The Yueguang gold deposit is located in Fengjia,Xinhua County,Hunan Province,South China.It represents a recently discovered small-scale gold deposit situated in the southwestern region of the Jiangnan Orogenic Belt,w...The Yueguang gold deposit is located in Fengjia,Xinhua County,Hunan Province,South China.It represents a recently discovered small-scale gold deposit situated in the southwestern region of the Jiangnan Orogenic Belt,west of the Baimashan granitic batholith.In order to discern the characteristics of the ore-formingfluids,the underlying mineralization processes,and establish a foundation for the origin of the Yueguang gold depositfluid inclusion micro-thermometry,as well as quartz hydrogen and oxygen isotope analysis,have been carried out on samples obtained from various stages of mineralization.The hydrothermal miner-alization stages within the Yueguang gold deposit can be categorized into three stages:(i)the barren,pre-ore quartz-pyrite stage(Stage Ⅰ),the quartz-pyrite-gold stage(Stage Ⅱ),and the post-ore quartz-carbonate stage(Stage Ⅲ),with the second stage being the main mineralization stage.Thefluid inclusions identified in samples from the main min-eralization stage can predominantly be described with the NaCl–H_(2)O and CO_(2)–NaCl–H_(2)O systems.These inclusions display homogenization temperatures ranging from 158.8 to 334.9℃,and thefluid salinity ranges from 0.3%to 4.0%(wt.%NaCl equiv.).Laser Raman spectroscopy analysis of individual inclusions further reveals the presence of gas-phases such as CO_(2),CH_(4),and N_(2).Isotopic analysis indicatesδ^(18)Ofluid values ranging from 3.95 to 6.7‰ and δDH_(2)O values ranging from-71.9 to-55.7‰.These results indi-cate that the ore-formingfluid of the Yueguang gold deposit belongs to metamorphic hydrothermalfluids of middle-low temperature and low salinity.In the process of ore formation,gold is transported in the form of Au(HS)2-complexes,with gold deposition being driven byfluid immiscibility.Therefore,the Yueguang gold deposit is categorized as an orogenic gold deposit dominated by metamorphic hydrother-malfluid.It may become a new target for gold exploration in the Baimashan region,central Hunan Province.展开更多
The accumulation and productivity of shale gas are mainly controlled by the characteristics of shale reservoirs;study of these characteristics forms the basis for the shale gas exploitation of the Lower Cambrian Niuti...The accumulation and productivity of shale gas are mainly controlled by the characteristics of shale reservoirs;study of these characteristics forms the basis for the shale gas exploitation of the Lower Cambrian Niutitang Formation(Fm),Southern China.In this study,core observation and lithology study were conducted along with X-ray diffraction(XRD)and electronic scanning microscopy(SEM)examinations and liquid nitrogen(N2)adsorption/desorption and CH4 isothermal adsorption experiments for several exploration wells in northwestern Hunan Province,China.The results show that one or two intervals with high-quality source rocks(TOC>2 wt%)were deposited in the deep-shelf facies.The source rocks,which were mainly composed of carbonaceous shales and siliceous shales,had high quartz contents(>40 wt%)and low clay mineral(<30 wt%,mainly illites)and carbonate mineral(<20 wt%)contents.The SEM observations and liquid nitrogen(N2)adsorption/desorption experiments showed that the shale is tight,and nanoscale pores and microscale fractures are well developed.BJH volume(VBJH)of shale ranged from 2.144×10^-3 to 20.07×10^-3 cm^3/g,with an average of 11.752×10^-3 cm3/g.Pores mainly consisted of opened and interconnected mesopores(2–50 nm in diameter)or macropores(>50 nm in diameter).The shale reservoir has strong adsorption capacity for CH4.The Langmuir volume(VL)varied from 1.63 to 7.39 cm^3/g,with an average of 3.95 cm^3/g.The characteristics of shale reservoir are controlled by several factors:(1)A deep muddy continental shelf is the most favorable environment for the development of shale reservoirs,which is controlled by the development of basic materials.(2)The storage capacity of the shale reservoir is positively related to the TOC contents and plastic minerals and negatively related to cement minerals.(3)High maturity or overmaturity leads to the growth of organic pores and microfractures,thereby improving the reservoir storage capacity.It can be deduced that the high percentage of residual gas in Niutitang Fm results from the strong reservoir storage capacity of adsorbed gas.Two layers of sweet spots with strong storage capacity of free gas,and they are characterized by the relatively high TOC contents ranging from 4 wt%to 8 wt%.展开更多
