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Journal of Earth Science 2025年

作者： Yongheng Zhou Yaming Tang Bo Hong Fan Feng Longhui Wang Institute of geological survey， China University of Geosciences (Wuhan) Institute of Earth Environment， Chinese Academy of Sciences Xi'an geological survey Center China geological survey Chinese Academy of geological Sciences

Malan loess is highly water-sensitive， with its shear strength， particularly cohesive strength， significantly decreasing under the influence of water. The Western Shanxi Loess Plateau （WSLP） is especially prone to loess landslides， which are closely linked to rainfall infiltration. Understanding the regional variation of Malan loess cohesion (cm) and its distribution in relation to the developmental intensity of landslides in this area can provide essential scientific evidence for effective landslide prevention. Loess landslides and Malan loess were selected as the objects of study for the current research. The regional variation and distribution pattern of the cmwere revealed through undisturbed loess direct shear tests and Inverse Distance Weighting （IDW） interpolation. The relationship between the developmental intensity of landslide and the regional variation of the cmwas explored using the Cumulative Sum Variable Dimension Fractal （CSVDF）， Frequency Ratio （FR） model， and Certainty Factor （CF） model. The following conclusions were drawn: Results from the direct shear tests and IDW method indicate that the cmtends to decrease from south to north and exhibits a positively skewed spatial distribution pattern. The CSVDF results indicates a similarity between the regional variation of the cmand the development intensity of loess landslides. The FR and CF results reveal that loess landslides are more likely to occur when the cmis between 0 and 16.14 kPa.

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Prediction of Shear Bond Strength of Asphalt Concrete Pavement Using Machine Learning Models and Grid Search Optimization Technique

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 691-712页

作者： Quynh-Anh Thi Bui Dam Duc Nguyen Hiep Van Le Indra Prakash Binh Thai Pham Civil Engineering Department University of Transport Technology54 Trieu KhucThanh XuanHanoi100000Vietnam DDG(R)geological survey of India Gandhinagar382010India

Determination of Shear Bond strength(SBS)at interlayer of double-layer asphalt concrete is crucial in flexible pavement *** study used three Machine Learning(ML)models,including K-Nearest Neighbors(KNN),Extra Trees(ET),and Light Gradient Boosting Machine(LGBM),to predict SBS based on easily determinable input ***,the Grid Search technique was employed for hyper-parameter tuning of the ML models,and cross-validation and learning curve analysis were used for training the *** models were built on a database of 240 experimental results and three input variables:temperature,normal pressure,and tack coat *** validation was performed using three statistical criteria:the coefficient of determination(R2),the Root Mean Square Error(RMSE),and the mean absolute error(MAE).Additionally,SHAP analysis was also used to validate the importance of the input variables in the prediction of the *** show that these models accurately predict SBS,with LGBM providing outstanding ***(Shapley Additive explanation)analysis for LGBM indicates that temperature is the most influential factor on ***,the proposed ML models can quickly and accurately predict SBS between two layers of asphalt concrete,serving practical applications in flexible pavement structure design.

关键词： Shear bond asphalt pavement grid search optimization machine learning

Stable isotope paleohydrology and chemostratigraphy of the Albian Wayan Formation from the wedge-top depozone,North American Western Interior Basin

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Science China Earth Sciences 2017年第1期60卷 44-57页

作者： Jeffrey B.ROSS Greg A.LUDVIGSON Andreas MOLLER Luis A.GONZALEZ J.D.WALKER Department of Geology University of Kansas kansas geological survey University of Kansas

Understanding of the role of atmospheric moisture and heat transport in the climate system of the Cretaceous greenhouse world represents a major challenge in Earth system science. Stable isotopic paleohydrologic data from mid-Cretaceous paleosols in North America, from paleoequatorial to paleoArctic latitudes, have been used to constrain the oxygen isotope mass balance of the Albian hydrologic cycle. Over the range from 40°-50°N paleolatitude, sideritic paleosols predominate, indicating paleoenvironments with positive precipitation-evaporation （P-E） balances. Local exceptions occur on leeward side of the Sevier Orogen, where calcic paleosols in the wedge-top depozone record paleoenvironments with negative P-E balances in the orographic rain shadow. Stratigraphic sections in the Wayan Formation of Idaho （WF） were sampled from the wedge-top depozone. The units consist of stacked m-scale mudstone paleosols separated by m-scale sandstone-siltstone beds. Sections were sampled for organic carbon isotope profiles, and B-horizons from 6 well-developed paleosols were sampled for detrital zircons to determine maximum depositional ages. The first of these from the WF has produced a U-Pb concordia age of 101.0±1.1 Ma. This same WF section has produced a stratigraphic trend of upwardly decreasing δ18C values ranging from -24‰ upwards to -27‰ VPDB, suggesting correlation to the late Albian C15 C-isotope segment. Pedogenic carbonates from the WF principally consist of micritic calcite, with carbon-oxygen isotope values that array along meteoric calcite lines （MCLs） with δ18O values that range from -9.47‰ up to -8.39‰ VPDB. At approximately 42°N paleolatitude, these MCL values produce calculated paleoprecipitation values of-8.12‰ to -7.04‰ VSMOW, a range that is consistent with the estimates produced from other proxies at the same paleolatitudes across North America. These results indicate that despite the orographic rain shadow effect, the processes of meridional atmospheric moist

