Medical Diagnosis Based on Multi-Attribute Group Decision-Making Using Extension Fuzzy Sets,Aggregation Operators and Basic Uncertainty Information Granule

Accurate medical diagnosis,which involves identifying diseases based on patient symptoms,is often hindered by uncertainties in data interpretation and retrieval.Advanced fuzzy set theories have emerged as effective tools to address these challenges.In this paper,new mathematical approaches for handling uncertainty in medical diagnosis are introduced using q-rung orthopair fuzzy sets(q-ROFS)and interval-valued q-rung orthopair fuzzy sets(IVq-ROFS).Three aggregation operators are proposed in our methodologies:the q-ROF weighted averaging(q-ROFWA),the q-ROF weighted geometric(q-ROFWG),and the q-ROF weighted neutrality averaging(qROFWNA),which enhance decision-making under uncertainty.These operators are paired with ranking methods such as the similarity measure,score function,and inverse score function to improve the accuracy of disease identification.Additionally,the impact of varying q-rung values is explored through a sensitivity analysis,extending the analysis beyond the typical maximum value of 3.The Basic Uncertain Information(BUI)method is employed to simulate expert opinions,and aggregation operators are used to combine these opinions in a group decisionmaking context.Our results provide a comprehensive comparison of methodologies,highlighting their strengths and limitations in diagnosing diseases based on uncertain patient data.

High mobility group box 1 in the central nervous system:regeneration hidden beneath inflammation

High-mobility group box 1 was first discovered in the calf thymus as a DNA-binding nuclear protein and has been widely studied in diverse fields,including neurology and neuroscience.High-mobility group box 1 in the extracellular space functions as a pro-inflammatory damage-associated molecular pattern,which has been proven to play an important role in a wide variety of central nervous system disorders such as ischemic stroke,Alzheimer’s disease,frontotemporal dementia,Parkinson’s disease,multiple sclerosis,epilepsy,and traumatic brain injury.Several drugs that inhibit high-mobility group box 1 as a damage-associated molecular pattern,such as glycyrrhizin,ethyl pyruvate,and neutralizing anti-high-mobility group box 1 antibodies,are commonly used to target high-mobility group box 1 activity in central nervous system disorders.Although it is commonly known for its detrimental inflammatory effect,high-mobility group box 1 has also been shown to have beneficial pro-regenerative roles in central nervous system disorders.In this narrative review,we provide a brief summary of the history of high-mobility group box 1 research and its characterization as a damage-associated molecular pattern,its downstream receptors,and intracellular signaling pathways,how high-mobility group box 1 exerts the repair-favoring roles in general and in the central nervous system,and clues on how to differentiate the pro-regenerative from the pro-inflammatory role.Research targeting high-mobility group box 1 in the central nervous system may benefit from differentiating between the two functions rather than overall suppression of high-mobility group box 1.

金融机构ESG投资的“漂绿”与“反漂绿”——基于DWSGroup的案例分析

深化绿色金融发展、助力经济绿色发展,是实现“双碳”目标的重要途径,特别是在ESG理念盛行的今天,金融机构的ESG投资行为因其深远影响而颇受投资者青睐,但层出不穷的“漂绿”现象也牢牢制约着绿色金融的发展,制约着ESG投资的发展。西方国家作为绿色金融发展先驱,从信息披露、制度监管、实践探索等方面对“漂绿”现象进行了研究和治理。本文在学习其先进经验的基础上,基于舞弊三角理论对DWSGroup案例进行分析,从压力、机会和自我合理化因素角度对金融机构ESG投资“漂绿”行为的动因进行分析,并据此提出我国“反漂绿”体系框架,以期为绿色金融的平稳发展和“双碳”目标的实现作出贡献。

Permo-Carboniferous Radiolarians from the Wupata'erkan Group,Western South Tianshan, Xinjiang, China

