decoupling.

The Changning-Menglian suture zone is a critical tectonic belt pivotal to the evolution of the Paleo-Tethys. The Wenquan Formation, characterized as turbidite deposited on the western side of the Changning-Menglian suture zone as well as the eastern edge of the Baoshan Block. Analysis of detrital zircons from the Wenquan Formation reveals two significant age peaks approximately at 440 and 980 Ma, with additional age populations around 600, 780, and 2 500 Ma. The major age peak at about 440 Ma is come from the andesitic-dominant volcanic arc within the Lancang Block and the western Simao Block, corroborated by the presence of andesite fragments in thin section studies. Meanwhile, the zircons that form the secondary age peak at ~980 Ma and other older age groups probably originate from the Baoshan Block. Deposited on the western side of the Paleo-Tethyan ophiolites, the Wenquan Formation received detrital materials from the continental margin on the opposite side. Thus, the main Paleo-Tethyan Ocean basin was not sufficiently broad enough to cut off the transference of detrital materials. It was a relatively narrow basin in the Early Devonian.

The Mongol-Okhotsk Ocean, which has been closing gradually from the west to the east beginning since the Late Paleozoic, was an important part of the Central Asian Orogenic Belt. It influenced the tectonic framework of Northeast Asia in the Mesozoic, especially the Late Mesozoic arc-basin system that is widely distributed in the Great Xing'an Range. However, the manner in which the Mongol-Okhotsk Ocean affected the sedimentary basin development remains poorly understood. To address this issue, we conducted U-Pb dating of detrital zircon deposited sedimentary basins of the central Great Xing'an Range. By examining the possible provenances of the detrital zircon and the structural controls of the basins, we found that a key sedimentary unit was deposited around Late Jurassic–Early Cretaceous. Its provenance was a felsic source in a back-arc setting of an active continental margin. The findings also suggest the existence of a unified geodynamic setting that affected the coeval development of basins in the northern Great Xing'an Range and the Yanshan fold-thrust belt along the northern margin of North China Craton. This research helps to better understand the complex tectonic processes which shaped the Northeast Asia during the Late Mesozoic.

In situ zircon U-Pb geochronological and Lu-Hf isotope studies of detrital zircons from Late Mesoproterozoic to Early Neoproterozoic sedimentary units on the southwestern margin of the Yangtze Block have important implications for the tectonic evolution of the Yangtze Block. The Huili Group contains zircons whose ages are mainly Late Archean to Mesoproterozoic (2 650–2 450, 2 100– 1 800, and 1 350–1 150 Ma). The Dengxiangying Group has one major age population of 1 900–1 600 Ma, and two subordinate age populations of 1 350–1 100 and 2 300–2 000 Ma. Yanbian Group sedimentary rocks have a zircon age population mainly in the range of 970–850 Ma, contemporaneous with the ages of widespread arc-related magmatism in the western Yangtze Block. Combining these results with previous work, the Huili and Dengxiangying groups were most likely deposited during ca. 1 160 to 1 000 Ma in an intra-continental rift basin setting, while the Yanbian Group accumulated during > 920 to 782 Ma in a back-arc basin setting at the southwestern margin of the Yangtze Block. In addition, all these results further suggest a tectonic transition from a continental rift basin to a convergent environment at the southwestern margin of the Yangtze Block at 1 000–970 Ma.

The deformation mechanisms of the Tianshan orogenic belt (TOB) are one of the most important unresolved issues in the collision of the Indian and Eurasian plates. To better understand the lithospheric deformation of the eastern Tianshan orogenic belt, we combined the S-wave tomography and gravity data to develop a three-dimensional (3D) density model of the crust and upper mantle beneath the eastern Tianshan area. Results show that the crust of the eastern Tianshan is mainly characterized by positive density anomalies, revealing widespread subduction-related magmatism during the Paleozoic. We however have also observed extensive low-density anomalies beneath the eastern Tianshan at depths deeper than ~100 km, which is likely linked to a relatively hot mantle. The most fundamental differences of the lithosphere within the eastern Tianshan occur in the uppermost mantle. The uppermost mantle layers in the Bogda Shan and Harlik Shan are relatively dense. This is likely associated with an eclogite body in the uppermost mantle. The most significant negative anomaly of the uppermost mantle is however found in the Jueluotage tectonic belt and the central Tianshan Block and is possibly associated with depleted mantle material. We suggest that these differences related to compositional changes may control the strength of the lithospheric mantle and have affected the uplift of the northern and southern segments of the eastern Tianshan after the Permian.