关键词： Cretaceous Paleoclimate Wayan Formation Pedogenic carbonates Geochronology

High-Frequency Rayleigh-Wave Method

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Journal of China University of Geosciences 2009年第3期20卷 563-579页

作者： Richard D Miller 徐义贤罗银河陈超刘江平 Julian Ivanov kansas geological survey The University of KansasLawrence KS 66047 USA Institute of Geophysics and Geomatics China University of Geosciences kansas geological survey The University of Kansas

High-frequency （〉2 Hz） Rayleigh-wave data acquired with a multichannel recording system have been utilized to determine shear （S）-wave velocities in near-surface geophysics since the early 1980s. This overview article discusses the main research results of high-frequency surface-wave techniques achieved by research groups at the kansas geological survey and China University of Geosciences in the last 15 years. The multichannel analysis of surface wave （MASW） method is a non-invasive acoustic approach to estimate near-surface S-wave velocity. The differences between MASW results and direct borehole measurements are approximately 15% or less and random. Studies show that simultaneous inversion with higher modes and the fundamental mode can increase model resolution and an investigation depth. The other important seismic property, quality factor （Q）, can also be estimated with the MASW method by inverting attenuation coefficients of Rayleigh waves. An inverted model （S-wave velocity or Q） obtained using a damped least-squares method can be assessed by an optimal damping vector in a vicinity of the inverted model determined by an objective function, which is the trace of a weighted sum of model-resolution and model-covariance matrices. Current developments include modeUng high-frequency Rayleigh-waves in near-surface media, which builds a foundation for shallow seismic or Rayleigh-wave inversion in the time-offset domain; imaging dispersive energy with high resolution in the frequency-velocity domain and possibly with data in an arbitrary acquisition geometry, which opens a door for 3D surface-wave techniques; and successfully separating surface-wave modes, which provides a valuable tool to perform S-wave velocity profiling with high-horizontal resolution.

关键词： Rayleigh wave dispersion high mode mode separation seismic modeling model appraisal.

Research on the deformation mechanism of flexural toppling deep-seated landslides based on large centrifuge physical model testing: A case study of the Genie landslide in the Tibetan Plateau

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Journal of Earth Science 2025年

作者： Shichao Cao Xiujun Dong Changbao Guo Ruian Wu Zhihua Yang Guang Zheng Xiaoqiang Zhu State Key Laboratory of Geohazard Prevention and Geoenvironment Protection， Chengdu University of Technology Institute of Geomechanics， Chinese Academy of geological Sciences Key Laboratory of Active Tectonics and geological Safety， Ministry of Natural Resources

Flexural toppling is a widespread failure mode in natural and excavated anti-inclined rock slopes of the eastern Tibetan Plateau， which can further evolve into large deep-seated landslides， posing significant threats to the construction and operation of important infrastructure. In this study， we took the large deep-seated Genie landslide as a case study and established a centrifuge physical model to analyze the deformation mechanism and evolutionary process of flexural toppling deep-seated landslides under the effect of gravity. The results indicate that the geomechanical mode of landslide instability is characterized by flexural toppling-shearing-sliding， with the deformation process could be divided into three stages: initial slow deformation stage marked by crack generation， rapid deformation stage characterized by the expansion and fracturing of cracks， and a low-speed deformation stage characterized by creep. Notably， the sliding surfaces do not adhere strictly to predefined bending zones but develop cracks along the bending parts， which gradually expand and penetrate deeper， eventually forming multiple potential sliding surfaces. The analysis of the entire process deformation evolution of flexural toppling deep-seated landslides suggests that the rapid deformation stage is the optimal time to take action for landslide prevention and control. The study demonstrates that the shear strength also plays a key factor in the evolution of flexural toppling. The research reveals the deformation mechanism and evolutionary process of large deep-seated landslides in deep-cut canyon areas， providing valuable reference for the prediction， assessment， and prevention of such slopes and landslides.

