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Interpreting Larix principis-rupprechtii radial growth in northern China based on the Vaganov-Shashkin model

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Journal of Forestry Research 2024年第3期35卷 99-110页

作者： Jiachuan Wang Shuheng Li Qiang Li Yili Guo Yijie Han Qi Liu Yiqi Zhao College of Urban and environmental Sciences Northwest UniversityXi'an 710127People's Republic of China Institute of Global environmental Change Xi'an Jiaotong UniversityXi'an 710049People's Republic of China Shaanxi key laboratory of Earth Surface System and environmental Carrying Capacity Northwest UniversityXi'an 710127People's Republic of China state key laboratory of Loess and Quaternary geology Institute of Earth EnvironmentChinese Academy of SciencesXi'an 710061People's Republic of China

Changes in annual radial growth is an important indication of climate change. Dendroclimatology studies in northern China have focused on linear statistical analysis,but lacking studies based on the process of ring formation to clarify the radial growth of trees. Tree-ring width standard chronology(STD) was established using samples of Larix principis-rupprechtii collected at 2303 m altitude on Luya Mountain. Using the Vaganov-Shashkin(VS) model to simulate growth and development, the internal physiological mechanism of radial growth is identified. It was concluded that:(1) the growing season of L. principis-rupprechtii was May to September;(2) soil moisture was a significant factor in the early and late growing seasons, and temperature was the dominant factor in its main growth period;and(3) formation of narrow ring widths was closely related to drought stress, the development of wide ring widths will be restricted by increasing future temperatures. The VS model is applicable for radial growth simulation of subalpine coniferous forests and for guiding the cultivation of local tree species in the future.

关键词： Vaganov-Shashkin model Larix principis-rupprechti Tree-ring width Annual growth

An overview and perspective of identifying lunar craters

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Science China Earth Sciences 2024年第5期67卷 1395-1416页

作者： Yan JIANG Changyi Xu Ling CHEN state key laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100029China key laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100049China

The spatiotemporal evolution of lunar impact craters is crucial for investigating lunar interior structure,internal and external dynamic processes,and interplanetary impact *** in lunar crater identification are reviewed based on topography and gravity data,and the features and mechanisms of topographic or buried craters are analyzed regarding morphology,gravity anomalies,gravity gradients,and the underlying crust-mantle interface *** on the compiled crater catalog,the early lunar impact flux and thermal evolution are further discussed according to the basin ages and their interior *** some ancient impact basins,the crater size-frequency distribution measurements revealed age discrepancies from previous studies,suggesting that the lunar late heavy bombardment event started at~3.95 *** degraded bulge structures of the crust-mantle interface beneath mare basins reveal that these basins formed on the lunar crust surface under high-temperature conditions and underwent prolonged relaxation compared to highland ***,we reveal that the up-to-date identification of lunar buried craters remains inaccurate and incomplete,preventing us from accurately reconstructing lunar and interplanetary impact ***,we propose that a gravity model constructed using localized orthogonal basis functions can be useful for identifying lunar craters.

关键词： Moon Gravity field Craters Impact flux Early evolution

Integrated wellbore-reservoir-geomechanics modeling for enhanced interpretation of distributed fiber-optic strain sensing data in hydraulicfracture analysis

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第8期16卷 3136-3148页

作者： Lijun Liu Xinglin Guo Xiaoguang Wang state key laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu610059China Tianfu Yongxing laboratory Chengdu610213China College of Energy Chengdu University of TechnologyChengdu610059China state key laboratory of Oil and Gas Reservoir geology and Exploitation Chengdu610059China

Fiber-optic distributed strain sensing(FO-DSS)has been successful in monitoring strain changes along horizontal wellbores in hydraulically fractured ***,the mechanism driving the various FO-DSS responses associated with near-wellbore hydraulic fracture properties is still *** address this knowledge gap,we use coupled wellbore-reservoir-geomechanics simulations to study measured strain-change behavior and infer hydraulic fracture *** crossflow among fractures is captured through explicit modeling of the transient wellbore *** addition,local grid refinement is applied to accurately capture strain changes along the fiber.A Base Case model was designed with four fractures of varying properties,simulating strain change signals when the production well is shut-in for 10 d after 240 d of production and reopened for 2 ***-pressure plots for different fracture clusters were used to gain insights into inferring fracture properties using DSS *** comparing the model with and without the wellbore,distinct strain change signals were observed,emphasizing the importance of incorporating the wellbore in FO-DSS *** effects of fracture spacing and matrix permeability on strain change signals were thoroughly *** results of our numerical study can improve the understanding of the relation between DSS signals and fracture hydraulic properties,thus maximizing the value of the dataset for fracture diagnostics and characterization.

