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Volume 70,2024 Issue 3

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Magnetic Susceptibility Characteristics and Environmental Significance of the Last Glacial Sandstorm Deposition in Houtian Aeolian Sand Landforms

Zhong Ying, Li Zhiwen, Chen Qiong, Huang Xiaolan, Hu Haiping, Sun Li, Yang Miaowen

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Objectives: A series of sand hills formed under specific climatic conditions are widely distributed around the Poyang Lake and the lower reaches of the Ganjiang River. Aeolian sand deposits are non-zonal deposits in the subtropical region of southern China. The authors carried out many investigations on the coast of Poyang Lake in the subtropical humid monsoon climate zone, and took the aeolian sand deposition profile of Houtian Sandy Land as the research object to explore the significance of magnetic susceptibility to paleoclimate and the climate change process of the last glacial period in Houtian Sandy Land. Methods: This study carried out Optically Stimulated Luminescence (OSL) dating method, magnetic susceptibility, grain size and heavy mineral analysis of paleoaeolian sand landforms in the Houtian section of southern Poyang Lake. Results: The results of magnetic susceptibility, grain size and heavy mineral characteristics indicate that the formation environment of different sedimentary facies is different. The dune sand layer in the profile has generally low magnetic susceptibility, coarser mean grain size (Mz), lower maturity index (ZTR), and higher weathering index (HW), suggesting low weathering degree under strong winter monsoon, dry, and cold climatic conditions. On the other hand, the sandy paleosol layer exhibits higher magnetic susceptibility, finer Mz, higher ZTR index, and lower HW index, indicating lower weathering degree formed in a warm and humid climate environment with weak winter monsoon and strong summer monsoon. Additionally, the I (77.0~57.1 ka), III (49.7~36.8 ka), and V (29.7~14.9 ka) stages of the Houtian section correspond to the MIS4, MIS3 b, and MIS2 stages of deep-sea oxygen isotopes, respectively, signifying a cold period, strong winter monsoon, and low magnetic susceptibility. The II (57.1 ~ 49.7 ka) and IV (36.8 ~ 29.7 ka) stages correspond to the MIS3c and MIS3a stages, respectively, indicating a warm period with strong summer monsoon and high magnetic susceptibility. Conclusions: The climate change features contrast sharply with the record of magnetic susceptibility and mean grain size of the Weinan section on the Loess Plateau, deep-sea oxygen isotope stage and δ18O records of Chinese subtropical cave stalagmites. It can be seen that magnetic susceptibility can also effectively reveal climate change in southern aeolian sand landforms. Key words: Houtian section; aeolian sand landforms; magnetic susceptibility; heavy mineral; environmental change
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Characteristics of Key geoheritage resources and the analysis of development and utilization in Daocheng County of Sichuan Province

gaozhujun, wangdong, lizhongdong, yangjinshan, hujian, pengxiangrong

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Based on the latest data of the geological relics survey in Daocheng County and the combing of the previous survey results, the geological relics in Daocheng County are divided into 3 groups, 8 types and 17 subtypes according to the specifications. The main types are glacier landforms, water landforms, rock and soil landforms and structural profiles. It is believed that the distribution of geological relics in this area is controlled by the influence of strata and structures, which is characterized by various geomorphological landscapes, showing ' linear ' and ' agglomeration ' distribution; second, due to the influence of the' north-south high middle low ' geomorphological pattern, the distribution of geological relics is obviously controlled by altitude, and various canyon forms and glacial landforms are distributed. According to the different attributes and combination characteristics of geological relics, this paper puts forward the multi-integration of geological culture, rationally planning geological tourism products, innovating popular science propaganda methods, and paying attention to the protection and utilization of various brands, so as to provide guidance for the development of Daocheng geological relics and tourism development.
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paleoclimate and palaeoenvironment changes and their effects on dinosaur burial in the early and Middle Jurassic of Chuanjie Basin, Yunnan Province

Zhang Yaotang, Wang Wanneng

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The Jurassic greenhouse climate is an important climate warming event since Mesozoic. The global research on this event mainly focuses on marine strata, but less on continental strata. The Jurassic strata have been deposited in Chuanjie Basin in Lufeng, central Yunnan, which provides a good carrier for studying the Jurassic greenhouse climate environment. Based on the study of lithostratigraphy and trace element geochemistry of early-middle Jurassic continental red beds in Chuanjie Basin, it is considered that the climate in central Yunnan was mainly high temperature and humid in the early Jurassic, and the climate fluctuated violently and frequently in the late early Jurassic, with the lake salinity rising sharply and the temperature dropping slowly. When the middle Jurassic is about to enter, the temperature suddenly rises and the water salinity drops rapidly, resulting in the "T-OAE event". Based on the study of Jurassic dinosaur burial horizon in central Yunnan, it is found that the abrupt change horizon of climate environment in the late Early Jurassic is equivalent to this horizon, and the sedimentary and geochemical characteristics show that the cluster burial of dinosaurs is closely related to this event.
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Mesozoic Tectonic-Magmatic-Metallogenic characteristics of the Nanling-Xuancheng ore concentration district in Anhui Province and their geological significanceXU Xiaochun₁₎^,JIN Linsen₁₎^,XU Xinyue₂_⁾,XIE Qiaoqin₁₎^,XIA Cailian_¹⁾

XU Xiaochun, JIN Linsen, XU Xinyue, XIE Qiaoqin, XIA Cailian

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Nanling-Xuancheng area in Anhui province is a newly established ore concentration district in the Middle and Lower Yangtze River Metallogenic Belt (MLYRMB),and mineral exploration in this area has made important progress in recent years. Based on the results of previous regional geological surveys and the latest regional geophysical exploration and geological exploration of ore deposits,the geological and geochemical characteristics of structures,magmatic rocks and Cu-polymetallic deposits were systematically summarized,the relationship between Mesozoic region tectonism and magmatism, mineralization in the ore concentration district discussed. Research results indicate that the Nanling-Xuancheng ore concentration district is a Meso-Cenozoic continental depression-fault volcano-sedimentary basin controlled by deep faults. There are a serials of NE strike finger-like anticlinoria/thrust nappes overlapping on the basin. The stratigraphic compositions and structural characteristics of the basin-basement are basically same as those of the anticlinoria/thrust nappes, and both of them developped intrusive rocks and related Cu-polymetallic deposits with same age and characteristics. Generally the tectonic-magmatic-metallogenic characteristics of the Nanling-Xuancheng ore concentration district are consistent with other areas in the MLYRMB,indicating that since the Mesozoic era,under the control of the subduction of the Paleo-Pacific plate,the ore concentration district has experienced extreme intracontinental deformation and corresponding multi-stage NW-SE compression and extension. On the other hand,the Nanling-Xuancheng ore concentration district has its peculiarity for the characteristics of structures,intrusive rocks and Cu-polymetallic deposits of it are obviously different from those of the other volcano-sedimentary basins in MLYRMB,reflecting they have some differences in regional tectonic,crustal basement structure and composition,and rvealing that the Nanling-Xuancheng ore concentration district is the typical representative of the MLYRMB composite system of cross construction unit.
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Genetic relationship between biotite granite and beryllium-rich granite pegmatite in Ganfan Granite Body, Jiangxi Province

yangqingkun

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Abstract: The Yifeng area in the eastern part of Jiangnan Orogenic belt is an important metallogenic area for Nb, Ta, Be, Li and other rare metals in China. The ore deposits are closely related to the Mesozoic Ganfang granite body. Although the predecessors have done a lot of work on the age of Ganfang granite body, there are few studies on its genesis. In recent years, with the discovery of Be-rich granite pegmatite, the complexity of diagenesis and mineralization has been added. In this paper, LA-ICPMS U-Pb dating and geochemical analysis of biotite granite and granite pegmatite in Ganfang granite body have been carried out. The results show that the Th/U values of biotite granite zircons range from 0.11 to 0.78, and the weighted average age is 145.40±1.17 Ma. The Th/U ratio of monazite is from 6.5 to 178.4, and the weighted average age is 145.61±1.13 Ma. The 206Pb/238U age of monazite and zircon from biotite granite are consistent with the detrital zircons in the Proterozoic Shuangqiaoshan Group. The Th/U ratio of monazite of granite pegmatite ranges from 1.2 to 50.6, and the age of 206Pb/238U is relatively concentrated, with a weighted mean age of 139.51 ± 0.87 Ma. The monasites of pegmatite and biotite granite have similar EPMA data. In the different origin discriminant maps of monasite, pegmatite and biotite granite have obvious linear relationship and are distributed in the range of magmatic origin. All kinds of granites in Ganfang granite body have certain continuity in age, and the spatial interpenetration relationship can be seen successively. Its age characteristics are as follows: biotite granite → two-mica granite → Muscovite granite → lipolite Muscovite granite → beryllium-rich granite pegmatite. △FMQ of zircons of biotite granite ranges from -5.36 to -0.77, and saturation temperature (Ti) ranges from 668 to 757℃. It has the ability to form tin, tungsten and other oxidization-type metal ore with low oxygen fugacity, low temperature characteristics magma. The standardized REE partition curve of zircon chondrites shows a left-leaning partition pattern, which is consistent with the rare earth element content and partition pattern of the shell source zircon of granite. The zircon trace element diagram shows that the biotite granite has the characteristics of continental crust, S type and highly evolved granite. To sum up, the Ganfang granite pegmatite should come from the late evolutionary differentiation of biotite granite, from the partial melting of metamorphic sandstone and mudstone in Shuangqiaoshan Group.
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Structural and sedimentary evolution of the Late Cretaceous Zhengyang Basin in southeastern Chongqing, SW China