The Wupata'erkan Group, also called Wupata'erkan Formation, distributed in the South Tianshan, Xinjiang, China, mainly consists of gray and dark gray fine-grained clastic rocks, interlayered with volcanic rocks, carbonates and cherts. Some ultra-basic rocks (blocks) punctuate the formation. The formation was variously assigned to Silurian-Middle Devonian, Silurian-Lower Devonian, and pre-Devonian, mainly based on Atrypa bodini Mansuy, Hypothyridina parallelepipedia (Brour.) and Prismatophyllum hexagonum Yoh collected from the limestone interlayers, respectively. However, radiolarian fossils obtained from 24 chert specimens of the Wupata'erkan Group, mainly include Albaillella sp. cf. A. undulata Deflandre, Albaillella sp. cf. A. paradoxa Deflandre, Albaillella cf. A. deflandrei Gourmelon, Albaillella sp. cf. A. indensis Won, Albaillella sp. cf. A. excelsa Ishiga, Kito and Imoto, Albaillella sp. and Latentifistulidae gen. et. sp. indet., are earliest Carboniferous and Late Permian. The earliest Carboniferous assemblage is characterized by Albaillella sp. cf. A. undulata Deflandre, Albaillella sp. cf. A. paradoxa Deflandre, Albaillella cf. A. deflandrei Gourmelon and Albaillella sp. cf. A. indensis Won, and the Late Permian assemblage by Albaillella sp. cf. A. excelsa Ishiga, Kito and Imoto. This new stratigraphic evidence indicates that the Wupata'erkan Group is possibly composed of rocks with different ages from Silurian to Permian, and therefore, it is probably an ophiolite melange. The discovery of Late Permian Albaillella sp. cf. A. excelsa provides more reliable evidence supporting the existence of a Permian relic ancient oceanic basin in the western part of Xinjiang South Tianshan.

Origin and controlling factors of chlorite coatings—an example from the reservoir of T_3x Group of the Baojie area,Sichuan Basin,China

The study of the chlorite coatings always attracts scholars in China and other countries because the chlorite coatings play an important role in the preservation of residual primary pores in sandstone reservoirs.At present,the study of the origin and the controlling factors is relatively few.The occurrence,time of formation,genesis,controlling factors,and the mechanism of chlorite coatings inhibiting quartz overgrowths were studied in detail with thin section and SEM analysis.Samples were from the sandstone reservoirs of the T3x Group in the Baojie area,the transitional zone from the middle to the south of Sichuan Basin.The results indicate that the chlorite coatings on the walls of the pore spaces are oriented perpendicular to grain surfaces in the form of isopachous(even-thickness) grain-coating,while the chlorite coatings at the contacts between adjacent detrital grains are arranged with a preferred orientation tangential to the surface of detrital grains.The chlorite coatings were formed in the eogenetic stage.They were formed by recrystallization of Fe-rich clay films during the syndepositional period,and chlorite cements would be recrystallized after the coatings’ formation.The formation of chlorite coatings was mainly controlled by the depositional environment,provenance conditions,and diagenetic environment.The presence of chlorite coatings could result in the preservation of primary pores in deeply buried sandstone reservoirs by effectively inhibiting quartz overgrowths and the development of compaction and pressure solution.

Geochemistry of the Batang Group in the Zhaokalong Area, Yushu, Qinghai： Implications for the Late Triassic Tectonism in the Northern Sanjiang Region, China

The Batang Group in the Zhaokalong area not only hosts an important Fe-Cu polymetallic deposit but also reveal important insights for the Late Triassic tectonism in the northern Sanjiang region. In order to delineate the tectonic setting and evolutionary process of the paleo arc-basin system, geochemical studies on the Batang Group strata have been carried out. The results suggest that andesite in the Zhaokalong area mainly belongs to the tholeiite series and is characterized by obvious fractionation of LREE and HREE, enrichment in LILE and depletion in HFSE, and a distinctly elevated δ^（34）SCDT average of 10.5‰. The sandstone is classified as lithic sandstone, which is also characterized by obvious fractionation of LREE and HREE, as well as weak negative Ce and Eu anomalies. The limestone displays positive Eu anomalies, with δ^（13）CPDB ranging from-1.3‰ to 4.4‰ and δ^（18） OSMOW ranging from 14.6‰ to 22.5‰. These results indicate that the andesite has a dual signature of both arc andesite and rift volcanic rocks, whereas the sandstone may be formed in an active continental margin, and the limestone could be deposited in a weak oxidizing shallow sea. The sandstone in the Zhaokalong area represents sedimentation in a platform slope facies, corresponding to the main stage of the Jinshajing oceanic basin subduction during the middle period of Late Triassic. The continental arc volcanic activity resulted from subsequent strengthened subduction, forming the andesite in the North Qiangtang backarc basin. Afterwards, the limestone was formed after the cessation of magmatic activity. The information gleaned from the Batang Group strata helped constrain the evolution of the paleo-Jomda island arc and Jinshajiang oceanic subduction in the Late Triassic.