关键词： Distributed strain sensing Fracture diagnostic Coupled flow and geomechanics Transient wellbore flow

Late Paleozoic to early Mesozoic volcanic-sedimentary history of the southeastern margin of the Central Asian Orogenic Belt: Timing of uplift of the Inner Mongolia paleo-uplift

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Science China Earth Sciences 2024年

作者： Wenxing HAO Jin-Hui YANG Guang ZHU state key laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences School of Resource and environmental Engineering Hefei University of Technology

The Kulun region is located in the eastern Bainaimiao arc belt on the southeastern margin of the Central Asian Orogenic Belt（CAOB）, adjacent to the North China Craton（NCC） to the south. This region records the closure of the PaleoAsian Ocean during the Paleozoic to early Mesozoic and is key to study the tectonic evolution of the northern margin of the *** conducted zircon U-Pb geochronology and Hf isotope analysis of volcanic-sedimentary and intrusive rocks in the Kulun region. The volcanic-sedimentary rocks were previously assigned an early Carboniferous age, but include volcanic rocks with ages of 267–266 Ma and sedimentary rocks with youngest detrital zircon age peaks of 265–244 Ma, which were intruded by a granite with an age of 242 Ma. This indicates that these rocks are actually middle Permian to Middle Triassic in age（267–242Ma） and correspond to the Qingfengshan and Liujiagou formations. Moreover, two volcanic rock samples have high εHf（t） values（+1.6 to +16.1） and relatively young two-stage Hf model ages（1095–327 Ma）, indicating their sources associated with the CAOB. The age spectra and Hf isotopic characteristics of detrital zircons from the sedimentary rocks suggest that, during the middle Permian to Middle Triassic, the sedimentary provenance in the Kulun region was mainly the CAOB. However, by the Early Jurassic, the provenance changed to the NCC（i.e., the Inner Mongolia Paleo-uplift, IMPU）. This result, combined with the development of a series of conglomerates on the northern margin of the NCC in the Late Triassic（i.e., Xingshikou, Xiaoyingzi,and Xiaohekou formations）, indicates the Kulun region experienced an abrupt change in paleogeography during the Late Triassic, with the IMPU undergoing significant uplift and thus becoming the main sediment source in the Kulun region. Based on the Late Triassic alkaline igneous belt（235–215 Ma） in the IMPU, we speculate that this uplift was caused by detachment of the southward-subducting Paleo-Asian oceanic

关键词： Central Asian Orogenic Belt the North China Craton Zircon geochronology Hf isotopes Inner Mongolia Paleouplift

Primary and Secondary Calcite in Chinese Loess Distinguished by Crystallinity and Implications for Illuviation Depth and East Asian Summer Monsoon Intensity

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Journal of Earth Science 2024年

作者： Yan Zhao Kangjun Huang Yuanqiang Guo Pan Zhang Yawen Lu Long Ma state key laboratory of Continental Dynamics， Shaanxi key laboratory of Early Life and Environment， Department of geology， Northwest University

The crystallinity has the potential to distinguish the primary and secondary calcite in Chinese loess， which then provides insights into illuviation depth and variations of the East Asian summer monsoon. However， this aspect has been rarely investigated. In this study， we defined the crystallinity of calcite as the Height/Area (H/A) ratio of the diffracted peak at crystal face (1 0 4). The H/A ratio inversely correlates with the average width of the diffracted peak， where a higher H/A ratio indicates higher crystallinity of calcite. Through the mixing and synthetic experiments， we found that the H/A ratio is minimally affected by factors such as calcite content， deposition temperature or rate but significantly influenced by the ionic impurity and the mixing proportion of different calcites. Subsequently， we examined desert samples of loess sources and loess carbonate nodules. Desert samples predominantly consist of primary calcite which inherits characteristics from cryptocrystalline limestone with high levels of ionic impurities resulting in low H/A ratio of 4.30 ± 0.51. In contrast， loess carbonate nodules contain abundant secondary calcite precipitated within soil interstices with low levels of ionic impurities leading to a significantly higher H/A ratio of 7.76 ± 0.82. Consequently， higher H/A ratios during interglacial periods compared to glacial periods are attributed to variations in relative proportions between primary and secondary calcite in loess sequences. The thickness， between the glacial-interglacial boundary and the depth where the H/A ratio starts to increase from the bottom to the top in the loess layer， can be used to indicate the illuviation depth of upper-soil carbonates and the intensity of the East Asian summer monsoon. This proxy can be further applied in long-term loess sequences to uncover the summer monsoon evolution.