LIN Yu ) ), WANG Jun), LUO Liangdong), LI Deliang, XIONG Can) ), XIAO Ming ) ), ZHANG Saike), FANG Ruize), YANG Daifeng)

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Objectives: The Zhengyang Basin in Qianjiang, Chongqing is located in the wide spaced folds between southeastern Sichuan, Chongqing and northwestern Hunan Provinces. The Upper Cretaceous Zhengyang Formation that developed in the Zhengyang Basin is composed of two members. The first member is featured by alluvial and diluvial conglomerates, and the second member is featured by fluvial and lacustrine sandstones and siltstones, in which abundant dinosaur fossils were discovered. The basin is an intermountain basin formed the wide spaced fold belt since the Yanshanian Movement, and is ideal for studying of the Cretaceous regional tectonics of southeastern Sichuan. Detailed studies on this basin are lacking. Studies on the sedimentary sources and tectonic evolution of the basin is of great significance to reveal the Late Cretaceous tectonic evolution of southeastern Sichuan, as well as the living environment, death and mass burial mechanism of the contemporary dinosaur fauna. Methods: Based on observation, measurements and analyses on the sedimentary and structural characteristics of the Zhengyang Formation, we reevaluated the boundary fault, paleocurrent direction, sediment source and tectonic evolution history of the basin. Results: The conjugate shear joints in the basement of the basin show that the principal compressive stress σ1 is in the NW-SE direction, and the sedimentary source of of the Zhengyang Formation mainly came from the west. Conclusions: The remote effect of the Yanshanian subduction of the paleo-Pacific plate formed widely distributed joints and thrust faults in South China. Due to the continuous stress, these faults connected the detachment layers, thus the rock units stacked near the fault slope, and the anticlines spreaded and then gradually formed the wide spaced folds. In the late Yanshannian period, the normal fault "Abunjiang Fault" developed in this area with the retreat of the Pacific plate, which controlled the formation of the Zhengyang Basin with fault in the east and lapout in the west of the basin. The terrane on the west of the basin provided source materials. In the Himalayan period, this area was uplifted by local compression and denudation took place.
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Background of the South-North Water Transfer Project: Response and regulating factors of groundwater recharge to surface deformation in the middle and upper regions of the Chaobai River alluvial fan

TIAN Miaozhuang

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Continuous groundwater recharge was crucial in preventing and reducing the development of land subsidence once southern water entered Beijing in 2014. However, it is still unclear how groundwater rebound and its governing elements produce ground sinking and rebound in various places and strata. Understanding the mechanism of surface deformation, identifying the primary limiting factors for future scientific replenishment, maximizing the benefits of water resource replenishment, preventing land subsidence, and managing overexploited areas are all very important. Deep exploration and study of these relationships is also very important. This paper uses persistent scatterer interferometric synthetic aperture radar (PS-InSAR) technology, along with regional stratified groundwater level dynamic change, stratified settlement change, and other means to carry out coupling, to obtain information on ground subsidence and deformation in the study area. The intention is to determine which response and control factors between the surface and subsurface processes. The findings indicate that (1) the region"s land subsidence is slowed down by the south water"s constant replenishment, and that the Niulan Mountain region experiences surface uplift. With the rise in water level, the uplift area also gradually widens to the middle and downstream, and the maximum rebound rate reaches 46.9mm/a in 2022. (2) The Houshayu depression, which is split by the Huangzhuang-Gorliying fault, Shunyi fault, and Nankou-Sunhe fault, has undergone more alterations than other regions because for any particular characteristics of Quaternary depositional differences governed by faults. (3) The range and responsiveness of water level rise are determined by variability in groundwater level amplitude and water richness, and the direction of groundwater flow is somewhat controlled by quaternary sedimentary differences brought on by sedimentary tectonics. The findings also offer a theoretical and scientific foundation for study on mechanisms, prevention, and control of land subsidence, as well as direction and a point of reference for groundwater cleanup and program optimization that will come later.
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Thoughts on Strengthening the Overall Storage of Physical Geological Data in China

jingming, wangzengxiang

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Physical geological data is a valuable resource formed by geological exploration work. Ensuring the safe and proper storage of important physical geological data is an important guarantee for achieving effective preservation and efficient utilization of their potential value. However, how to improve the contradiction between the growing demand for important core storage and limited warehouse construction is an urgent issue facing the current work of physical geological data storage in China. The paper systematically summarizes the important achievements made in the system construction and warehouse construction of physical geological data storage in China in recent years, analyzes the main problems currently faced, and studies and proposes suggestions on the overall layout and mechanism construction of physical geological data storage in China, providing reference for improving the overall storage capacity of physical geological data in China.
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Sediment provenance and source-to-sink coupling of the late Eocene Fushan Sag in Beibuwan Basin

Liao Feiyan, Shi Yang, Zhang Yuanze, Lu Zhenghuan, Guo Hao, Li Xiaohan

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The Paleogene Fushan Sag is characterized by small area, multiple sources as well as complex and variable depositional systems, and the source-to-sink relationship and coupling are poorly understood. By multiple methods of seismic foreset reflection, zircon U-Pb dating, heavy mineral assemblage and distribution of sandstone percentage, the provenance of upper submember of the first member in Liushagang Formation was investigated to determine the source-to-sink relationship, and then different source-to-sink coupling models of the late Eocene Fushan Sag were established to guide favorable reservoir prediction. The results show that the seismic profiles from southern gentle slope, western steep slope and eastern steep slope zones exhibit obvious foreset reflection; similar to those from Hainan Island, the zircon U-Pb age spectra of Yongan and Huachang areas are characterized by double peak ages; the heavy mineral assemblages of Fushan Sag can be classified into four categories, i.e., Chaoyang area in the western steep slope zone, Jinfeng area in the eastern steep slope zone, Meitai and Yongan areas in the west side of the southern gentle slope zone, and Huachang and Bailian areas in the east side; the high percentage values of sandstone can be seen along Meitai, Huachang and Bailian areas in the southern gentle slope zone, which can be extended to Yongan area in the north, and the median percentage values of sandstone can be seen in Chaoyang area in the west and Jinfeng area in the east. Comprehensive analyses indicate that the late Eocene Fushan Sag had three major sources, i.e., Hainan Island in the south, Lingao Uplift in the west and Yunlong Uplift in the east, of which the source of Hainan Island can be divided into east and west branches. The late Eocene Fushan Sag is further divided into three secondary source-to-sink systems, including Hainan Island-southern gentle slope zone, Lingao Uplift- western steep slope zone and Yunlong Uplift-eastern steep slope zone. From the perspective of source-to-sink system, the underwater distributary channel in the source and sink system of Hainan Island-southern gentle slope zone is a favorable zone for high-quality reservoir development.
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First Discovery of Hipparion Fauna from the East Piedmont of the Taihang Mountains

Chen Shaokun, Quan Yongtao, Qi Haiyan, Zhang Tong, Pang Libo, Liu Aoran

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Objectives: The uplift of the Taihang Mountains in the late Cenozoic signals the primary formation of modern landforms in North China, but there are still many different opinions on its development. Paleontological evidence can play an essential role in the study of the uplift of the Taihang Mountains. Methods: The newly discovered Jingxing Hipparion fauna was excavated from the alluvial-fluvial fan on the Tangxian planation surface at the east piedmont of the Taihang Mountains, including Felidae gen. et sp. indet., Hyaenidae gen. et sp. indet., Dihoplus ringstroemi, Sivalhippus platyodus, Propotamochoerus sp., Chleuastochoerus sp., Schansitherium sp., Palaeotragus sp., Dorcadoryx sp., Gazella gaozhuangensis and G. cf. gaudryi. Results: The Hipparion fauna was discovered firstly in the east piedmont of the Taihang Mountains. Biochronological observation of this fauna implies an age of latest Miocene to earliest Pliocene (about 6.0-5.2 Ma) or late MN 13, correlated to Taoyang member of Gaozhuang Formation in the Yueshe Basin of Shanxi Province. Conclusions: Since the fauna was excavated from the redclay on the Tangxian planation surface, it is concluded that the uplift of this surface was not earlier than Early Pliocene. Additionally, the fauna composition indicates an open forest and grassland environment which is entirely different from nowadays.
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The discovery of terrigenous siliciclastic rocks and its significance of the Lower Permian Qixia Formation in northern Sichuan Basin

ZHANG Pengfei), LI Fengjie), LI Zhiwu), wangjia, SONG Jinmin), chenzhenan, YE Yuehao), CHEN zheng''an), zhangxihua, WANG Jia), yeyuehao