Crossing conjugate normal faults (CCNFs) are extensively developed in many hydrocarbon-producing basins, generally existing in the form of incomplete CCNFs. Nevertheless, the effect of the non-conjugate zone of the CCNFs on the conjugate relay zone post late tectonic action has not been previously studied. We use 3D elastic-plastic modeling to investigate the influence of incomplete (i.e., partially intersecting) CCNFs on the pattern of deformation of strata in the intersection region. A series of model simulations were performed to examine the effects of horizontal tectonic extension, fault size, and fault depth on the deformation of conjugate relay zones of incomplete CCNFs. Our analyses yielded the following results. (1) The model of incomplete conjugation predicts a convex-up style of deformation in the conjugate graben region superimposed on overall subsidence under applied horizontal tectonic extension. (2) The degree of convex-up deformation of the conjugate graben depends on the influence of the non-conjugate zone on the conjugate relay zone, which varies with the amount of horizontal tectonic extension, fault size, and fault burial depth. (3) Our results indicate that incomplete CCNFs can form convex-up deformation, similar to that in the Nanpu Sag area and provide a sound understanding of hydrocarbon migration and accumulation.

The Sangong Cu-Ni sulfide mineralized mafic-ultramafic intrusion is located on the southern margin of the Bogeda-Harlik belt, eastern Tianshan, China. The intrusion is a well-differentiated complex and is comprised of leucogabbro, gabbro, olivine gabbro, Pl-bearing peridotite, and Pl-bearing pyroxenite. The Pl-bearing pyroxenite hosts both irregularly disseminated sulfide and round droplet sulfide. The intrusive rocks have a wide range of SiO₂(42.1 wt.%–50.48 wt.%) and MgO (6.21 wt.%–22.11 wt.%), and are enriched in light rare earth elements (LREE), large-ion lithophile elements (LILE; e.g., Rb, Ba, Sr, and Pb), and palladium platinum group elements (PPGE) but depleted in high-field-strength elements (HFSE; e.g., Nb, Ta, and Ti) and iridium PGEs (IPGE). These geochemical characteristics indicate that the Sangong mafic-ultramafic intrusion was derived from high degree of partial melting of depleted mantle and interacted with subduction-related material. The low Pd/Ir (3.21–27.44) but high Ni/Cu (1.64–24.16) ratios, combined with the olivine crystals with low Fo (60.88–78.65) and Ni (54.99 ppm–1 688.87 ppm) concentrations suggest that the parental magma of the Sangong intrusion were likely high MgO basaltic in composition that experienced extensive evolution prior emplacement. The Ce/Pb ratios (5.8–13.6) and Nb/U ratios (11.6–30.3) of the intrusive rocks all range between MORB and crustal values, the Nb/Yb and Th/Yb values are close to the lower crust values, together with the low Se/S ratios [(17-100) × 10^-6)] suggest that the magma experienced assimilation not only in mantle source but also in conduit, but the degree of crustal contamination is limited. The Cu/Pd ratios of the rocks range from 3.9 × 10⁴to 10.8 × 10⁴, and the Cu/Zr ratios of Pl-bearing pyroxenite in the Sangong intrusion are > 1, combined with the presence of sulfide droplets in the Pl-bearing pyroxenite, indicating the parental magma experienced sulfide saturation and the economical ore bodies may present in the depth of the intrusion. Furthermore, given the discovery of the Baixintan and Yueyawan deposits, we propose the Dananhu-Harlik belt as an essential prospecting target for Cu-Ni mineralization in North Xinjiang.