Home range variation of two different-sized groups of golden snub-nosed monkeys(Rhinopithecus roxellana) in Shennongjia, China: implications for feeding competition

Knowledge on the home range size of a species or population is important for understanding its behavioral and social ecology and improving the effectiveness of conservation strategies. We studied the home range size of two different-sized groups of golden snub-nosed monkeys(Rhinopithecus roxellana) in Shennongjia, China. The larger group(236 individuals)had a home range of 22.5 km2 from September2007 to July 2008, whereas the smaller group(62 individuals) occupied a home range of 12.4 km2 from November 2008 to July 2009. Both groups exhibited considerable seasonal variation in their home range size, which was likely due to seasonal changes in food availability and distribution. The home range in any given season(winter, spring, summer, or winter+spring+summer) of the larger group was larger than that of the smaller group. As the two groups were studied in the same area, with the confounding effects of food availability thus minimized, the positive relationship between home range size and group size suggested that scramble feeding competition increased within the larger group.

Geochemistry and Sm-Nd systematics of the 1.67 Ga Buanji Group of southwestern Tanzania: Paleo-weathering, provenance and paleo-tectonic setting implications

We present major and trace and Nd-isotopic data of the^1.67 Ga Buanji Group of southwestern Tanzania in order to constrain the nature of their protolith and the intensity of chemical weathering in the source terranes and make inferences on the nature of climatic conditions during the late Paleoproterozoic in the region. Major and trace element contents of the shales from three stratigraphic formations are comparable to those of the post-Archaean Australian Shale(PAAS) and the average Proterozoic Shale(PS). They are characterized by enrichments in LREE relative to HREE((La/Yb)_(CN)=9.07-13.2;(Gd/Yb)cN = 1.51-1.85) and negative Eu anomalies(Eu/Eu~* = 0.61-0.81); features which are comparable to those of PAAS and PS, indicating upper continental sources. Provenance proxy ratios,together with abundances of Cr, Ni, Co and V that increase up-stratigraphy suggest a decreasing input of felsic detritus up-stratigraphy. Chemical Indices of Alteration(CIA) for the lower, middle and upper Buanji formations are 81. 76 and 79, respectively. These indices largely indicate intermediate(ca. 60-80)to extreme(>80) weathering intensities of the precursor rocks. These observations may suggest the prevalence of warm, humid climates during the late Paleoproterozoic in the region.The lower Buanji Formation yielded a depleted mantle Nd model age(T_(DM)) of 、2100 Ma which indicates an Eburnean parentage. T_(DM) ages of 2486-2155 Ma and 2535-2379 Ma obtained from middle and upper Buanji formations, respectively, suggest a progressive increase of sedimentary input from the Tanzania Craton up-stratigraphy. The Eburnean T_(DM) ages of the lower Buanji rocks are attributed to their derivation through denudation of a decaying topographic high composed predominantly of rocks that were generated during the Palaeoproterozoic Ubendian orogenesis, possibly in the realm of Columbian Supercontinent assembly. Overlapping T_(DM) ages between the middle and upper Buanji formations suggest multiple sources involving mixing of detritus from Archaean cratonic rocks and the Palaeoproterozoic Ubendian belt. However, the Archaean signal is relatively more pronounced in the upper Buanji Formation, suggesting sediments derivation from the craton, to the north of the basin. The middle Buanji Formation suggests more diverse protolith,given the relatively larger spread in the T_(DM) ages. The Nb/Ta, Zr/Sm and Ce/Pb ratios coupled with the negative Nb and Ta anomalies, relative to primitive mantle, suggest that the tectonic setting of the source rocks for the Buanji sediments was a subduction zone akin to that generating modern sland Arc Basalts. Thus, we suggest that the Buanji's palaeogeography is consistent with an extensional continental backarc basin during the late Paleoproterozoic.