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Terrigenous siliciclastic deposits have been found in the Lower Permian Qixia Formation marine carbonate strata at the Shuanghui section, Wangcang County, northern Sichuan Basin. The provenance and depositional environment of the terrigenous siliciclastic rocks are analyzed through field section observation, sedimentology, petrology and zircon U-Pb chronology methods. On this basis, the paleogeographic pattern of the study area are reconstructed. The results show that the siliciclastic rocks has typical coastal-tidal flat depositional characteristics, which reflects that the study area experienced a transient sea level drop and exposure in the Early Qixia Stage. The morphologies of detrital zircons in sandstone indicate that they have experienced long distance transport or recycle deposition, and the U-Pb ages of zircons are mainly concentrated in the four age ranges of 2600–2400 Ma, 1800–1200 Ma, 1000–700 Ma and 500?400 Ma. Compared with the Zircon U-Pb age spectrums of the Permian, Devonian, Silurian and Precambrian strata and intrusive rocks around the Yangtze block, and integrated regional tectono-sedimentary evolution, we propose that the Siluran-Devonian strata is the possible source of the Permian siliciclastic rocks. The zircon age frequency spectrum of the Qixia Formation siliciclastic rocks is very similar to those of Liangshan Formation, which indicates that the Liangshan Formation is probably the direct material source of the siliciclastic rocks. The occurrence of siliciclastic rocks indicates that there existed short-lived island or old land in the local area of the northern Upper Yangtze, which provided a favorable depositional environment and source supply for the formation of siliciclastic rocks. Based on the sedimentary characteristics and provenance analysis of the siliciclastic rocks, a multi-stage Early Permian paleogeographic evolution model in the northern Sichuan Basin is established. The discovery of the terrigenous siliciclastic rocks of the Qixia Formation is of great significance for the deep understanding of the Early Permian paleogeographic pattern, tectono-sedimentary evolution and hydrocarbon exploration in the northern Upper Yangtze region.
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Zircon SHRIMP U-Pb Ages and Hf Isotope Characterestics and Their Geological Significance of Tuff in Ordovician Majiagou Formation in the Middle-eastern Ordos Basin

Wu Haowen, Su Zhongtang

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The Upper Member of the Ordovician Majiagou Formation (referred to as the "M5" member) in the Ordos Basin is characterized by the presence of two layers of tuffs, which are commonly used as regional marker beds for stratigraphic correlation. Investigation of the zircon ages of these tuffs can help establish the chronostratigraphic framework of the Majiagou Formation and provide insights into its depositional period and tectonic background. Zircon SHRIMP U-Pb dating and Hf isotope analysis were conducted on tuffs from wells S148 and T56 in the M5 member of the basin. The obtained zircon ages of these two samples are 458.4±2.4 Ma and 460.9±2.9 Ma, respectively. Based on these results, the deposition of the Majiagou Formation is constrained to the Middle Ordovician Darriwilian to Upper Ordovician Sandbian stages. The measured n(176Hf)/n(177Hf) ratios of in-situ zircon Hf isotopes range from 0.282687 to 0.280820, and εHf(t) values vary from +6.67 to +11.32, with two-stage model ages ranging from 720 to 1024 Ma. Comparison of the zircon U-Pb ages and Hf isotope characteristics of the tuffs surrounding the basin suggests that the volcanic tuffs of the Majiagou Formation may have originated from the North Qinling and/or North Qilian orogenic belts in the southwestern part of the basin. Furthermore, it is inferred that prior to the emplacement of the tuffs, the North Qinling and/or North Qilian Ocean initiated a northward subduction and entered a stage of ocean-land transition, indicating the transformation of the western and southern margins of the basin into an active continental margin during the Late Middle Ordovician.
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Geochemical characteristics of Lower Cretaceous in Zhenyuan area of Ordos Basin and its indication to provenance and tectonic setting

HE Zhongbo, HU Baoqun, JI Huali, HE Feng, GENG Yingying, HUANG Shaohua, ZHU Manhuai

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Based on the geochemical analysis of major elements, trace elements and rare earth elements（REE）of the Lower Cretaceous sandstone in Zhenyuan area of Ordos Basin, this paper discusses the sedimentary recycling characteristics, chemical weathering, tectonic background and material source of the Lower Cretaceous red variegated sandstone. The results show，（1）The Lower Cretaceous Luohe Formation, Huanhe Formation and Luohandong Formation are similar in provenance main body, and have good inheritance in structural background, provenance area and provenance characteristics. The provenance area is generally characterized by rich quartz, rich Calcite cement, more potassium feldspar or potassium rich minerals than plagioclase. The Luohandong Formation is more siliceous than Huanhe Formation and Luohe Formation, with less Calcite cement and purer quality. The REE distribution pattern curves of rare earth elements are consistent, with clear fractionation of light and heavy rare earth elements, enriched in large ion lithophile elements Ba, Pb, Sr, and light rare earth elements, and depleted in high field strength elements Nb, Ta, Th, Y, etc. From bottom to top, with the formation becoming newer, the total REE content in Sedimentary rock tends to decrease, and the fractionation degree of heavy REE decreases.（2）The original material of the Lower Cretaceous sandstone in the study area is mainly composed of felsic and mafic mixed rocks（such as intermediate-acid intrusive rocks, felsic metamorphic rocks）and some sedimentary rocks. Most of the sediments in the study area are transported by the weathering and denudation products of the parent rock in the thrust nappe zone on the southestern margin of the Ordos Basin, Which are the first sedimentary materials. A few sediments ( i.e., Aeolian sand) are formed by in-situ re-transport and accumulation, which are recycled sedimentary materials. （3）In the tectonic setting, the passive continental margin tectonic environment is the main advantage. The debris mainly comes from the continental source area, followed by the recycled orogenic belt and the mixed source area.
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Sedimentary Characteristics of Lower Cretaceous in Wuerhe-Huanghuagou area, northwestern margin of Junggar Basin

JI Huli, HE Zhongbo, ZHONG Jun, CHEN Hong, ZHU Bin, WU Yu, DONG Qian, GENG Yingying

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Based on the comprehensive analysis of outcrops, drilling cores, drilling and logging in the Wuerhe-Huanghuagou area on the northwestern margin of the Junggar Basin, combined with microscopic observation, the main petrological characteristics, stratigraphic structure, sedimentary facies types and distribution characteristics of the Lower Cretaceous Tugulu Group were comprehensively analyzed. Guided by the metallogenic theory of sandstone-type uranium deposits, the types and distribution of favorable ore-forming sand bodies in the Lower Cretaceous Tugulu Group in the study area were discussed from the perspective of sedimentology. The results showed：(1)The rock types of the Lower Cretaceous Tugulu a sub-group in the study area are mainly feldspar lithic sandstone and lithic feldspar sandstone, while the Tugulu b, c and d sub-groups are mainly feldspar sandstone and feldspar lithic sandstone.(2)There are four types of sedimentary facies in the Lower Cretaceous Tugulu Group in the study area, which are alluvial fan, braided river, delta and lake. With the Delun Mt. as the boundary, the Wuerhe-Xiazijie area is dominated by shallow-water delta deposits with far-source weak current, while the Delun Mt.-Huanghuagou area is dominated by high-energy braided river deposits.(3)The favorable prospecting horizon of the Lower Cretaceous is the primary gray-gray green coarse clastic formation of the Tugulu a + b subgroup. The branch channel of delta plain subfacies in Wuerhe-Youshashan area is an important prospecting direction. The underwater distributary channel of delta front and the thick sand body of sheet sand widely developed in the Xiazijie area have good lateral extensibility, and have the structure of " mud-sand-mud ". Under the condition of sufficient supply of water source, uranium source and oxygen source, it has the ability to form a certain scale sandstone-type uranium deposit.
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Development Sequence, Formation Age and Geological Significance of Piedmont River terrace in Pinggu, Beijing

Wang Xiaoliang, Zhao Yuanyi, Zhao Xitao, Chen Jundian, Wu Wenbin

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River terrace is a good carrier for the study of river evolution and tectonic movement. Although the Quaternary geology in Beijing area is highly studied, there are few relevant research data on river terrace in the east of Beijing. In this paper, Ju River, Huangsongyu River and Jiangjunguanshi River developed in front of Yanshan Mountain, are taken as the research objects in Pinggu Beijing. The development sequence of the above-mentioned river terraces is divided in detail. On this basis, the formation times, terrace genesis and the response of river terraces to the uplift of Yanshan Mountain are discussed by field geological survey and opto-luminescence dating (OSL). It is considered that Ju River developed three terraces on the south bank and developed two terraces on the north bank. Huangsongyushi River developed six terraces. Jiangjunguanshi River developed five terraces. Jiangjunguanshi River was formed at least in the late Middle Pleistocene (161.7±7.7 ka BP) and Huangsongyushi River was formed at least in the early late Pleistocene (121.2±5.4 ka BP~100.3±4.1 ka BP). Ju River was formed at least during the middle of the Late Pleistocene (79.4±3.3 ka BP to 70.8±3.4ka BP). The formation of the terraces of Ju River, Huangsongyu River and Junjiangguanshi River is influenced by paleoclimate change and Yanshan Mountains uplift. Yanshan Mountains in Pinggu area has been in a state of uplift since the late Middle Pleistocene, and the uplift rate reached the maximum in the early late Pleistocene, up to 0.24~0.34 mm/a, and decreased in the middle of the late Pleistocene. 0.18 to 0.24 mm/a. The above results have important reference value for the study of the development characteristics and formation times of river terraces in eastern Beijing, and also provide new evidence for the uplift of Yanshan Mountain since the late Middle Pleistocene.
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Geochemical characteristics of Wufeng-Longmaxi shales in the southern margin of the Upper Yangtze and their implications for weathering, provenance and tectonic setting