Objective The Shizishan Pb-Zn deposit is located in the southeastern margin of the Yangtze Block,and its Pb-Zn orebodies are mainly hosted in the Lower Cambrian Qingxudong Formation limestone.Previous researches have ...Objective The Shizishan Pb-Zn deposit is located in the southeastern margin of the Yangtze Block,and its Pb-Zn orebodies are mainly hosted in the Lower Cambrian Qingxudong Formation limestone.Previous researches have investigated the geological characteristics,geochemistry and fluid inclusions of this deposit.展开更多
Based on the meteorological data of representative meteorological stations in Hunan and Hubei from 1961 to 2008 years,the change character of double rice cold damage under the background of climate change were analyze...Based on the meteorological data of representative meteorological stations in Hunan and Hubei from 1961 to 2008 years,the change character of double rice cold damage under the background of climate change were analyzed adopting 30 years glide accumulation method.The analysis showed that the 30 years sliding cumulative days of mild low-temperature during spring sowing in Hunan and Hubei were decreased in the recent 50 years,as well as the 30 years sliding cumulative days of moderate low-temperature in central south Hubei,northern and western Hunan.However,there was an increase in southern Hunan,so was the 30 years sliding cumulative days of severe low-temperature.The 30 years sliding cumulative days of mild low-temperature in May reduced in Hunan and Hubei.Instead,that of moderate low-temperature in May in central south Hubei was on the rise,and it was opposite in northern and southern Hunan,but there was no obvious change in western Hunan.The 30 years sliding cumulative days of severe low-temperature showed a decreasing tendency in May in central south Hubei,northern and western Hunan,and southern Hunan showed a contrary tendency.The 30 years sliding cumulative days of mild cold dew wind in Hunan and Hubei were decreased,that of moderate cold dew wind in central south Hubei,northern and western Hunan had the same tendency,but there was a contrary tendency in southern Hunan.The 30 years sliding cumulative days of severe cold dew wind was decreased in central south Hubei and increased in western Hunan,without cold dew wind in northern and southern Hunan.展开更多
[Objective] This paper aimed at studying the agglomeration and fluctuation situation of rice production in Hunan Province during the past 10 years.[Method] Data were collected from Hunan Rural Statistical Yearbook(20...[Objective] This paper aimed at studying the agglomeration and fluctuation situation of rice production in Hunan Province during the past 10 years.[Method] Data were collected from Hunan Rural Statistical Yearbook(2001-2010).Taking the concentration index of sown area and production(CDI) and the volatility index(VI) as the main indicators,the agglomeration and fluctuation situation of paddy rice,early-season rice,middle-season rice and single-season late rice,late-season rice,good quality early-season rice,good quality middle-season rice and good quality single-season late rice,good quality late-season rice production in each major rice-producing area of Hunan Province during the past 10 years had been studied.[Result] The orders of concentration index of sown areas and production of paddy rice,early-season rice,middle-season rice and single-season late rice,late-season rice,good quality early-season rice,good quality middle-season rice and good quality single-season late rice,good quality late-season rice in Hunan Province varied,but the orders of volatility index were consistent.The stable areas,relatively stable areas and fluctuant areas in sown areas and production of different major rice-producing areas were defined.[Conclusion] The research had provided basis for optimizing the layout of rice production in Hunan Province,promoting agglomeration and development of rice production and translating the comparative advantages into the competitive advantages.展开更多
Many Propositions are made about the mechanism of emplacement of volcanoclastic material in the Bombay volcanic complex. The present paper deals exclusively with the physical features of the deposits laid by a complex...Many Propositions are made about the mechanism of emplacement of volcanoclastic material in the Bombay volcanic complex. The present paper deals exclusively with the physical features of the deposits laid by a complex tectono-magmatic process by making detailed inventory of the different kind of volcanic ejecta exposed in the Bomay Volcanic Complex (BVC), and an attempt has been made to classify the deposits genetically. A subsidenace which was hinted at earlier, may be a possible cauldron in BVC has been proposed, which might be responsible for producing such a varied and complex lithology.展开更多