Redefinition and Formation Age of the Tanjianshan Group in Xitieshan Region, Qinghai

The Tanjianshan Group,which was previously divided into a,b,c and d formations,has been controversial for a long time.It mainly distributes in the northern margin of Qaidam Basin and is an important early Paleozoic greenschist facies metamorphic volcanic sedimentary rock formation.Detailed field investigation and zircon LA-ICPMS U-Pb dating of the key strata suggest that the original lower part of a Formation （a-1） versus the original middle upper of d Formation （d-3 and d-4）,the original upper part of a Formation （a-2） and b Formation versus the original lower part of d Formation （d-1 and d-2） of Tanjianshan Group are contemporaneous heterotopic facies volcanicclasolite deposit,respectively.The former formations formed during the middle-late Ordovician （463-458 Ma）,while the latter ones formed in the late Ordovician （about 445 Ma）.The original c formation of Tanjianshan Group,which formed after 430 Ma,is similar to the Maoniushan Formation of Kunlun Mountains and north Qaidam Basin.According to the rules of stratigraphic division and naming,new stratum formations of Tanjianshan Group are re-built and divided into Duancenggou （O1-2td）,Zhongjiangou （O2-3tz） and Xitieshan （O3tx） formations.The original c Formation is separated from Tanjianshan Group and is renamed as the Wuminggou Formation （S3-D1W）,which shows a discordant contact with underlying Tanjianshan Group and overlying Amunike Formation （D3a）.The zircon U-Pb age frequency spectrogram of Tanjianshan Group indicates three prominent peaks of 430 Ma,460 Ma and 908 Ma,which is consistent with the metamorphic and magmatic crystallization ages obtained from para-and orthogneisses in north Qaidam HP-UHP metamorphic belt,implying that strong Caledonian and Jinningian tectonic and magmatic events have ever happened in North Qaidam.

Ecological species groups and interspecific association of vegetation in natural recovery process at Xiejiadian landslide after 2008 Wenchuan earthquake

Wenchuan earthquake on 12 May 2008 triggered numerous landslides, which disturbed vast areas of vegetation in northwest Sichuan. However, based on our primary field investigation at Xiejiadian landslide in July 2009, we found an obvious increase of the number of plant species and then we made a hypothesis that, after earthquake, vegetation at this landslide might recover by itself. In this paper, we conduct a newly field investigation at Xiejiadian landslide during November 2014 to verify this hypothesis. We investigated plant species composition at total 56 sites(trees 4, shrubs 16 and herbs 36, respectively), and calculated the Schluter's variance ratio, important values, x2 test, associationcoefficient, Ochiai index, Pearson's and Spearman's correlation coefficients, and Ecological species groups. Species sharply increased to 84 species belonging to 66 genera and 54 families, forming a complete life form containing trees, shrubs, herbs, and ground layers while only herbs detected in 2009. Moreover, an overall positive and moderately related interspecies association was detected for most of species pairs. Of total 84 species, twenty five were identified as dominant species and could be divided into four positive ecological species groups. This study verified our proposed hypothesis of self-recovery of vegetation in landslide triggered by the earthquake, and found Alnus cremastogyne, Rhus chinensis, Litsea cubeba, Vitis piasezkii and Anemone vitifolia would play a constructive role during the continuing succession of vegetation at Xiejiadian landslide.

Variations in leaf functional traits among plant species grouped by growth and leaf types in Zhenjiang,China

Leaf functional traits are adaptations that enable plants to live under various environmental conditions. This study aims to determine the differences in leaf functional traits among plants grouped by growth habit, leaf life span,leaf lifestyle, leaf form, and origin. Specific leaf area（SLA） of perennial or evergreen species was lower than that of annual or deciduous species because longer-lived leaves of perennial or evergreen species require more investment in structural integrity and/or defense against disturbances, especially with any resource constraint. SLA of large individuals was lower than that of small individuals. The low SLA in large individuals can improve their response to changing light and water conditions because increasing plant height is advantageous for light competition, but it can also impose a cost in terms of structural support and water transport. Petioles of plants with compound leaves were significantly longer than those of simple leaves because branching is expensive in terms of gaining height. SLA of plants increased with increasing invasiveness accordingly, and SLA of invasive plants was higher than that of their native congeners because invasive plants should invest more biomass on leaf growth rather than leaf structures per unit area to achieve a higher growth rate.Overall, variation in leaf functional traits among different groups may play an adaptive role in the successful survival of plants under diverse environments because leaf functional traits can lead to pronounced effects on leaf function,especially the acquisition and use of light. Plant species with different growth and leaf traits balance resource acquisition and leaf construction to minimize trade-offs and achieve fitness advantages in their natural habitat.