The Hardawu granites in the eastern segment of the ultrahigh-pressure metamorphic belt, the northern Qaidam Basin, were studied by whole-rock major and trace elements and in-situ zircon U-Pb geochronology and Hf isotopes to discuss the petrogenesis and tectonic evolution. Geochronological results show that the granites have a crystallization age of 401 ± 3 Ma, suggesting that they were formed in the Early Devonian. The granites have SiO₂ contents of 75.32 wt.%–76.05 wt.%, total alkali contents of 8.23 wt.%–8.36 wt.%, and K₂O/Na₂O ratios of 1.62–1.91. They were rich in K₂O, poor in TiO₂, MnO, MgO, and P₂O₅, and have A/CNK values of 1.05–1.07, Rittmann index δ values of 2.05–2.14, and differentiation index (DI) values of 92.85–94.18. They are high potassium calc-alkaline, weak-peraluminum, and highly differentiated I-type granites. The granites also show enrichment of large ion lithophile elements (LILE) such as Rb, Ba, and Th, and depletion of high field strength elements (HFSE) such as Nb, Ta, and Ti. The total REE concentrations range from 169 ppm to 232 ppm, with enrichments of light rare earth elements and negative Eu anomalies (δEu = 0.39–0.55). The zircon ε_Hf(t) values range from -0.65 to -2.29, and the two-stage model ages (t_DM2) changed within a small range of 1.44 to 1.54 Ga, indicating that the magma of the Hardawu granites was originated from the partial melting of Mesoproterozoic lower crustal materials. Combined with previous studies, we suggest that the Hardawu granites were formed in the extensional tectonic setting after the collision between the Qaidam Block and the central and southern Qilian Block in the Early Devonian.

The Mesozoic intrusions of the Jiaodong Peninsula, eastern China, host giant gold deposits. Understanding the genesis of these deposits requires the determination of the source of the parental auriferous fluid and the timing of gold mineralization, which are strongly influenced by the cooling/uplift histories of the hosting intrusions. We performed an integrated U-Pb geochronology study on both zircon and apatite from four major magmatic episodes of the Jiaodong Peninsula. The zircon and apatite U-Pb ages are 156.9 ± 1.2 and 137.2 ± 2.4 Ma for the Linglong intrusion, 129.9 ± 1.0 and 125.0 ± 3.8 Ma for the Qujia intrusion, 119.5 ± 0.7 and 117.2 ± 1.8 Ma for the Liulinzhuang intrusion, 118.6 ± 1.0 and 111.6 ± 1.6 Ma for the Nansu intrusion, respectively. The coupled zircon and apatite data of these granitoids indicate a slow cooling rate (11.9 ℃/Ma) in the Late Jurassic, and rapid uplift and cooling (35.8–29.2 ℃/Ma) in the Early Cretaceous. The dramatically increased uplift and cooling period in the Early Cretaceous are contemporaneous with large-scale gold mineralization in the Jiaodong Peninsula. This implies that thermal upwelling of asthenosphere and related tectonic extension played an important role in gold remobilization and precipitation.