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Polymetamorphism of the ultrahigh-temperature granulites in the Rauer Group,East Antarctica:new evidence from zircon SHRIMP U-Pb ages

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Advances in Polar Science 2024年第2期35卷 192-205页

作者： TONG Laixi LIU Zhao LI Chao LU Junsheng YANG Wenqiang WANG Yanbin state key laboratory of Continental Dynamics Department of GeologyNorthwest UniversityXi’an 710069China Institute of geology Chinese Academy of Geological SciencesBejing 100037China

The Rauer Group is located on the eastern margin of the early Paleozoic Prydz Belt in East Antarctica,and the typical ultrahigh-temperature(UHT,>900℃)granulites outcrop on Mather ***,the timing of UHT metamorphism and P–T path of the UHT granulites have long been debated,which is critical to understanding the tectonic nature and evolution history of the Prydz ***,both a sapphirine-bearing UHT metapelitic granulite and a garnet-bearing UHT mafic granulite are selected for zircon SHRIMP U-Pb age *** results show that metamorphic zircon mantles yield weighted mean^(206)Pb/^(238)U ages of 918±29 Ma and 901±29 Ma for the metapelitic and mafic granulites,respectively,while zircon rims and newly grown zircons yield weighted mean^(206)Pb/^(238)U ages of 523±9 Ma and 532±11 Ma,*** new zircon age data suggest that the UHT granulites may have experienced polymetamorphism,in which pre-peak prograde stage occurred in the early Neoproterozoic Grenvillian orogenesis(1000–900 Ma),whereas the UHT metamorphism occurred in the late Neoproterozoic to early Paleozoic Pan-African orogenesis(580–460 Ma).This implies that P–T path of the UHT granulites should consist of two separate high-grade metamorphic events including the Grenvillian and Pan-African events,which are supposed to be related to assembly of Rodinia and Gondwana supercontinents respectively,and hence the overprinting UHT metamorphic event may actually reflect an important intracontinental reworking.

关键词： ultrahigh-temperature granulites zircon SHRIMP U-Pb ages polymetamorphism Rauer Group East Antarctica

Microbial communities and their influencing factors in the sediment of upper and mid-lower reaches of the Yellow River

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Journal of Earth Science 2024年

作者： Yanmin Zhang Zewei Gui Xiaofei Gao Jingxiao Zhang Yunni Gao Man Zhang Guokun Yang Xindang Zhang Xulu Chang Zixuan Gan Xiaolin Meng Xuejun Li Hongchen Jiang College of Fisheries， Henan Normal University state key laboratory of Biogeology and environmental geology， China University of Geosciences Wuhan College of Agricultural and environmental Sciences， University of California Davis

Sedimentary microbial communities play an important role in driving biogeochemical cycles in river ecosystems. However， limited is known about the microbial variation and its influencing factors in the high-turbid Yellow River. In this study， microbial communities and their influencing factors in the sediment of upper and mid-lower reaches of the Yellow River were examined. The results showed that Gammaproteobacteria were most dominant in Yellow River sediments. Deltaproteobacteria， Nitrospirae and family of Bacillaceae， Geobaceraceae were more abundant in the mid-lower reaches， while Gammaproteobacteria， Verrucomicrobia and family of Caldilineaceae， Llumatobacteraceae were more abundant in the upper reaches. The microbial communities were predominantly affected by nutrient factors (NH4+， TN and TP)， followed by the spatial factors and Chla content in the mid-lower reaches， while they were by predominantly affected by spatial factors， followed by the nutrient factors and Chla content in the upper reaches. The dominant microbial taxa were mostly correlated with COD， NH4+， TP and temperature. In summary， the sedimentary microbial communities differ between the upper and mid-lower reaches and respond differently to the environmental and spatial factors in the sediment of the Yellow River.