Qin He Xing, chen lei, lu chang, hu yue, xiong min, tan xiu cheng, ji yubing, chen xin, wang gao xiang

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Objective: In order to further explore the material source, weathering and tectonic setting of the Late Ordovician-Early Silurian black shale in the southern margin of the Upper Yangtz, this study selected typical field section for systematic sampling, systematically studies the geochemical characteristics of major, trace and rare earth elements of Wufeng-Longmaxi Formation shale and discusses its geological significance. Methods: Through the characteristics of major, trace and rare earth elements of 22 samples of Wufeng-Longmaxi Formation shale in the field profile of the southern margin of the Upper Yangtze, the ancient weathering intensity and paleoclimate conditions were restored, the source rock properties and tectonic background were revealed, and the shale formation environment and process were explored, which provided more favorable geochemical evidence for further exploration and development of Wufeng-Longmaxi Formation shale in the Upper Yangtze region. Results: The black organic-rich shale of Wufeng-Longmaxi Formation in the southern margin of the Upper Yangtze has the characteristics of poor high field strength elements and enrichment of large ion lithophile elements similar to the upper crust. The ∑ REE value (103.66×10-6~295.98×10-6, average 180.57×10-6) is generally high. The standardized distribution pattern of rare earth elements is very similar to that of the upper crust, showing the characteristics of 'V' type to the right, enrichment of light rare earth elements, flat heavy rare earth elements, obvious differentiation of light and heavy rare earth elements, and obvious negative Eu anomaly. The contents and ratios of characteristic trace and rare earth elements, such as La, Ce, La/Yb and Sc/Cr, are close to the characteristic values of passive continental margin. The ICV values (0.55~14.1, average 2.28) and Zr/Sc- versus Th/Sc diagram indicate that the source is the first rapid sedimentary product of the tectonic belt, and does not have the characteristics of sedimentary recycling. The lower CIA value (54.89-71.61, average 65.27), A-CN-K diagram and K2O/Al2O3 versus Ga/Rb diagram indicated that the provenance was less affected by chemical weathering, and the sedimentary environment was cold and dry. The high contents of K2O, Rb, Al2O3/TiO2 and negative Eu anomaly indicate that the source rocks are dominated by felsic igneous rocks and acidic geological bodies of granites. Conclusion: Based on the discriminant diagram of provenance and tectonic background, it is inferred that the main body of Wufeng-Longmaxi Formation shale in the southern margin of Upper Yangtze is formed in the passive continental margin. The provenance mainly comes from the early Neoproterozoic platform caprock of Kangdian ancient land on the west side, followed by Qianzhong uplift, with the influx of intermediate-acid volcanic materials in the southeast of Yangtze plate.
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Characteristics of Ordovician paleokarst development and paleogeomorphic restoration in Shungeng mountain, Huainan

YANG Tingting, XU Guangquan, ZHANG Zhu, LI Hao, ZHANG Jinsheng, HE Biao

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s: The characteristics of paleokarst development and the restoration of paleomorphology are important for preventing and controlling karst water damage in the North China Coalfield. This study focuses on the paleokarst of the Ordovician system in Shungeng Mountain, Huainan area, which is located at the southern edge of the North China plate. The characteristics of paleokarst development and the bedrock is undulating were revealed by field geological surveys, sectional profiling and residual thickness methods. Based on modern karst theory, the spatial variation patterns of different karst zones were analyzed from the perspective of their formation conditions, and the paleokarst landforms were restored. The results show that the Majiagou Formation has mainly large karst channels and holes with little internal filling, while the Xiaoxian Formation has mostly interlayer karst along the level, filled with karst breccias. The internal filling calcite increases from east to west. The Ordovician palaeokarsts in the Shungeng Mountains weaken gradually from east to west and from top to bottom. The Ordovician paleomorphology of the area is higher in the east and lower in the west and can be divided into four three-level karst geomorphic units: residual hills, gentle slopes, steep slopes and depressions. The paleokarst landscape from top to bottom was classified into superficial karst zone, vertical seepage zone, horizontal submerged flow zone and deep slow flow zone from shallow to deep, based on the karst geological conditions, groundwater runoff patterns and karst development characteristics. The superficial karst zones and vertical seepage zones of the residual hills and gentle slopes are the most developed, and large karst fissures often occur between the sedimentary layers, which may cause karst collapses when the groundwater flow changes.
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Modern piedmont sediments of the Altyn Tagh in northern margin of the Qinghai-Tibet Plateau: Petrological research of lithic fragment in the Kumtagh Desert

JIN Bingfu, wubo, zhang yunji, yu jian, HASI Eerdun, Su Zhizhu, KONG Deyong, LI Xiubin, wu

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The Gobi, platform, terrace, flat sand land on the edge of the Kumtagh Desert, as well as the interdune and gravel bodies inside the desert are rich in gravel of different sizes. The feathery flowing dune in the central and northern part of the desert core contains more coarse sand, which is rock debris rather than mineral debris. As a temporary intermediate product of weathering of parent rock, lithic fragments are the most reliable and direct indicator of the nature and origin of parent rock. In this study, the coarse grained rock deposits in the Kumtagh Desert were quantitatively analyzed by using the lithology microscopic identification and statistical methods of sand flakes for the first time of the desert research history. The results show that the types of fine gravel and coarse sand rocks in the Kumtagh Desert are very complex, including three rock classes(igneous rock, metamorphic rock and sedimentary rock), 14 rock classes and more than 100 subclasses, which are mainly middle-acid effusive rocks and regional metamorphic rocks. The most common lithologies are rhyolite, felsite, andesite, trachyte, quartzite and quartzitic rock. The lithology of dark particles is mainly middle-acid effusive rocks, while the lithology of light particles is metamorphic rocks and felsic minerals. The quartz fragments have both light and dark colors, which reflects the diversity of genesis and sources. The lithology of the debris is closely related to the grain size of the sand, the grain size of the sand is coarse, the lithology of the rock debris is relatively common with large mineral grains, while the content of the rock debris with fine grain size and the lithology of the parent rock with small mineral grains will increase, and at the same time, the content of single mineral in the sand will increase exponentially. This law makes different regions and different geomorphic locations of the desert, because of the different grain size of the sand. Regional differences of lithology distribution appear. The lithology in the desert is almost exactly the same as the lithology in the Altyn Tagh Mountain. The desert contains not only the common dynamic metamorphic rocks in the Altyn Tagh Mountain, but also various rock types of the ophiolite hybrid series unique to the Hongliugou - Lapaiquan member of the Altyn Tagh Mountain, which fully indicates that the gravel and coarse sand in the Kumtagh Desert come from the weathering of the parent rock of the Altyn Tagh Mountain. The difference of weathering of parent rocks and the different historical stages of mountain uplift make the content of lithology in desert different from that of mountain parent rocks. The cryptocrystalline and fine crystalline rocks resistant to weathering become the main characters of desert sand debris. The granitic rocks and mid-deep metamorphic rocks with coarse grained (crystalline) structure are easier to be decomposed into single minerals and are the main material sources of desert fine sand.
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Multiple phases of continental crustal growth of the basement of the Yanliao intracontinental rift: Constraint on the detrital zircon U-Pb-Hf isotopes of the sediments of Changcheng Group

LiWenqi, Liu Huichuan, Liu Xiaoping, Yu Zhiqi, Wang Yiren, Wang Yingying

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The continental crustal growth of the North China Craton has been extensively studied. However, there has been limited discussions regarding the crustal growth of the Yanshan-Liaoning Rift Basin, which is covered by thick sediments. In this study, we focuse on sedimentary rocks of the Changcheng Group overling the Yanliao intracontinental rift and investigate scientific issues such as sedimentary age, provenance of detrital zircons and crustal growth events by analyzing the age spectrum and Lu-Hf isotope data of detrital zircons of the sediments within the Changcheng Group of the Yanliao intracontinental rift. U-Pb isotopic ages constrain the timing of initiation of the Yanliao rift as ca. 1680 Ma. The zircon U-Pb data show two major age populations at 2.7–2.5 Ga and 2.2–1.9 Ga, with high and positive eHf(t) values of + 0.1 to + 34.6. By comparing the U-Pb dating, Lu-Hf isotope εHf(t) and TDM2 model age data of detrital zircons from the Changcheng Group with those of the crystalline basement in the North China Craton, it can be inferred that the sedimentary source of the Changcheng Sediments in the Yanliao intracontinental rift originated from the underlying basement of the Yanliao intracontinental rift. Based on the comprehensive analysis of detrital zircon U-Pb dating, εHf(t) values, and TDM2 model age data, it is suggested that the North China Craton experienced three peaks in its Mesoproterozoic pre-crustal growth history, which occurred at approximately 2.7–2.5 Ga, 2.2–1.9 Ga and 1.7–1.6 Ga.
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Review on short polarity reversal events during the Cretaceous Normal Superchron