The Gaoaobei tungsten-molybdenum deposit is a newly discovered large-scale quartz-vein-type deposit in the Nanling metallogenic belt in South China. The ore bodies are hosted in the Indosinian granites and the Cambrian Xiangnan Group slates and are controlled by NWW-oriented faults, which are obviously different from the "five-story building" model in southern Jiangxi Province. The magmatic rocks in the study area are dominated by medium- to coarse-grained biotite monzogranite, with a few NW-oriented fine-grained granite dykes. The medium- to coarse-grained biotite monzogranite and fine-grained granite dykes have zircon U-Pb ages of 229.4 ± 1. 9 Ma (MSWD = 1.5) and 164.9 ± 3.3 Ma (MSWD = 0.75), respectively, corresponding to the Indosinian and Yanshanian magmatism. The monzogranites have higher contents of FeO, CaO, K₂O, P₂O₅, and TiO₂, while the granite dykes have slightly higher contents of SiO₂, Al₂O₃, MnO, and Na₂O. Their A/CNK values are 1.11–1.75 and 1.19–2.25, and the contents of CIPW normative corundum are 1.71%–6.66% and 2.41%–9.50%, suggesting both the monzogranites and granite dykes are S-type granite. The total amount of rare earth elements in the monzogranites (from 84.7 ppm to 129 ppm) is slightly lower than that in the granite dykes (from 128 ppm to 133 ppm). The Eu/Eu* values range from 0.12 to 0.30 in monzogranites and from 0.001 1 to 0.001 3 in granite dykes, indicating the fine-grained granites underwent more intense fractional crystallization. The monzogranite and granite dykes have high ⁸⁷Sr/⁸⁶Sr_i values of 0.716 9–0.719 3 and 0.728 25–0.728 80, low ε_Nd(t) values ranging from -10.2 to -9.6 and from -11.5 to -11.4, and T_DM2 ages of 1 835–1 785 and 1 957–1 946 Ma, respectively. These isotope data indicate their origin from the remelting of the Paleoproterozoic crustal materials. Combined with regional geology, it is concluded that the medium- to coarse-grained biotite monzogranite was formed in a post-collisional extensional environment. In addition, ⁴⁰Ar-³⁹Ar dating of the greisen type tungsten-molybdenum ore gave consistent plateau age of 164.0 ± 1.2 Ma, isochronal age of 162.0 ± 2.4 Ma and anti-isochronal age of 161.4 ± 1.8 Ma. Combined with the published molybdenite Re-Os age, the Gaoaobei tungsten-molybdenum deposit was formed at ~164 Ma, which is inferred to be genetically related to the contemporaneous fine-grained granite dykes (165 Ma). The deposit was likely formed during the large-scale magmatism and mineralization event in the early Yanshanian of the Nanling Range in an intra-continental extensional environment caused by the subduction of the paleo-Pacific plate. The late and small granite dykes within the large granite plutons thus require further attention during mineral prospecting in the regions.

The 1605 M7$ \mathrm{½} $ Earthquake is the only earthquake in the history of China that has caused large-scale land subsidence into the sea, with the total area of land subsidence exceeding 100 km². The disaster has led to the sinking of 72 villages. There is still no clear understanding of the source seismogenic fault of this earthquake. In this work, we conducted a detailed study of the middle segment of the Maniao-Puqian fault (MPF), which is the epicenter area, through geomorphological survey, data collection, shallow seismic exploration, cross-section drilling, and chronological dating. The results showed that the middle segment of the MPF zone is composed of three nearly parallel normal faults with a dextral strike-slip: "Macun-Luodou fault (F2-1), Haixiu-Dongyuan fault (F2-2), and Changliu-Zhuxihe fault (F2-3)". And F2-2 is composed of two secondary faults, namely F2-2′ and F2-2″, with a flower-shaped structure buried under the ground. It is distributed nearly east-west, dipping to the north and has experienced at least five stages of activities since the Miocene. The vertical activity rates of F2-2′ and F2-2″ are ~2.32 and ~2.5 mm/a, since the Holocene, respectively. There were eight cycles of transgression and regression since the Miocene. The fault activity resulted in the thickening of the Holocene strata with a slight dip to the south, on the hanging wall, showing V-shaped characteristics. The MPF is likely the source seismogenic fault of the M7$ \mathrm{½} $ earthquake that hit Qiongshan in 1605.

The influence of different types of roots on the soil is complex and still remains unclear. Four in-situ extrusion tests were conducted on two types of root systems, namely fibrous and tap root system, for three plants, Eleusine indica, Potentilla anserine, and Artemisia argyi, according to the classification in Botany, and the thrust-displacement curves and failure patterns of different samples were analysed by comparison to fill the aforementioned gap. Results reveal that the roots can reduce the characteristics of soil brittleness and enhance its capability to resist large deformation, and different root types contribute different effects to the strain-hardening behavior of the root-soil mass. The contribution of the fibrous root system to strength is limited, whilst the tap root system substantially enhances strength and stiffness. Results of failure patterns show that fibrous and tap root systems affect soil solidification and surface cracking reduction. However, the effect of the tap root system depends on the composition of lateral and tap roots: long and rich lateral roots are effective for resisting the creation of cracks, but thick tap roots with few and thin lateral roots may lead to several surface cracks.