This study summarized the main achievements of farmers’training and rural informatization construction in the past few years,and explored the needs of rural informatization in western Liaoning Province.The current st...This study summarized the main achievements of farmers’training and rural informatization construction in the past few years,and explored the needs of rural informatization in western Liaoning Province.The current status of agricultural development in western Liaoning and farmers’needs for education and training and rural education informatization were surveyed.The construction of an education and technical support service platform for scientific and technological farmers in western Liaoning was proposed,aiming to use information technology to train modern professional farmers.Through independent and self-learning education and training methods,it is expected to promote great improvement in the scientific and technological quality and moral level of farmers in western Liaoning and cultivate professional farmers who are educated and understand both agricultural techniques and business management.展开更多
We herein describe a partial postcranial skeleton of a sauropod dinosaur recovered from the Lower Cretaceous Jehol Group in the Beipiao area of western Liaoning Province, northeastern China. A suite of features it pos...We herein describe a partial postcranial skeleton of a sauropod dinosaur recovered from the Lower Cretaceous Jehol Group in the Beipiao area of western Liaoning Province, northeastern China. A suite of features it possesses, including the camellate internal structure of its presacral elements, the existence of pneumatocoels on the proximal ends of the dorsal ribs, and especially the medially deflected proximal portion of the femur, definitively establish the titanosauriform affinities of the specimen. It differs from other titanosauriforms in having a craniocaudally elongate coracoid with a squared cranioventral extreme and a long, smooth, and slightly convex acetabular edge of the pubis. It represents a new taxon, Dongbeititan dongi gen. et sp. nov. Comparative studies suggest that Dongbeititan is a basal titanosauriform, more derived than Euhelopus, Fusuisaurus, and Huanghetitan, but less derived than Gobititan and Jiutaisaurus. Dongbeititan represents the first sauropod dinosaur reported from the Lower Cretaceous Jehol Group of western Liaoning Province.展开更多
We report two new three-dimensionally phosphatized microfossils, Cambrolongispina reticulata gen. et sp. nov. and Cambrolongispina glabra gen. et sp. nov., from the middle Cambrian (Series 3, Drumian Stage) at Wangc...We report two new three-dimensionally phosphatized microfossils, Cambrolongispina reticulata gen. et sp. nov. and Cambrolongispina glabra gen. et sp. nov., from the middle Cambrian (Series 3, Drumian Stage) at Wangcun, Yongshun County, western Hunan, South China. They are bivalved arthropods, with thin, pliable, originally chitinous or chitin-calcareous shields (c. 350-517 I1 m long). The shields are equipped with a pair of antero-dorsal spines. The spines are internally hollow, varying in length from 1/2 of to as long as the shield length in C. reticulata, and uniformly longer than the shield length in C. glabra. The spines of C. reticulata are ornamented with a longitudinal row of conical or blade-shaped denticles along the posterior edge. Cambrolongispina lacks marginal rims, valve lobation and sulci which are diagnostic of the Bradoriida sensu stricto. It also lacks a donblure/duplicature characteristic of phosphatocopids and some bradoriids. It could be related to the Monasteriidae (which may belong to Bradoriida sensu lato), both characterized by a pair of antero-dorsal spines. Cambrolongispina may have been meiofaunai detritus feeders that lived on or within sediments. The antero-dorsal spines may have been sensory organs to detect nearby predators. The posterior denticles on these spines might have facilitated the sensory function of the spines.展开更多
China's coal dominated energy pattern has resulted in large amount of SO 2 emissions. Estimate of the sulfur related health damage cost is necessary to help perform systematic cost benefit analysis and set nat...China's coal dominated energy pattern has resulted in large amount of SO 2 emissions. Estimate of the sulfur related health damage cost is necessary to help perform systematic cost benefit analysis and set national energy and emissions control priorities. Current researches were confined to gaseous SO 2 in urban areas; however, secondary sulfate (SO 2- 4) particles can exert serious impact in a wider region. Based on the concept of “intake fraction', CALPUFF long range dispersion model and 180 sample emission sources, multiple regression equation was obtained with good correlation( r =0 85), which illustrates that populations were key parameters to determine intake fraction but source characteristics were insignificant. Based on the formula and the population distribution data, county level intake fractions were mapped for Hunan Province(range: 1 1×10 -6 -3 2×10 -6 ) of China. A combination of county level SO 2 emissions with the intake fractions yields a total 1 98 tons of sulfate(SO 2- 4) inhalation, and resulting total health damage cost to be 0 76(willingness to pay approach, WTP) or 0 16(human capital approach, HC) billion USD in 1997, about 2.1% or 0 45% of GDP in Hunan in 1997. Average health damage cost per ton of SO 2 emission is 930(WTP) or 200 USD(HC). The results demonstrated that more stringent regulation should be forced.展开更多