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Foreword

Journal of China University of Geosciences 2009年第3期20卷 493-495页

作者： Jianghai Xia kansas geological survey The University of Kansas Lawrence KS 66047 USA

The Chinese Geophysical Society and China University of Geosciences （CUG） hosted the last three International Conferences on Environmental and Engineering Geophysics （ICEEG） on the campus of CUG in Wuhan, China, biannually from 2004 to 2008. The ICEEG has become one of the main international conferences on near-surface geophysics in the world and the most influential near-surface geophysics con- ference in China. More than 200 people from more than 10 countries attended each conference, including practitioners, academicians, researchers, and students.

关键词： International China Society Chinese three

Genesis of the Wulong gold deposit,Liaoning Province,NE China:Constrains from noble gases,radiogenic and stable isotope studies

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Geoscience Frontiers 2020年第2期11卷 547-563页

作者： Peng Zhang Linlin Kou Yan Zhao Zhongwei Bi Deming Sha Renping Han Zhumin Li Shenyang geological survey Center China geological survey

The Wulong lode deposit contains over 80 tonnes of gold with an average grade of 5.35 g/*** is one of the largest deposits in Dandong City,Liaoning Province in northeast *** studies on the deposit focused on its geological characteristics,geochemistry,fluid inclusions,and the timing of gold ***,controversy remains regarding the origin of the ore-forming fluids and metals,and the genesis of the gold *** paper presents zircon U-Pb and pyrite Rb-Sr ages and S,Pb,He,and Ar isotopic results along with quartz H and O isotopic data for all litho-units associated with the *** ablation inductively coupled mass spectrometry measurements yielded zircon U-Pb dates for samples of pre-mineralization rocks like granite porphyry dike,the Sanguliu granodiorite,fine-grained diorite,and syn-mineralization diorite,as well as post-mineralization dolerite,and lamprophyre;their emplacement ages are 126±1 Ma,124±1 Ma,123±1 Ma,120±1 Ma,119±2 Ma,and 115±2 Ma,*** pyrite Rb-Sr isochron age is 119±1 Ma,indicating that both magmatism and mineralization occurred during the Early *** δ18OH2 O values of ore-forming hydrothermal fluids from the quartz-polymetallic sulfide vein stage vary from 4.8‰to 6.5‰,and the δDv-SMOW values are between-67.7‰and-75.9‰,indicating that the ore-forming fluids were primarily *** noble gas isotope compositions of fluid inclusions hosted in pyrite suggest that the ore-forming fluids were dominantly derived from crustal sources with minor mantle *** isotopic values of pyrite vary between 0.2‰and 3.5‰,suggesting that S was derived from a homogeneous magmatic source or possibly from fluids derived from the *** Pb isotopic compositions of sulfides（207 Pb/204 Pb=15.51-15.71,206 Pb/204 Pb=17.35-18.75,208 Pb/204 Pb=38.27-40.03） indicate that the Pb of the Wulong gold deposit is a mixture of crust and mantle *** and geochemical data,together with the region

关键词： The Wulong gold deposit Zircon U-Pb Pyrite Rb-Sr H-He-O-Ar-S-Pb isotopes Liaodong Peninsula

Land 3D-Seismic Data: Preprocessing Quality Control Utilizing survey Design Specifications, Noise Properties, Normal Moveout, First Breaks, and Offset

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Journal of China University of Geosciences 2009年第3期20卷 640-648页

作者： Abdelmoneam Raef Geology Department Kansas State UniversityManhattan Kansas USA Formerly Kansas Geological Survey The University of KansasLawrence USA

The recent proliferation of the 3D reflection seismic method into the near-surface area of geophysical applications, especially in response to the emergence of the need to comprehensively characterize and monitor near-surface carbon dioxide sequestration in shallow saline aquifers around the world, justifies the emphasis on cost-effective and robust quality control and assurance （QC/QA） workflow of 3D seismic data preprocessing that is suitable for near-surface applications. The main purpose of our seismic data preprocessing QC is to enable the use of appropriate header information, data that are free of noise-dominated traces, and/or flawed vertical stacking in subsequent processing steps. In this article, I provide an account of utilizing survey design specifications, noise properties, first breaks, and normal moveout for rapid and thorough graphical QC/QA diagnostics, which are easy to apply and efficient in the diagnosis of inconsistencies. A correlated vibroseis time-lapse 3D-seismic data set from a CO2-flood monitoring survey is used for demonstrating QC diagnostics. An important by-product of the QC workflow is establishing the number of layers for a refraction statics model in a data-driven graphical manner that capitalizes on the spatial coverage of the 3D seismic data.