Multi-layer slopes are widely found in clay residue receiving fields. A generalized horizontal slice method (GHSM) for assessing the stability of multi-layer slopes that considers the energy dissipation between adjacent horizontal slices is presented. In view of the upper-bound limit analysis theory, the energy equation is derived and the ultimate failure mode is generated by comparing the sliding surface passing through the slope toe (mode A) with that below (mode B). In addition, the influence of the number of slices on the stability coefficients in the GHSM is studied and the stable value is obtained. Compared to the original method (Chen's method), the GHSM can acquire more precise results, which takes into account the energy dissipation in the inner sliding soil mass. Moreover, the GHSM, limit equilibrium method (LEM) and numerical simulation method (NSM) are applied to analyze the stability of a multi-layer slope with different slope angles and the results of the safety factor and failure mode are very close in each case. The ultimate failure modes are shown to be mode B when the slope angle is not more than 28°. It illustrates that the determination of the ultimate sliding surface requires comparison of multiple failure modes, not only mode A.

A large number of laboratory investigations related to the permeability have been conducted on the sliding zones. Yet little attention has been paid to the particular sliding zones of the slide-prone Badong Formation. Here, we experimentally investigate the permeability nature and the mechanism of seepage in the viscous sliding zone of the Huangtupo Landslide. Saturated seepage tests have been performed first with consideration of six dry densities and thirteen hydraulic gradients, in conjunction with the mercury intrusion porosimetry test and scanning electron microscopy test for the microstructure analysis after seepage. The results show that seepage in the sliding zone soil does not follow Darcy's Law, since there is a threshold hydraulic gradient (i₀) below which no flow is observed and a critical hydraulic gradient (i_cr) over which the hydraulic conductivity (K) tends to be stable. The percentage of bound water could be responsible for the occurrence ofi₀ and i_cr. Furthermore, pore size distributions (PSD) less than 0.6 µm and between 10 and 90 µm exhibit positive and negative correlations with the i₀, respectively, indicating that the i₀ is related to the PSD. The mechanism accounting for this result is that pore water pressure forces fine clay particles into the surrounding large pores and converts arranged particles to discretely distributed ones, thereby weakening the connectivity of pores. The seepages in the sliding zones behave differently from that in the sliding mass and sliding bed in response to the permeability.

To investigate the stability and interaction mechanism of the slope-pile-footing system under surcharge effects, the finite difference method (FDM) was adopted to analyze the response laws of the stability of the reinforced slope, evolution of the critical slip surface, stress characteristic of retaining structures, deformation and failure modes of the slope foundation and building footing under surcharge parameters, including the surcharge intensity, the surcharge position, and the surcharge width. The results show that surcharge parameters significantly affect the stability and the deformation characteristics of the slope-pile-footing system. Specifically speaking, with the increasing surcharge intensity and the decreasing surcharge position and width, the deformation and failure mode of the system will gradually evolve in a direction that is harmful to its stability. The interaction mechanism of the slope-pile-footing system is further clarified as the load transfer of the building footing, the generation of the additional stress in the slope foundation, and the adjustment of pile bending moment due to the stress redistribution. Correspondingly, the safety of anti-slide piles will determine the stability of the slope foundation and building footing. These findings are expected to provide guidance for the comprehensive development and utilization of filled slopes after reinforcement.