Conditional Similarity Reductions of Jimbo—Miwa Equation via the Classical Lie Group Approach

Recently, the Clarkson and Kruskal direct method has been modified to find new similarity reductions (conditional similarity reductions) of nonlinear systems and the results obtained by the modified direct method cannot be obtained by the current classical and/or non-classical Lie group approach. In this paper, we show that the conditional similarity reductions of the Jimbo-Miwa equation can be reobtained by adding an additional constraint equation to the original model to form a conditional equation system first and then solving the model system by means of the classical Lie group approach.

Paleotectonic Setting of Dongyan Group of Middle and Upper Proterozoic in Central Fujian Province

The central Fujian Province, situated on the juncture of paleo-uplift of Wuyishan, Yongmei Late Paleozoic depression and the eastern volcanic rift-faulting zone, is mainly composed of the outcropped metamorphic basements in the Middle-Late and Early Proterozoic, which constitute two upper and lower giant thick formations of Precambrian volcanic-sedimentary cycles, respectively. The formation of Dongyan Group is an important Middle-Upper Proterozoic component, and the Dongyan Group is directly related to massive sulfide deposit in this area. In recent years, plenty of lead, zinc, copper, silver and gold deposits have been found and explored. The Precambrian paleorift setting of the central Fujian Province served as a favorite metallogenic background for the formation of large- and superlarge-scale volcanic massive sulfide (VMS) lead and zinc polymetal deposits. The Dongyan Group consists chiefly of a set of ancient volcanic sedimentary formations that are composed mainly of greenschist. Its major lithologic types comprise greenschist, marble, quartzite and granofels class including various components. The metamorphic rocks of Dongyan Group are the main composition of Middle and Upper Proterozoic volcanic-sedimentary cycle. The original rock of Dongyan Group, a stable rock association, is volcanic sedimentation and normal marine sedimentation. But the original volcanic rocks, basic and acid, are bimodal. The volcanic rocks were formed in the extensional continental rift setting.

The First Discovery of Rhyolite Interlayer in the Mugagangri Group in the Bangonghu-Nujiang Suture Zone, Tibet and the U-Pb Dating

Objective The Mugagangri group （MP）, named by Wen Shixuan （1979） in the southeast Mugegebori Mountain which is the main peak of Mugagangri, is a flysch formation with deep semi-deep marine sedimentary features in the Bangonghu -Nujiang suture zone （BNSZ）. The lithology is mainly composed of sandstones, graywackes, siltstones and silty mudstones with low-grade metamorphism. The previously defined Mugagangri group continues from east to west for nearly 2000 km in BNSZ as a matrix part associated with ophiolitic melange blocks, and is considered to be part of the deep marine sedimentary cover of ophiolites.

Collaboration Optimization of Flight Schedule in Beijing⁃Tianjin⁃Hebei Airport Group

The coordinated and integrated development of regional airport group system has been identified as an important research topic in the field of air traffic management in China.However,due to the clear limitation on airspace resources and severe traffic congestion,it is necessary to further study the problem of flight schedule coordination optimization for airport clusters.We take the Beijing-Tianjin-Hebei airport Group as an example and construct an optimization model of flight schedule with the minimum adjustment and delay.The design of the implementation algorithm is proposed.As demonstrated by the simulation results,the flight delay in the Beijing-Tianjin-Hebei multi-airport system is noticeably reduced by applying both the optimization model and the algorithm proposed in this paper.

Surface Wave Group Velocity Tomography Imaging from Ambient Noise for Fujian Province and Its Adjacent Areas

Two-month continuous waveforms of 108 broadband seismic stations in Fujian Province and its adjacent areas are used to compute noise cross-correlation function(NCF). The signal quality of NCF is improved via the application of time-frequency phase weighted stacking. The Rayleigh and Love waves group velocities between 1 s-20 s are measured on the symmetrical component of the NCF with the multiple filter method. More than 5,000 Rayleigh wave dispersion curves and about 4,000 Love wave dispersion curves are obtained and used to invert for group velocity maps. This data set provides about 50 km resolution that is demonstrated with checkerboard tests. Considering the off great circle effect in inhomogeneous medium, the ray path is traced based on the travel time field computed with a finite difference method. The inverted group velocity maps show good correlation with the geological features in the upper and middle crust. The Fuzhou basin and Zhangzhou basin showed low velocity on the short period group velocity maps. On the long period group velocity maps, the low velocity anomaly in the high heat flow region near Zhangzhou and clear velocity contrast across the Zhenghe-Dapu faults, which suggests that the Zhenghe-Dapu fault might be a deep fault.