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GeoChip-based microbial functions in biogeochemical cycles and their responses to environmental factors in Tengchong hot springs

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Journal of Earth Science 2024年

作者： Muhammad Inayat Ullah Khan Liuqin Huang Geng Wu Jian Yang Xiangyu Guan Hongchen Jiang School of environmental Studies， China University of Geosciences School of Ocean Sciences， China University of Geosciences Beijing state key laboratory of Biogeology and environmental geology， China University of Geosciences

Microorganisms actively participate in biogeochemical cycling processes and play a crucial role in maintaining the dynamic balance of hot spring ecosystems. However， the distribution of microbial functional genes and their influencing factors in hot springs remain largely unclear. Therefore， this study investigated the microbial functional genes and their potential for controlling biogeochemical cycles (C， N， S， and P) in the hot Springs of Tengchong， China， using the Geochip method， a functional gene microarray technology. The examined hot springs have very different microbial functional genes. A total of 22736 gene probe signals were identified， belonging to 567 functional genes and associated with 15 ecological functions， mainly involving stress response， carbon cycle， nitrogen cycle， sulfur cycle， phosphorus cycle and energy processes. The amyA， narG， dsrA and ppx genes were most abundant in carbon， nitrogen， sulfur and phosphorus cycles， respectively， and were significantly correlated with pH， temperature and SO42-. The diversity and abundance of detected gene probes were negatively correlated with temperature. The α-diversity (i.e.， Shannon index) was high at low temperature and low pH. Molecular functional interactions revealed by the gene connectivity levels were negatively correlated with temperature， pH and SO42-. These results suggested that the abundance， diversity and interactions of microbial functional genes were significantly influenced by geochemical parameters?. In addition， some genera possessed functional genes related to carbon， nitrogen， sulfur， and phosphorus cycles and can synergistically control the biogeochemical cycles of carbon， nitrogen， sulfur and phosphorus. These findings provide new insights into the functional potentials of microorganisms to participate in biogeochemical cycles and their responses to environmental factors in hot springs.

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Application status and research progress of CO2 fracturing fluid in petroleum engineering: A brief review

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Petroleum 2024年第1期10卷 1-10页

作者： Jinzhou Zhao Tong Wu Wanfen Pu Du Daijun Qingyuan Chen Bowen Chen Jintao Li Yitao Huang state key laboratory of Oil and Gas Reservoir geology and Exploitation Southwest Petroleum University Shale Gas Research Institute of PetroChina Southwest Oil & Gas Field Company

This paper comprehensively reviews the application and research progress of CO2fracturing fluids in China, highlights the existing issues and puts forward suggestions for future development. Three types of fracturing fluid systems containing CO2, namely, CO2dry fracturing fluid, CO2energized fracturing fluid,and CO2foam fracturing fluid, are categorized based on the mass ratio and process difference between CO2, water, and treatment agents. Field applications in China reveal several problem to be resolved:（1）The application scope of CO2fracturing fluids is restricted to depleted reservoirs, re-fracturing of old wells, and medium-deep reservoirs with low formation pressure coefficients;（2） different types of CO2fracturing fluids require different processes and ground supporting equipment;（3） optimization of CO2compatibility, functionality, temperature and salt tolerance, as well as the cost of treatment agents is necessitated;（4） existing CO2fracturing fluid system fail to perform well with low friction, low filtration,and high sand-carrying capacity.（5） there lacks a targeted industry standard for evaluation of performance of CO2fracturing fluid system and treatment agents. Therefore, in order to meet the goals of CCUS-EOR, CCUS-EGR, or integration of fracturing, displacement and burial by CO2, efforts should be made in the aspects that followed, including in-depth investigation of the mechanism of CO2fracturing fluids, the adaptability and compatibility between existing equipment, different CO2fracturing fluid systems and processes, and construction of treatment agents, low-density proppants and highperformance systems of recyclability and industrial-grade. In addition, optimization of CO2fracturing fluid system based fracturing design is also crucial taking such related factors such as overall reservoir geological conditions, petrophysical properties, CO2transportation, and well site layout into consideration.

关键词： Reservoir reconstruction CO 2 fracturing fluid Fracturing fluid system Fracturing displacement burial integration