ZHANG Dawen

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The Cretaceous Quiet Zone, also known as the Cretaceous Normal Superchron (CNS, 121.4~83.6 Myr), represents the most extreme geomagnetic field behavior in the geological history. Study of the characteristics of the geomagnetic field during the CNS is of great significance for understanding the abnormal changes of the physical and chemical processes in the Earth’s interior, such as the movement of the outer core fluid, the heat flux regime across the core-mantle boundary and patterns of mantle convection. Therefore, this paper systematically reviewed and summarized the previous research work related to short reversed-polarity events during CNS from the perspective of polarity reversal. The following main conclusions and views are obtained: the marine sediments, volcanic rocks and terrestrial sediments together indicates that at least seven reported reversed-polarity events or clusters of events might have happened within the CNS, including the Middle-Late Aptian (M“-1r” or “ISEA”), Late Aptian-Early Albian (~113.3 Myr), Middle Albian (M“-2r” set?), Late Albian (M“-3r” set?), Late Cenomanian (~96 Myr), Late Turonian and Late Coniacian-Early Santonian, which presents global synchroneity and a periodicity of 4~6 Myr. However, given the problems and uncertainties in paleomagnetic sampling and measurement methods, stratigraphic dating, possible remagnetization and rock magnetic analysis, the authenticity of polarity reversal events during the CNS and their occurrence time, frequency and duration are still controversial. Meanwhile, the short reversed-polarity events as a new constraint condition for the numerical simulation of the geodynamo can contribute to more scientifically revealing the unique dynamic change process in the Earth’s interior during the CNS and the internal genetic relationship with the global geologic events in the mid-Cretaceous. In the future, the integrated high-resolution magnetostratigraphic and geochronologic researches in the Cretaceous long-term scale, as well as the fine rock magnetic analyses of the reversed-polarity zones, is the key to accurately constrain the occurrence regularity of short polarity reversal events during the CNS.
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Renjiatan-Qiaomaishan potassic intrusive rocks in the southern margin of North China : Petrogenesis and its implications for the late Paleoproterozoic breakup

LIYi, LI Zuochen, ZHAO Duangchang, ZHAO Pengbin, LV Junli, ZHANG Yafeng

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In the southern margin of North China Craton, a series of alkaline rocks of 1.8 ~ 1.6 Ga were found in Luonan, Shaanxi Province, and the west area of Henan Province. The study of these alkaline rocks can facilitate the understanding of the Paleoproterozoic tectonic environment of the southern margin of the North China Craton. This paper systematically studied the potassic alkaline intrusive rocks in the Renjiatan-Qiaomaishan area in Luonan County, Shaanxi Province in terms of petrology, LA-ICP-MS zirconium U-Pb geochronology, Lu-Hf isotope analysis, and petrogeochemistry and discussed their genetic mechanism and tectonic setting. The results show that the main lithology of the rock mass in the Renjiatan-Qiaomaishan area is syenite porphyry, with a weighted average age of 1689 ± 20 Ma ( MSWD=0.12 ), which indicates that the emplacement of the rock mass happened in the Paleoproterozoic area. The rock mass is rich in alkali ( Na2O+K2O=7.95% ~ 9.5% ) and high in potassium ( K2O=4.67% ~ 8.51% ). The total amount of rare earth elements is high ( 496.15×10-6 ~ 650.16×10-6，average 543.06×10-6 ) , and the fractionation of light ( LREE=454×10-6 ~ 605×10-6 ) and heavy rare earth elements is obvious ( HREE=39.3×10-6 ~ 45.6×10-6 ). The light rare earth elements are relatively rich, while the heavy rare earth elements are deficient, and there is a weak negative europium anomaly. In addition, K , Rb , Ba , Th is rich, while Nb , Ta , P , Ti is deficient, and there is an obvious negative Sr anomaly. The value of εHf ( t ) is less than 0, the value of TDM1 is 2038 ~ 2218 Ma and TDM2 is 2250 ~ 2516 Ma , indicating that the materials in the magmatic source area are related to the enriched mantle or contaminated by the crustal materials. Therefore, the rock mass in the Renjiatan-Qiaomaishan area is a melt formed by mixing the basaltic magma of the mantle with the medium-acid granitic magma formed by the Taihua complex TTG crust. It was formed in the tectonic environment of an intracontinental rift through strong crystallization differentiation, reflecting a response of the southern margin of the North China Craton to the cracking event of the Columbia supercontinent.
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Petrogenesis of Fuling A- type granite in the southern Anhui Province：Constraints from petrogeochemistry , Zircon U-Pb age and Lu-Hf isotope characters

zhengwei, chentianhu, dujianguo, chenfang, dingning, zhangshu

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Objectives: The Fuling pluton is a granitic body located in the adjacent area of Anhui and Zhejiang provinces in the eastern section of the Jiangnan orogenic belt. The magmatic rocks are distributed along the Ningguo-Jixi deep fault extending near the NE direction. The research work on the Yulongchuan (γ53 (2) )unit granite in Fuling Pluton has been carried out in this paper. Methods: Based on the field work, we finished microscope observation, whole-rock geochemical analysis, LA-ICP-MS zircon U-Pb dating and in situ Lu-Hf isotope geochemistryfor the Yulongchuan (γ53 (2) ) unit granite. Results: The LA-ICP-MS zircon U-Pb dating shows that the emplaced age of the granite is 131.75±0.91Ma, which is the product of magmatic activity in the late stage of the Jiangnan orogenic belt. The pluton is rich in silica and alkali, and poor in calcium and iron. The characteristics of trace elements show that there are higher Rb, Th, U, Ga, Zr and Y contents, and there are lower Sr , Ba and Nb. The rare earth partition curve presents a typical "seagull" distribution, showing strong negative Eu anomalies. Negative anomalies of Ba, Sr and Nb are found in the primitive normalized mantle spider map of trace elements. The zircon εHf (t) of Fuling granite varies from -7.0 to -4.6, and the two-stage model age (TDM2) ranges from 1478 to 1630Ma. The Th/U values, Th/Nb values and Th/La values are all higher than the average continental crust value, and the La/Nb values is slightly lower than the average continental crust value. Conclusions: The high SiO2 content, Rb/Sr value and low Ba and Sr content show that the Fuling granite has the typical characteristics of the A-type granite in the eastern part of Jiangnan orogenic belt, southern Anhui Province. The Fuling pluton has the characteristics of homologous magmatic evolution, and the separation and crystallization of apatite and ilmenite minerals may exist in the source area, while the separation of pyroxene minerals is less. The source rocks of Fuling pluton are mainly derived from partial melting of mafic rocks in the crust, and their geochemical characteristics are inherited from the source rocks. The Fuling granite may have been formed by partial melting of the ancient lower crust in Mesoproterozoic, and its source material is mainly the ancient lower crust. The positive δEu anomaly of Fuling pluton and the high Sr content of some samples indicate that the magma source is deep. These geochemical characteristics all indicate that the formation of Fuling granite may have been mixed with mantle materials.The formation of Fuling pluton may be influenced by collision. The rock mass was formed in post-collision. Asthenosphere upwelling led to the melting of the subcontinental lithosphere mantle, which produced a large number of new basaltic magma. Thus, Fuling A-type granite is produced.
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Formation age, geochemical characteristics and tectonic significance of Biqigenao pluton

ZHANG Jianchao, ZHU Kongyang, YANG Bo, SU Meixia, XU Liquan, ZHOU Fei, DONG Chuanwan, SHEN Zhongyue, WU Yanjun, MENG Xiaoling, She Linlin

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The Biqigenao pluton is composed of two phases of intrusions, the lithology of which is granodiorite and monzogranite, the former being the main lithology of the pluton. Granodiorite is mainly composed of plagioclase (An = 15 – 30), quartz, alkali feldspar and amphibole, with mafic microgranular enclave inside; The monzogranite is mainly composed of quartz, alkali feldspar and plagioclase (An = 10 – 20). Zircon U-Pb dating shows that the pluton was formed in the Late Permian, and its formation age is 259 Ma. The main granodiorite with SiO2 = 66.37% – 68.70% is aluminous-weakly peraluminous (A / CNK = 0.99 – 1.01), which is characterized by enrichment of light rare earth and large ion lithophile elements, depletion of heavy rare earth and high field strength elements, belongs to I-type granite; mafic microgranular enclave is rounded or elongated flat lenticular, and the age is consistent with the granodiorite, which is the product of magma mixing; Monzogranite is high silica granite (SiO2 = 71.51% – 73.09%), alkali-rich (Na2O + K2O = 7.91% – 8.61%) and weakly peraluminous to strongly peraluminous (A / CNK=1.07 – 1.11), is a differentiated I-type granite. The εHf (t) of Ziron distribution range is ? 3.0 – 3.4, and the corresponding Hf isotope two-stage model age is 1473 – 1057Ma. It has relatively low (87Sr/86Sr) i value (0.704829 – 0.705327), ε Nd (t) value is ? 5.85 – ? 8.86, and the corresponding Nd two-stage model age is 1.69 – 1.45 Ga. Based on the regional research data, it is considered that the Biqigenao pluton is formed by mixing the depleted mantle component with the partially melted ancient crustal material induced by it, and belongs to the post-collisional granite.
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Deposition time and tectonic background of Baoshuping Formation，Erlangping Group in North Qinling