Sedimentary Facies, Provenance and Geochronology of the Heshangzhen Group: Implications for the Tectonic Evolution of the Eastern Jiangnan Orogen, South China

The Neoproterozoic Jiangnan orogen plays an important role in the study of the Precambrian tectonic evolution of South China. The tectonic nature of the Neoproterozoic sedimentary basins is still controversial, due to poor understanding of the sedimentary sequences and the lack of geochronological data. Here, we present sedimentological, provenance and geochronological data from the Heshangzhen Group in the eastern Jiangnan orogen. Sedimentological analysis shows that the Luojiamen Formation was deposited in a submarine fan, and the overlying Hongchicun Formation was deposited in front of a fan delta. The youngest detrital zircons constrain the lower Luojiamen and Hongchicun formations with ages of 827.3 ± 8.4 Ma and 825 ± 12 Ma, respectively. The sandstones of the Luojiamen Formation are characterized by a large number of intermediate to felsic volcanic grains, suggesting a volcanic arc source. In contrast, quartz and sedimentary lithic grains increase in the Hongchicun Formation, showing a new input from a collisional orogenic source. Detrital zircon from six sandstone samples in the Luojiamen and Hongchicun formations yield similar age spectra of 930–820 Ma with a peak at ca. 845–860 Ma, with one main cluster at 930–820 Ma. Detrital zircons of 930–845 Ma show a positive value of εHf(t)(+2.4 to +11, mean +7.6), which is similar to the volcanic arc of the nearby Shuangxiwu Group. There are a minor group of zircons with U-Pb ages ranging from 820 Ma to 845 Ma from the middle part of the Luojiamen Formation and Hongchicun Formation, with εHf(t) values between-20 to +2.4, which are consistent with the characteristics of the Shuangqiaoshan Group. within light of the bidirectional paleocurrents in the Luojiamen Formation, it is speculated that the zircons of 820–845 Ma were recycled from the Shuangqiaoshan Group, which is derived from a continental arc to the northwest. Our data suggests that the Luojiamen Formation was formed in an inter-arc basin, while the Hongchicun Formation was formed in an accretionary wedge-top basin. When juxtaposed with the conglomeratic characteristics at the bottom of the Luojiamen Formation, it is believed that the unconformity represented by the ‘Shen Gong Movement' reflects the rapid erosion and accumulation process of island arc volcanic material. The disconformity between the Luojiamen and Hongchicun formations is the imprint of transition from inter-arc basin to accretionary wedge-top basin,which represents the collision between the Shuangxiwu arc and the Yangtze Plate.

Oxygen pressure leaching-flotation joint process for Jinbaoshan platinum group minerals

An oxygen pressure leaching-flotation joint process was proposed to treat Jinbaoshan platinum group minerals to produce a desired concentrate. The result demonstrates that leaching parameters which include particle size, stirring speed, liquid-solid ratio, and the dosage of calcium lignosulfonate, simultaneously affect the leaching rates of base metals and the recovery of platinum group metals (PGMs). The complete dissolution of base metals sulfides leads to a reduction in the amount of flotation carrier for enriching PGMs, decreasing the recovery of PGMs. The optimum leaching conditions are determined as follows: liquid-solid ratio of 10 mL/g, 73% occupancy of ore particle size below 0.043 mm, stirring speed of 400 r/min, and 0.6 g dosage of calcium lignosulfonate. Under optimal conditions, the leaching rates of Cu, Ni and Fe are 87.6%, 87.6% and 90.3%, respectively. The grade of PGMs enriched in the flotation concentrate is 420 g/t through the flotation technology.

Stromatolite characteristics of Mesoproterozoic Shennongjia Group in the northern margin of Yangtze Block, China