Tunnel seismic advance prediction can effectively reduce the construction risk during tunnel excavation. Compared with the 2-D method, the 3-D method is more conducive to describing the spatial characteristics of the geological body by adding the seismic data in the vertical direction. However, some drawbacks still need improvement in the current 3-D tunnel seismic prediction method. (1) The geometry is complex, which is destructiveness, high cost, and time-consuming, and will delay the tunnel construction schedule. (2) Illumination of the anomalous body is insufficient, and the precision of migration imaging is low. (3) Shot points are far away from the tunnel face, the energy loss at the shot points is more serious. (4) The received signals at the tunnel wall have the surface wave with strong energy when the shot points are placed on the tunnel wall. (5) The geometry is not linear, so the directional filtering method cannot be used to extract the reflection wave. To overcome the drawbacks of the current prediction method, a new 3-D symmetrical tunnel seismic prediction method is proposed. Six geophones are installed on the tunnel wall, two on the left side, two on the right side, and two on the top side. Twenty-four shot points are placed on the tunnel face and near both sides of the tunnel wall, twelve shot points on the left side and twelve shot points on the right side. The shot points will move along with the forward excavation of the tunnel. The wavefield analysis, illumination statistics, and 3-D reverse time migration imaging are used to evaluate the proposed method. The result of modeled data indicates that the proposed 3-D geometry has some advantages: (1) the geometry is simple and the geophone installation time is short; (2) it has high illumination energy, wide illumination range, and can improve the prediction distance and imaging accuracy; (3) the proposed 3-D method can better estimate the velocity of surrounding rock and is more conducive to extracting the reflection wave with high resolution.

The upstream Jinsha River, located in the eastern Tibetan Plateau, has been experiencing intense geological hazards characterized by a high density of ancient landslides, significant deformation and reactivation challenges. In this study, remote sensing interpretation, field investigations, and Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technologies have been employed. Along a 17 km stretch of the Jinsha River, specifically in the Xiongba-Sela segment, 16 large-scale ancient landslides were identified, 9 of which are currently undergoing creeping deformation. Notably, the Sela and Xiongba ancient landslides exhibit significant deformation, with a maximum deformation rate of -192 mm/yr, indicating a high level of sliding activity. The volume of the Sela ancient landslide is estimated to be 1.8 × 10⁸ to 4.5 × 10⁸ m³, and characterized by extensive fissures and long-term creeping deformation. The SBAS-InSAR results revealed significant spatial variations in the deformation of the Sela ancient landslide, generally displaying two secondary zones of intense deformation, and landslide deformation exhibits nonlinear behavior with time. Between January 2016 and February 2022, Zone Ⅲ₁ on the southwest side of the Sela ancient landslide, experienced a maximum cumulative deformation of -857 mm, with a maximum deformation rate of -108 mm/yr. Zone Ⅲ₂, on the northeast side of the Sela ancient landslide, the maximum cumulative deformation was -456 mm, with a maximum deformation rate of -74 mm/yr; among these, the H₂ and H₄ secondary bodies on the south side of Ⅲ₁ are in the accelerative deformation stage and at the Warn warning level. We propose that the large-scale flood and debris flow disasters triggered by the Baige landslide-dammed lake-dam broken disaster chain in Tibetan Plateau during October and November 2018 caused severe erosion at the foot of downstream slopes. This far-field triggering effect accelerated the creep of the downstream ancient landslides. Consequently, the deformation rate of Zone Ⅲ₂ of the Sela ancient landslide increased by 6 to 8 times, exhibiting traction-type style reactivation. This heightened activity raises concerns about the potential for large-scale or overall reactivation of the landslide, posing a risk of damming the Jinsha River and initiating a dam-break disaster chain. Our research on the reactivation characteristics and mechanisms of large ancient landslides in high deep-cut valleys provides valuable guidance for geological hazard investigation and risk prevention.