关键词： preprocessing quality control 3D seismic 4D seismic trace header geometry vertical stacking.

Gas Sources of Natural Gas Hydrates in the Shenhu Drilling Area, South China Sea: Geochemical Evidence and geological Analysis

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Acta Geologica Sinica(English Edition) 2013年第3期87卷 767-776页

作者： ZHU Youhai HUANG Xia FU Shaoying SU Pibo Oil & Gas survey China Geological Survey Institute of Mineral Resources Chinese Academy of Geological Sciences Guangzhou Marine geological survey

The Shenhu gas hydrate drilling area is located in the central Baiyun sag, Zhu I! depression, Pearl River Mouth basin, northern South China Sea. The gas compositions contained in the hydrate-bearing zones is dominated by methane with content up to 99.89% and 99.91%. The carbon isotope of the methane （δ^13C1） are -56.7%0. and -60.9%0, and its hydrogen isotope （δD） are -199%0 and -180%0, respectively, indicating the methane from the microbial reduction of CO2. Based on the data of measured seafloor temperature and geothermal gradient, the gas formed hydrate reservoirs are from depths 24-1699 m below the seafloor, and main gas-generation zone is present at the depth interval of 416-1165 m. Gas-bearing zones include the Hanjiang Formation, Yuehai Formation, Wanshan Formation and Quaternary sediments. We infer that the microbial gas migrated laterally or vertically along faults （especially interlayer faults）, slump structures, small-scale diapiric structures, regional sand beds and sedimentary boundaries to the hydrate stability zone, and formed natural gas hydrates in the upper Yuehai Formation and lower Wanshan Formation, probably with contribution of a little thermogenic gas from the deep sedments during this process.

关键词： natural gas hydrate methane microbial gas gas source migration South China Sea

Genesis of the Maoling gold deposit in the Liaodong Peninsula:Constraints from a combined fluid inclusion,C-H-O-S-Pb-He-Ar isotopic and geochronological studies

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Geoscience Frontiers 2022年第4期13卷 11-33页

作者： Peng Zhang Linlin Kou Yan Zhao Deming Sha Shenyang geological survey Center China Geological SurveyShenyang 110034China

The large tonnage Maoling gold deposit(25 t@3.2 g/t)is located in the southwest Liaodong Peninsula,North China *** deposit is hosted in the Paleoproterozoic metamorphic *** stages of mineralization were identified in the deposit:(stageⅠ)quartz-arsenopyrite±pyrite,(stageⅡ)quartz-goldarsenopyrite-pyrrhotite,(stageⅢ)quartz-gold-polymetallic sulfide,and(stageⅣ)*** this paper,we present fluid inclusion,C-H-O-S-Pb-He-Ar isotope data,zircon U-Pb,and gold-bearing sulfide(*** and pyrrhotite)Rb-Sr age of the Maoling gold deposit to constrain its genesis and ore-forming *** types of fluid inclusions were distinguished in quartzbearing veins,including liquid-rich two-phase(WL type),gas-rich two-phase(GL type),and daughter mineral-bearing fluid inclusions(S type).Fluid inclusions data show that the homogenization at temperatures 197 to 372°C for stageⅠ,126 to 319°C for stageⅡ,119 to 189°C for stageⅢ,and 115 to 183°C for stageⅣ,with corresponding salinities of 3.7 to 22.6 wt.%,4.7 to 23.2 wt.%,5.3 to 23.2 wt.%,and 1.7 to14.9 wt.%Na Cl equiv.,*** boiling was the critical factor controlling the gold and associated sulfide precipitation at *** and oxygen stable isotopic analyses for quartz yielded δ^(18)O=-5.0‰ to 9.8‰ and δD=-133.5‰ to-77.0‰.Carbon stable isotopic analyses for calcite and ankerite yielded δ^(13)C=-2.3‰to-1.2‰ and O=7.9‰ to 14.1‰.The C-H-O isotope data show that the oreforming fluids were originated from magmatic water with meteoric water input during *** inclusions in arsenopyrite have ^(3)He/^(4)He ratios of 0.002 Ra to 0.054 Ra,and ^(40)Ar/^(36)Ar rations of 1225 to 3930,indicating that the ore-forming fluids were dominantly derived from crustal sources almost no mantle *** isotopic values of Maoling fine-grained granite range from6.‰1 to 9.8‰,with a mean of 7.7‰,δ^(34)S values of arsenopyrite from the mineralized phyllite(host rock)range fr

关键词： Geochronology Fluid inclusions Isotope geochemistry Maoling gold deposit Liaodong Peninsula