zhaiwenjian, zhangyong, tangguosheng, zhaohuan, zhaiwenfang

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The Baoshuping Formation of the Erlangping Group is an important Early Paleozoic sedimentary record in the North Qinling, but it has been relatively under-studied. This study aims to further determine its depositional age and tectonic environment through petrological, geochemical, and zircon U-Pb dating investigations of volcanic interbeds and granite veins within the Baoshuping Formation. The research results indicate that the lithology of the volcanic interbeds of the Baoshuping Formation in the Xiaguan area of western Henan Province is biotite actinolite sodium schists, often interbedded with biotite quartz schists. The protolith of the rocks is andesitic tuff, characterized by relatively low SiO2 (52.56%–62.04%), relatively high Al2O3 (10.70%–18.55%), low MgO (4.06%–6.21%) and FeOT/MgO (1.23–1.81). It is enriched in light rare earth elements (LREEs)and large ion lithophile elements (LILEs, Rb, Th, U, K), and relatively depleted in high field strength elements(HFSEs, Nb, Ta, P, Ti), exhibiting characteristics of magnesian andesite rocks. Based on geochemical characteristics and previous studies, it is inferred that the Baoshuping Formation may have formed in an active continental margin back-arc basin. The crystallization age of the protolith of biotite actinolite sodium schists obtained by U-Pb dating of zircon is 446.0±1.7 Ma, and the crystallization age of the intrusive granite porphyry is 430.0±3.0 Ma, accurately dating the formation age of the Baoshuping Formation as Late Ordovician to Early Silurian for the first time. Integrated regional research results suggest that the Xiaozhai Formation and Baoshuping Formation conform to the division scheme of the generalized Erlangping Group in terms of stratigraphic sequence and stratigraphic age. However, the Damiao Formation, Huoshenmiao Formation, and the composite of the Xiaozhai Formation and Baoshuping Formation exhibit near-simultaneity in formation age and a nearly parallel spatial relationship, indicating that they are likely products of different depositional environments with roughly equivalent ages. In terms of tectonic attributes, it is believed that Erlangping Group formed as a volcanic island arc due to the northward subduction of the Shangdan Ocean before approximately 470 Ma, transformed into a back-arc basin between 470 and 436 Ma, and completed the subduction closure process before approximately 430 Ma.
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Characteristics of strike-slip transfer zone and its control on large-scale reservoir of buried hill in Liaobei area, Bohai sea

Hui Guanzhou, NIU Chegnmin, YANG Chuanchao, ZHANG Jiangtao, GUAN Chao, WANG Mingchun, ZHAO Jing

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The buried hill strike-slip transfer zone is widely developed in the Bohai Sea area, but its development characteristics and reservoir control are weak. Based on drilling, logging, 3D seismic and other data, the development characteristics, genetic mechanism of structural transfer zone and their control effect on buried hill scale reservoirs in northern Liaodong Bay are analyzed. Study shows that under the background of sinistral strike-slip at the late Yanshan, many types of transfer zones are developed in buried hills in northern Liaodong Bay; According to the interaction of strike-slip faults and the shape of the tranfser zone, the buried hill transfer zone in northern Liaodong Bay can be divided into two types: single-branch bending type and double-branch overlapping type; According to the local stress state, it can be further subdivided into four subclasses: singl-branch anti "s" type, single-branch "s" type, double-branch left-handed right-order and double-branch left-handed left-order transfer zones. Among them, single branch anti "s" type and double branch left-handed right-order transfer zones belong to pressurized transfer zones, and single branch "s" type and double branch left-handed left-order transfer zones belong to pressure relief transfer zones; The compressive torsional dynamic crushing provided by the pressurized transfer zone makes the buried hill develop large-scale fractured reservoir, which is the key to the development of large-scale buried hill reservoir.
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A review of the application of deformation measurement methods in geomechanical model experiments

SU Zhandong, WANG Zhiwen, SUN Jinzhong, ZHANG Jianyong, LIANG Jinping, NIU Yao, ZHANG Zhitai, ZENG Yangnong, LI Mengyuan

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As a convenient, efficient and low-cost research method, geomechanical model experiment can not only present the failure process of engineering intuitively, but also serve as an important research means to understand the overall mechanical characteristics, failure mode and stability of engineering. Therefore, geomechanical model experiments are widely used in the study of various geotechnical engineering problems. Due to the low deformation modulus of geomechanical model materials and their extremely sensitive strain under the same stress conditions, deformation measurement is crucial in model experiments. In order to improve the convenience and accuracy of deformation measurement in geomechanical model experiments, the main methods of deformation measurement in the current geomechanical model are summarized and analyzed. The results indicate that currently, the methods for measuring model deformation mainly include electrical measurement method, optical measurement method, and mechanical measurement method. Among them, electrical measurement method mainly includes resistance strain gauge method and displacement meter method, optical measurement method mainly includes fiber optic sensor method, digital image correlation method, photoelastic patch method, and moire interferometry method, and mechanical measurement method mainly includes percentage meter measurement method and theodolite observation method, through the explanation and comparison of the working principle, main application cases and advantages and disadvantages of various methods. The main difference between the different methods is the difference in the measurement range and the scope of application, among which the percentile meter method is suitable for measuring the deformation of a small area; To measure the internal deformation, the resistive strain gauge method and optical fiber sensor method can be selected; For deformation in larger areas, the displacement meter method and the optical fiber sensor method can be selected; The theodolite observation method can be selected for the specified point displacement; For full-field observation, digital image correlation method, cloud interferometry and photoelastic patch method can be selected. This achievement can provide an experimental reference for the experimental deformation measurement of related geomechanical models.
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Evaluation method and application of crude oil cracking gas resources — taking the Sinian-Cambrian of Sichuan basin as an example

GUO Zeqing, ZHAO Wenzhi, XIE Zengye, WANG Zhihong, Jiang Hua, LI Jian, ZHU Guangyou

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The Sinian-Cambrian natural gas resources are abundant in Sichuan basin. In recent years, two giantSgas-accumulatingSareas with trillion cubic meters reserves have been discovered in the central Sichuan palaeo-uplift and northern slope areas of the Sichuan Basin. However, the specific scale of resources and the future exploration direction in this field are still unclear. In this study, based on the basic understanding that the natural gas in this area came from the cracking of crude oil in ancient oil reservoirs, the resource amount of crude oil cracking gas was calculated according to the technical route of kerogen generating oil and then cracking gas from ancient oil reservoirs. The formation thickness maps, lithofacies palaeogeography maps, comprehensive evaluation maps of hydrocarbon source rock, erosion thickness maps and oil generation dynamics parameter plates were inputted to PetroMod 3D basin simulation software, and the 3D geological model was established to calculate oil generation in five primary tectonic units and restore the oil generation history, and the critical moment of ancient oil reservoir formation was clarified. Then, the oil migration and accumulation coefficient, oil cracking rate, gas loss rate and the partition coefficient of Cambrian oil migration were discussed, and the calculation formula of natural gas loss coefficient was established. Finally, the conventional natural gas resources of the Sinian and Cambrian in the whole basin are 13.43 trillion cubic meters, including 5.43 trillion cubic meters in Cambrian and 8.0 trillion cubic meters in Sinian. It is also pointed out that apart from central Sichuan, southern and eastern Sichuan have great exploration potential, especially the platform margin zone and intra-platform granular beach located on both sides of Deyang-Anyue rift in southern Sichuan are the practical areas for further exploration. On the one hand, this study provides a set of practical and feasible evaluation methods for the crude oil cracking gas resources; On the other hand, it has implemented the resource potential of the natural gas of the Sinian - Cambrian system in Sichuan Basin and strengthened the exploration confidence. This study is of great significance in theoretical innovation and exploration practice.
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Statistics and analysis of basalt fiber raw material characteristics

LiZhen, XU Guanli, LIU Rong, SHI Kaiwen

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Basalt fiber is a kind of high-performance fiber manufactured by melting and drawing from basalt or rocks of similar composition. Fluctuation in the composition of natural rocks can cause difficulties in drawing and instability of fiber properties. This paper collected data on the chemical composition of 54 groups of raw rock and 114 groups of basalt fiber samples. The petrological, parameter index and other characteristics of the raw material needed for basalt fiber were summarized, and the optimal range of related parameter indexes of raw materials were proposed. The characteristics of raw rock which is suitable for the production of basalt fiber can be summarized as follows: from the perspective of petrology, basic rocks or intermediate rock with a SiO2 content of 53% to 57% are the optimal; the most suitable rock type is basalt or andesite; the most appropriate rock texture is intersertal texture, vitrophyric texture or hyaline texture. The influence of structure is indirect, mainly due to some adverse minerals which may be contained in fumarolic structure or amygdaloidal structure. From the perspective of mineral composition, hydrous minerals such as serpentine and zeolite will cause bubbles in the melt, which will affect the continuity of fiber preparation but will be conducive to the full melting of raw materials. High melting point minerals such as forsterite and magnetite will make it difficult for raw materials to melt completely, resulting in uneven melt and easy crystallization. From the perspective of parameter index, the optimal range of acidity coefficient (Mk) is 4.0 to 5.5. The viscosity coefficient (Mv) is 2.0 to 3.0. The ratio of silicon aluminum oxides to other oxides is 1.5~3.0. The molar fractions of oxides are n(RO) = 20% to 30%, n(RO2) = 57% to 70%, and n(R2O3) = 10% to 16% (R stands for cations).
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Geochronology, geochemistry and geological implications of the Early Paleozoic intermediate-basic complex in the upper reaches of Pangu river of the northern Great Xing’an Range