Mesoproterozoic Shennongjia Group in Shennongjia Area can be divided into three subgroups in ascender order. Of which the lower subgroup includes Yingwodong, Dayanping, Macaoyuan, Luanshigou, Dawokeng and Kuangshishan formations;the middle subgroup is formed by Yemahe, Wenshuihe and Shicaohe formations;the upper subgroup consists of Songziyuan and Wagangxi formations. Stromatolites developed very well in the carbonate rocks of each subgroup in Shennongjia Group. Based on descriptions of stromatolites macrotypes and their characteristics, this paper studied the formation environments, discussed the relationship among types, sizes, abundance of stromatolites and sedimentary environment, and established the formation and development pattern of stromatolites. As a result, this research also reveals the paleoenvironment and paleoclimate during the period of the Shennongjia Group deposited, which is beneficial to the study of paleoenvironment, paleogeography and paleoclimate, stratigraphic succession and regional correlation of the northern edge of Yangtze block. Stromatolites of Shennongjia Group are mainly conical, columnar, domal, wavy, stratiform and stromatolite reefs. The columnar and conical stromatolites are well developed. Conical stromatolites are mainly monomers, with a variety of pyramidal types, ranging in diameter from a few millimeters to several meters and formed in the high energy subtidal zone and tidal lagoon environment. Most of the columnar stromatolites are medium to small sizes implied a wide and gentle slope environment at that time. Stratiform (including wavy) stromatolites are larger scales and extends far away and distributed most widely in almost every horizon in the carbonate rocks. Stratiform stromatolites can be formed in low energy environments such as subtidal and intertidal zones and supratidal belts. Wavy stromatolites often developed in the hydrodynamic energy condition from weak energy intertidal zone gradually strengthened to the below of the high energy supratidal. Although stromatolite reefs can be a single or multiform combination, they developed mainly consisted of laminar or small walled columnar and large domal stromatolites. Shicaohe Formation also partially developed large domical stromatolites, the depositional environment is from the upper intertidal to supratidal zone. Stromatolite in Shennongjia Group usually appears as a combination of “Stratiform (wavy)-dome-columnar-coniform ” or “stratiform-dome-coniform-columnar-dome-stratiform ” vertieally, which represents the seawater depth from shallower to deeper or from shallow to deep and then to shallow again. These phenomenons generally reflected a stable sea level and companied with a high frequency oscillation. Comprehensive researches on the stratigraphy, sedimentary facies, sedimentary environment and the stromatolite types and their characteristics in the Shennongjia Group indicated that the Shennongjia Area is located on a gentle slope of carbonate platform in the passive continental edge, generally, i.e., one of warm and humid climate shallow water zone or/and a cold-drought climate, and had been experienced with eustatic cycles during the Shennongjia Group deposited.

Sedimentary Environments of the Cangfanggou Groupin Junggar Basin,Xinjiang,in Response to Climate and Tectonic Regime

Detailed studies of petrology, palaeocurrent direction, paiaeogeomorphology and palaeohydrody-namics have been conducted for the Permian-Triassic Cangfanggou Group in the foredeep of the Bogda Mountains in the southeastern Junggar Basin, Xinjiang. Sedimentary environments and fades of alluvial fans and pebbly braided rivers, sandy braided rivers, meandering rivers, low-sinuosity rivers, swamps and fresh-water lakes are recognized in the group. Climate and tectonics of source areas strongly controlled the evolution of the sedimentary environments and facies in the foredeep. The block faulting in the Bogda Mountains increased the ground slope, which led to a drastic increase in the grain size of the sediments. Humid climate, being beneficial to plant growth, would provide protection of channel banks and at the same time weaken chemical weathering in the source area, thus large amounts of clay materials are available for the formation of clay plugs. As a result, stable banks and meandering river belts are formed. Conversely, increasing aridity would strengthen mechanical weathering and reduce the number of clay plugs. Besides, plants would diminish gradually and channels would become more mobile. In this case the decrease of transported clay materials would reduce the stability of the bank and result in a wider and shallower channel. Therefore, humid climate is beneficial to the formation of meandering rivers even if there is strong block faulting in the source areas and the ground slope is very large. As aridity further increases, plants would diminish and vanish at last, the meandering rivers prevalent under humid climate conditions would be transformed to low-sinuosity rivers even if the ground is gentle and the land is tectonically stable. And as the climate became more arid and the source area uplifted intensively to provide more sedimentary materials, low-sinuosity rivers would be transformed to braided ones quickly, and wedge-like sedimentary bodies of the braided rivers would then advance towards the lower reaches. The increasingly arid climate led to prevailing mechanical and diminishing plant protection to the banks. Both active tectonic regime and humid climate resulted in very shallow and mobile channels, i.e. a braided river system.The climate plays an important role in the evolution of rivers and lakes. The sinuosity and braiding parameters of channels are a result of complex interaction between climate (clay material supply, plant protection of the banks, flood events and so on) and tectonic regime (lithology of the source area, slopes and so on). Both factors can be estimated by sedimentological studies in the foothill belt.