Synthesized iron oxyhydroxide was applied for the adsorptive removal of As(V) and As(III) from the aquas media. Additionally, this investigation highlighted the synergistic effect of calcium carbonate in conjunction with iron oxyhydroxide, resulting in enhanced removal efficiency. The experiment was conducted under various conditions: concentration, dosage, pH, agitation, and temperature. Material characterizations such as Brunauer Emmett Teller, X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy were implied to understand adsorption mechanisms. The Langmuir model revealed optimal concentrations for As(V) = 500 μg/L at pH-5 and As(III) = 200 μg/L at pH-7, resulting in 95% and 93% adsorption efficiencies, respectively. Maximum adsorption capacities "q_mˮ were found to be 1 266.943 μg/g for As(V) and 1 080.241 μg/g for As(III). Freundlich model demonstrated favorable adsorption by indicating "n > 1ˮ such as As(V) = 2.542 and As(III) = 2.707; similarly, the speciation factor "R_L < 1" for both species as As(V) = 0.1 and As(III) = 0.5, respectively. The kinetic study presented a pseudo-second-order model as best fitted, indicating throughout chemisorption processes for removing As(V) and As(III). Furthermore, incorporating calcium carbonate presented a significant leap in the removal efficiency, indicating As(V) from 95% to 98% and As(III) from 93% to 96%, respectively. Our findings offer profound motivation for developing effective and sustainable solutions to tackle arsenic contamination, underscoring the exceptional promise of iron oxyhydroxide in conjunction with calcium carbonate to achieve maximum removal efficiency.

Luan River is the main water source in Beijing-Tianjin-Hebei region, northern China, where the groundwater system is vulnerable and pollution issue is serious. It is significant for regional groundwater resources protection to identify the hydrogeochemistry evolution and affecting factors along flow direction occurred in the upper reaches, especially the surface water-groundwater (SW-GW) conversion relationship. In this study, recharge, conversion and geochemistry evolution of SW and GW were elucidated based on physical-hydrochemical indicators and stable isotopes in 36 GW samples and 20 SW samples, which were collected in July 2019 and July 2020. The factor analysis was further utilized to determine the main factors responsible for regional hydrogeochemical evolution. Results indicate that GW recharged SW in plateau area, and SW and GW recharged each other in typical Alpine valley area. The hydrochemical types are HCO₃^-Ca·Mg and HCO₃-Ca, and the hydrochemical evolution is dominated by weathering of silicate and carbonate minerals. The cation exchange adsorption has minor impact on groundwater hydrochemistry. The rise of SO₄^2- and NO₃^- contents in groundwater is related to industrial and agricultural activities. The main controlling factors of SW hydrochemical components included recharge from groundwater, industrial and mining activities, explaining 90.04% of data variance. However, water-rock interaction, agricultural and domestic sewage are responsible for GW quality, accounting for 83.38%.

A knowledge graph (KG) is a knowledge base that integrates and represents data based on a graph-structured data model or topology. Geoscientists have made efforts to construct geoscience-related KGs to overcome semantic heterogeneity and facilitate knowledge representation, data integration, and text analysis. However, there is currently no comprehensive paleontology KG or data-driven discovery based on it. In this study, we constructed a two-layer model to represent the ordinal hierarchical structure of the paleontology KG following a top-down construction process. An ontology containing 19 365 concepts has been defined up to 2023. On this basis, we derived the synonymy list based on the paleontology KG and designed corresponding online functions in the OneStratigraphy database to showcase the use of the KG in paleontological research.

Geological reports are a significant accomplishment for geologists involved in geological investigations and scientific research as they contain rich data and textual information. With the rapid development of science and technology, a large number of textual reports have accumulated in the field of geology. However, many non-hot topics and non-English speaking regions are neglected in mainstream geoscience databases for geological information mining, making it more challenging for some researchers to extract necessary information from these texts. Natural Language Processing (NLP) has obvious advantages in processing large amounts of textual data. The objective of this paper is to identify geological named entities from Chinese geological texts using NLP techniques. We propose the RoBERTa-Prompt-Tuning-NER method, which leverages the concept of Prompt Learning and requires only a small amount of annotated data to train superior models for recognizing geological named entities in low-resource dataset configurations. The RoBERTa layer captures context-based information and longer-distance dependencies through dynamic word vectors. Finally, we conducted experiments on the constructed Geological Named Entity Recognition (GNER) dataset. Our experimental results show that the proposed model achieves the highest F1 score of 80.64% among the four baseline algorithms, demonstrating the reliability and robustness of using the model for Named Entity Recognition of geological texts.