LI QIANG, CHENG Xueqin, WANG Yankai, LI Zhimin, LIU Hongzhang, YANG Ning, SHEN Jinqing, LUO Shanxia

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The origin, source characteristics and dynamic background of the Early Paleozoic magmatic rocks in the Erguna massif are of great significance for revealing the tectonic evolution history of the restoration area. In this paper, the Early Paleozoic intermediate-basic complex in the upper reaches of Pangu River in the Northern of Great Xing’an Range was selected for petrology and zircon U-Pb chronology and petrogeochemical analysis. Field investigation and laboratory study show that the rock types of the complex are mainly hornblende gabbro and gabbro, rare quartz diorite, diorite, pyroxenite, olivine gabbro and other intermediate rocks or ultrabasic rocks. The dating results show that the formation age of the hornblende gabbro is 479.2±2.1Ma, indicating that the complex was formed in the Early Ordovician. In terms of geochemical composition, the Early Paleozoic intermediate-basic complex rocks in the upper reaches of the Pangoo River have SiO2 contents ranging from 40.74% to 54.95%, Fe2O3^T contents ranging from 3.99% to 14.66%, MgO contents ranging from 3.36% to 17.78%, Mg^# values ranging from 47 to 79, which are (high potassium) calc-alkaline series rocks, relatively enriched in light rare earth elements and depleted in heavy rare earth elements with δEu from 0.77 to 2.06. Furthermore, they are relatively enriched in large ion lithophile and radioactive elements such as Rb, Ba, U, K, Pb and Sr, and depleted in high field strength elements such as Nb, Ta and Ti, which is similar to the geochemical characteristics of arcmagmatic rocks in subduction zone. The magma was originated from partial melting of mantle dominated by subduction fluid metasomatism supplemented by sediment melt metasomatism. The source area is dominated by spinel bearing garnet lherzolite, and a small amount of spinel lherzolite, which experienced different degrees of crystallization differentiation in the rising process. Combined with the regional lithostratigraphic data, comprehensive analysis shows that the Early Paleozoic intermediate-basic complex in the upper reaches of Pangu River was formed in the tectonic environment of continental extensional zone (or initial rift), which is probably related to the lithosphere extension background after the collision between the Siberian plate and the Erguna massif.
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The volcanic rock characteristics and magmatic evolution of the Xingshan volcanic group in the Jingpohu area

Guo Kexin, Liu Yongshun, Nie Baofeng, Guo Lei, Zhang hui, Huang Zhicong, Hou Peng, Li Yao

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Jingpohu volcanic field is an important window for the study of intra-continental Cenozoic basalts. Previous studies on Xingshan volcanic group located in the southeast of this area have rarely been conducted and the possibility of magma assimilation and mixing in this area has been denied. The basalts of Xingshan volcanic group have been systematically studied in terms of petrology, petrochemistry and Sr-Nd-Pb isotopes. It is believed that the basalts of Xingshan volcanic group are mainl alkali basalts and trachytic basalts. The fractionation of olivine and clinopyroxene occurred during the ascent of the primary magma, and the assimilation and mixing occurred in the upper crust, with weak AFC effect. The comparison between the basalts of Xingshan volcanic group and the Jingbohu basalts shows that the alkalic basalts in both areas are derived from the partial melting of garnet peridotite, and the partial melting degree of Xingshan volcanic group is slightly lower than that of Jingbohu basalts. In terms of magmatic source region, the Xingshan volcanic group is the mixed source of PREMA and BSE end-member, while the Jingbohu basalts are the mixed source of EMII and BSE end-member at the same period. The heterogeneity of magmatic source region and the difference of magmatic evolution are the main factors causing the difference.
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Geochemistry, Ziron U-Pb dating, and Hf isotopics characteristics of ore-forming granite porphyry in Tieshanlong W ore field, southern Jiangxi Province

LI Wei, TANG Juxing, GUO Na, LIAN Dunmei, 江西省地质局第七地质大队

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Tieshanlong W ore field is located in the eastern section of Nanling W-Sn-polymetallic metallogenic belt, which have produced more than 100000 tons of wolframite around the Tieshanlong granitic complex. There have three kinds of granites: the early coarse-grained porphyritic biotite granite, the complement fine grained muscovite granite and latest granite porphyry veins, showing common geochemical characteristics of peraluminous, high-K and calc-alkali category, integrated with enrichments of SiO2, Al2O3, K2O, W, Sn, Cu, Mo, depletions of Ba、Sr、Ti、P、REE and Eu negative anomaly. Their rare earth distribution curve shows a typical “seagull” distribution with M-type tetrad effect. LA-ICP-MS zircon U-Pb dating of granite porphyry yields emplacement age of 146.7±0.5 Ma (MSDW=0.5), with 176Lu/177Hf and fLu/Hf rations of 0.000 973～0.001 989 and ﹣0.97～﹣0.94, respectively. The εHf(t) values range from ﹣17.9 to﹣10.3, and TDM2 are 1.86 Ga to 2.33 Ga, indicating primary reworking of the Paleoproterozoic crustal material. The comprehensive analysis shows that Tieshanlong ore field have three stages magmatic activities of 160～154 Ma, 154～151 Ma and 148～145 Ma, and the W-Sn mineralization is mainly occurred in the second stage. Granite porphyry is rich in Cu, Mo, W, which is closely related to the Cu-W mineralization, and show a great prospecting potential in the deep part of Tongling deposit.
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Emblem: Cultural Expression of Geological Societies

Zhang Jingfei, Wen Heng, Tatiana Fecklovia, Zhang Jiuchen

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The emblem is a professional, historical, and academic logo. As an information carrier, it expresses academic groups' academic purpose and mission with simple, vivid and easily recognizable images. At the same time, it shows academic groups' scientific and cultural connotations, such as their work objectives and academic spirit. Taking the emblem of the Geological Society of China as an analysis case, this paper discusses the role of the emblem in the scientific and cultural construction of the Society by comparing it with the cultural aims and connotations of several representative geological societies in the East and the West.
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Deformation events and the attributes of ore-controlling structures in the Yanlinsi gold field and its adjacent areas in eastern Hunan

Bai Daoyuan, Wei Fanghui, Li Bin, Zeng Guangqian, Sun Ji, Zhou Chao

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The Yanlinsi gold field is located in the south of the northeastern Hunan gold mining area, where a large number of small and medium-sized gold deposits are developed. Predecessors have not explored and analyzed the kinematic characteristics, formation ages and mechanisms of various types of deformations including ore-controlling structures in the area, affecting a comprehensive understanding of the formation and preservation laws of ore deposits. In view of this, based on the regional structural characteristics and detailed analysis of a large number of surface outcrop structures, the authors determined the deformation sequences and their ages of the Yanlinsi gold field and its adjacent areas, and then combined with deposit geology and isotope dating, discussed the mineralization ages and attributes of ore-controlling structures. The main achievements are as follows: (1) The study area has experienced 9 tectonic events from early to late such as regional NW compression in the middle Neoproterozoic, NW compression in the early Silurian, active emplacement and compression of granite bodies in the late Silurian, NW compression in the late Middle Triassic, NNW to SN compression in the Late Triassic, NWW to EW compression in the late Middle Jurassic, NW-SE extension in the Cretaceous, NE to NNE compression in the middle-late Paleogene and NW compression during the late Paleogene to early Neogene, resulted in different trends and scales of structures such as folds, thrust faults, bedding shear zones, normal faults, dextral and sinistral strike-slip faults and shear fractures, faulted basins, cleavages and kinks, as well as late deflections of some structural trends. (2) There were two stages of gold mineralization in the area during the late Silurian and late Triassic, both of which are related to contemporaneous granitic magmatic activity. (3) The main ore-bearing structures in the Yanlinsi gold field include three types: pre Mesozoic bedding brittle-ductile shear zones and interlayer faults, NW- to NWW-trending dextral strike-slip faults and shear fractures formed during Middle to Late Triassic, and internal and external contact zones of granite branches. The ore-passing structures of the late Silurian gold deposits were pre NE-trending deep thrust faults, while those of the late Triassic gold deposits were NE-trending thrust faults in the late Middle Triassic, NEE- and EW-trending thrust faults in the early Late Triassic. For the two stages of gold deposits, different types of faults formed during each deformation events after mineralization may become ore-breaking structures.
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Ore - bearing rock series of Liangshan Formation bauxite in Kaili - Huangping area, southeast Guizhou