The characteristics and distribution patterns of detrital minerals (0. 063 -0. 125 mm) in marine sediments provide a significant indicator for the identification of the origin of sediment. The detrital mineral compo...The characteristics and distribution patterns of detrital minerals (0. 063 -0. 125 mm) in marine sediments provide a significant indicator for the identification of the origin of sediment. The detrital mineral composition of 219 surface sediment samples was ana- lysed to identify the distribution of sediments within the western Philippine Sea. The area can be divided into three mineral provinces : (Ⅰ) province east of the Philippine Trench, the detrital minerals in this province are mainly composed of calcareous or siliceous organisms, with the addition of volcanogenic minerals from an adjacent island arc; (Ⅱ) middle mineral province, clastic minerals including feldspar, quartz and colorless volcanic glass, sourced from seamounts with intermediate-acid volcanic rock, or erupting intermediate-acid volcano; (Ⅲ) province west of the Palau--Kyushu Ridge, the matter provenance within this province is complex; the small quantity of feldspar and quartz may be sourced from seamounts or erupting volcano with intermediate - acid composition, with a component of volcanic scoria sourced from a volcano erupting on the Palau--Kyushu Ridge. it is suggested that, ( 1 ) Biogenic debris of the study area is closely related to water depth, with the amount of biogenic debris controlled by carbonate lysocline. (2) Volcaniclastic matter derived from the adjacent island arc can be entrained by oceanic currents and transported towards the abyssal basin over a short distance. The weathering products of volcanic rocks of the submarine plateau (e. g. , Benham Plateau) and adjacent ridges provide an important source of detrital sedimentation, and the influence scope of them is constrained by the intensity of submarine weathering. (3) Terrigenous sediments from the continent of Asia and the adjacent Philippine island arc have little influence on the sedimentation of this study area, and the felsic mineral component is probably sourced from volcanic seamounts of intermediate-acid composition.展开更多
The central Zhuguang Mountains in Hunan Province is located at the junction of the three provinces,namely Hunan,Jiangxi,and Guangdong,where the famous Lujing uranium ore field lies.The uranium deposits occurring in th...The central Zhuguang Mountains in Hunan Province is located at the junction of the three provinces,namely Hunan,Jiangxi,and Guangdong,where the famous Lujing uranium ore field lies.The uranium deposits occurring in this area are all granite-related and they can be divided into three types,namely endogranitic ones,perigranitic ones,and contact zone types.The endogranitic uranium deposits are mainly controlled by the structural alteration zones developing within granites,with fragmentation,hematitization,and alkali metasomatism as their main mineralization characteristics.The perigranitic uranium deposits are mainly produced in the carbonaceous,siliceous,and argillaceous composite layers of epimetamorphic rocks and are controlled by fractured zones formed due to interlayer compression.The contact zone type uranium deposits mainly occur in the contact parts between the granites and favorable horizons.They have developed in favorable sections where multiple sets of structures are combined and intersected.The main metallogenic regularities of uranium in the central Zhuguang Mountains are as follows.The basic conditions for the uranium mineralization in this area include the framework consisting of regional deep large faults and their associated multi-set multi-direction favorable metallogenic structures,multi-cycle and multi-stage uranium-rich rock masses,and uranium-rich folded basement.Meanwhile,the uranium deposits in this area are closely related to granites in terms of genesis and space and they are formed in different structural parts subject to the same metallization.Furthermore,based on the summary of the characteristics and regularities of uranium mineralization in this area,the controlling factors of different types of uranium deposits in the area were explored and six metallogenic target areas were predicted.All these will provide references for the exploration of uranium deposits in this area.展开更多