Liu Ping, Han Zhonghua, Nie Kun

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[ ] The Dazhuyuan Formation ( C2d ) in northern Guizhou-southern Chongqing and the Liangshan Formation ( P2 l) in Kaili-Huangping area of southeastern Guizhou are both ore-bearing rock series of bauxite, both of which produce abundant spore pollen. According to the identification of pollen experts and other geological characteristics, the sedimentary age of Dazhuyuan Formation is Late Carboniferous Xiaoyao period, namely Kasimovian-Gescher period. The sedimentary age of Liangshan formation is the early Luodian period of Middle Permian, namely the early Empty Valley period. "China Mineral Geology . Guizhou Volume . Bauxite " ( 2019 ) Chapter 6 " Kaili-type Bauxite ", in the absence of geological evidence, the original Middle Permian Liangshan Formation in the Kaili-Huangping area was dismembered into two parts : the upper part of the original Liangshan Formation, carbonaceous shale, coal seams, quartz sandstone, etc. are still called the Middle Permian Liangshan Formation ( P2l ) " ; the bauxite, bauxite rock in the middle section of the original Liangshan Formation and the iron clay rock and siderite layer in the lower section were changed to the Lower Permian " Dazhuyuan Formation ( P1d ) ", and its sedimentary age was determined as " Early Permian Sakmar-Adingsk period, equivalent to the late purple period-Longlin period in China ". In this way, it will cause confusion to the stratigraphic units of the Middle Permian Liangshan Formation in Guizhou Province, which has been used for many years and has a clear definition, layered and sublayer support, which deserves serious attention.
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Growth mechanism of Neoproterozoic Ganjingzi Formation stromatolites in southern Liaoning: Comparison with modern stromatolites

YUAN Dingcheng, ZHANG Yongli, LAI Guanming, GONG Enpu, WANG Junjie, LI Depeng

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Objectives：The Ganjingzi Formation stromatolites in southern Liaoning Province are an ideal object for studying the construction of early Neoproterozoic microbial carbonate, which is of great significance for restoring paleoenvironment and paleoecology. Methods：Based on field investigation, the position of the outlying stromatolites in the Ganjingzi Formation, the macroscopic morphological characteristics of stromatolites, and the morphological changes of stromatolite columns and lamellar structures are identified and recorded. Through the observation of the laminae, the different growth stages of the laminae are distinguished, and the influence of the environment on the bifurcation and morphology of the stromatolite columns are analyzed. The stromatolites building process and characteristics of Neoproterozoic the Ganjingzi Formation stromatolites are reconstructed by comparing them with modern stromatolites. After comprehensive discussion, the growth mechanism of the Ganjingzi Formation stromatolites is summarized. Results：According to different lithology, the Ganjingzi Formation is divided into three sections from bottom to top in the Yuanjiagou area, southern Liaoning Province. Stromatolites appear at the bottom of the lower member and the top of the upper member of the Ganjingzi Formation. The stromatolites at the bottom produce stromatolite mound or the large-scale stromatolite biostrome at the top. The stromatolites colonize the hard substrate and grow perpendicular to the substrate at the beginning stage. Under the influence of hydrodynamic conditions and photosynthesis, stromatolites gradually grow vertically upward. The stromatolites in the stromatolite mound present a pattern combination of corrugate-columnar-cumulus, and the stromatolites in the stromatolite biostrome present a pattern combination of corrugate-columnar-long columnar, both of which reflect the changing trend of stromatolite morphology with increasing water depth. A comprehensive comparison of modern stromatolites shows that the microstructure of the Ganjingzi Formation stromatolites is similar to that of modern stromatolites, and growth and branch have certain comparability. Conclusions：The stromatolite laminae of the Ganjingzi Formation show different sequences of formation of light laminae and dark laminae. The morphological characteristics of stromatolites show that the growth and branched of stromatolites are affected by the environment to some extent. The formation of stromatolites is subject to environmental changes. The extensive growth of stromatolites requires ample space and a suitable environment. The presence of hard substrates creates favorable conditions for the growth of stromatolites. From micro to macro, the influence of biological factors on the growth and building characteristics of microbial mats gradually increased, while the influence of environmental factors gradually decreased.
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Spatial Distribution characteristics and Influencing Factors of Geological culture villages (or towns) in China

HU Qingqing, YANG Xiaoxia

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Geological culture villages (or towns) are important windows for science and technology to popularize geological culture, as well as carriers for developing villages and towns. The study of their spatial distribution characteristics and influencing factors is of great significance to the further evaluation and sustainable development of geological culture villages (or towns) in China. the spatial distribution characteristics of 50 geological culture villages (or towns) in China and their influencing factors are studied by using the methods of the nearest neighbor index, geographic concentration index, kernel density analysis method and geographic detector, etc. The study shows that: (1) the spatial distribution of geological culture villages (or towns) in China presents a random situation; the regional distribution shows the unbalanced trend of "more in the east and less in the west". (2) The spatial distribution density of geological culture villages (or towns) has a significant spatial difference, with the Yangtze River Delta region as the core area of high density, the northern coastal region and the eastern region of China are the sub-high density concentration areas, and there is an extended belt running through "Shanxi-Henan-Hubei-Hunan"; (3) The factors affecting the spatial distribution pattern of geological culture villages (or towns) are composed of three primary indicators: characteristic geological resources, natural conditions, and socio-economic and human resources, among which natural conditions and socio-economic and human resources have the greatest influence on the spatial distribution of geological culture villages (or towns) and have significant effects. In the process of evaluating and constructing geological culture villages (or towns) in the future, we should strengthen the survey of geological relics in each provincial regions to optimize the spatial layout of geological culture villages (or towns); speed up the evaluation of geological culture villages (or towns) in the central and western regions to drive the economic development of less developed regions; increase the investment of funds in the central and western regions and give policy inclination to promote the coordinated development of geological culture villages (or towns) in the country.
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Study on the Sedimentary Tectonic Response of the Middle-Late Permian in the Northern Edge of Bogeda mountain

LU zhishuai, XIE qingbin, ZHANG jinning, QI liqi, XU tao, CHEN jia, XIANG honghan

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The northern edge of Bogeda Mountain is the key part of Junggar Basin and Tianshan orogenic belt, thus it is also the key area to study the basin relationship. Middle-Late Permian tectonic and deposition evolution still remain controversial. In this study, we combined sedimentological and geophysical methods such as field observation, microscopic identification of rock slices, granularity analysis experiment and seismic data analysis, to study Sedimentary types and evolution, Deformation and development characteristics of basin structure, and sedimentary tectonic response of Jingzigou section and Dalongkou section which in the east and west Bogeda Mountain. The research results indicate that the Middle Permian Wulabo Formation to Hongyanchi Formation were lacustrine facies deposition, while the Upper Quanzijie Formation was alluvial fan-fluvial facies deposition, and the Upper Guodikeng and Wutonggou Formation were shore-shallow lacustrine-delta facies deposition .There are two main structural layers in the study area, the lower structural layer is extensional fault depression as the main geological structure, and the upper structural layer is foreland thrust as the main structural deformation. Multiple phases of tectonic activities control the sedimentary evolution process of Permian Bogeda area. Under the background of compressional structure, the Middle Permian lacustrine facies deposition became the Upper Permian alluvial fan-fluvial facies deposition.And the tectonic activity became stable later, and the sedimentary facies turned to shore-shallow lacustrine-delta facies.
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Characteristics and comprehensive evaluation of important geoheritages in Hainan Tropical Rainforest National Park

Lü Zhaoying, Xue Guicheng, He Yusheng, Wei Changxin, Lin Yihua, Hu Zailong, YUAN Qinmin, Lü Changyan, HUANG Wuxuan, Wang Chao, Lin Di, Chang Zhenyu, Zhang Zhizhuan

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The geoheritage resources in Hainan Tropical Rainforest National Park are extremely important components of the natural resources and natural environment in the tropical rainforest. The geological environment of the geoheritage is fundamental to the biodiversity of the tropical rainforest. The scientific protection and rational utilization of geoheritage resources is one of the important contents of the construction of Hainan Tropical Rainforest National Park. Based on the comprehensive and systematic investigation and evaluation of geoheritage resources in Hainan Tropical Rainforest National Park, according to the specification for geoheritage investigation (DZ/T 0303-2017), this paper systematically summarizes the characteristics and distribution of important geoheritage resources in Hainan Tropical Rainforest National Park, and conducts a qualitative and quantitative comprehensive evaluation and classification of their scientific and aesthetic values. The research results show that there are various types of geoheritage in Hainan Tropical Rainforest National Park, with the main categories being fundamental geology and geomorphological landscape, including 4 categories: important fossil production area, important fossil origin category, rock and soil geomorphology, water geomorphology and volcanic geomorphology, and 6 subclasses: Paleobiota Fossil Site, Carbonate Rock Landform, Intrusive Rock Landform, Detrital Rock Landform, Waterfall, and Volcanic Rock Landform, with a total of 21 important geoheritage sites. Among them, there is 1 world-level geoheritage site, 17 provincial-level geoheritage sites, and 3 sub-provincial-level geoheritage sites. Through the evaluation of geoheritage sites in Hainan Tropical Rainforest National Geopark, it provides basic information and ideas for the protection and utilization of geoheritage resources in the National Park.
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Volume 70,2024 Issue 3

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