Using the 1970-2005 annual precipitation and evaporation data at 80 gauge stations across Hunan province,this work analyzes the spatial distribution and variation tendency of the local droughts and floods using linear...Using the 1970-2005 annual precipitation and evaporation data at 80 gauge stations across Hunan province,this work analyzes the spatial distribution and variation tendency of the local droughts and floods using linear regression,wavelet analysis,abrupt change,clusters,Empirical Orthogonal Function (EOF) and rotated EOF (REOF).Results show that there are four dry areas and three wet areas in Hunan.The whole province exhibits a moistening trend except some small areas in western,eastern and southern Hunan.The most prominent feature of annual precipitation is that the whole province basically displays a consistent variation tendency,as far as the dominant EOF mode is concerned.In addition,the spatial features of the other EOF modes include dry-wet differences,e.g.wet (or dry) in the north versus dry (or wet) in the south,wet (or dry) in the center and dry (or wet) in the surrounding areas.The distribution of the ratios of evaporation to precipitation exhibits both common features as well as spatial differences,which can be classified into four types:South Hunan,North Hunan,Northeast Hunan,and Central Hunan.There is an abrupt change from dry to wet patterns in the early 1990s.Generally,the drought-flood distribution presents variations of three periods.In the late 2000s,Hunan province will be in a period of drought,followed by a period of flood.展开更多
We describe a new species from the family Salamandridae from northeastern Hunan Province of China based on morphological and molecular genetic evidences.The new species,Tylototriton liuyangensis,is a member of the T.a...We describe a new species from the family Salamandridae from northeastern Hunan Province of China based on morphological and molecular genetic evidences.The new species,Tylototriton liuyangensis,is a member of the T.asperrimus group,and shares a number of similarities with T.wenxianensis and T.broadoridgus.The dorsal surface of the new Tylototriton species is completely black,with nodule-like warts distributed evenly along the lateral margin of dorsal body,and there is no transverse striae between the warts.There are several diagnostic characters of the new species that differ from those of T.wenxianensis and T.broadoridgus as follows:(1)the interorbital space(IOS)is comparatively wide;(2)there is a bony ridge present on the dorsal head surface,running along the upper eyelids;(3)the space between axilla and groin(AGS)is comparatively large,with the mean male AGS approximately equal to 50%of the snout-vent length(SVL)and the mean female AGS being 53%of SVL;and(4)there is a small genital armature on the anterior angle of labial folds present inside the anal fissure of adult males during the breeding season.The result from the molecular phylogenetic analysis of the genus Tylototriton(including the type specimen of the new species)based on the complete DNA sequence of the mitochondrial ND2 gene(1035 bp)indicated that the new species was similar to T.wenxianensis,T.dabienicus,and T.broadoridgus,but formed an independent clade.This result was consistent with the morphological analysis above,supporting that the Liuyang Population represented a distinct species.展开更多
The Baoshan Cu-Pb-Zn polymetallic deposit is lied in the central Nanling mineralization zone,and belongs to the junction area of the Chenzhou-Linwu fault zone and the Leiyang-Linwu fault zone.It is a significant part ...The Baoshan Cu-Pb-Zn polymetallic deposit is lied in the central Nanling mineralization zone,and belongs to the junction area of the Chenzhou-Linwu fault zone and the Leiyang-Linwu fault zone.It is a significant part of Nanling polymetallic deposit belt.The outcropping stratas consist of upper Devonian Shetianqiao,Xikuangshan Formation,Lower Carboniferous Menggong’ao,Shidengzi,Ceshui,and Zimenqiao Formation.Igneous rocks in the Baoshan ore area mainly comprise granodiorite porphyry.Furthermore,the radio isotopic age ranges from 123 Ma to 183 Ma,belonging to the early to middle Yanshanian.展开更多
The geological corridor of Western Liaoning province is an area of length 100 km and width 20 km and located in the eastern segment of northern margin of North China Craton(NCC),with the wide distribution of Mesozoi...The geological corridor of Western Liaoning province is an area of length 100 km and width 20 km and located in the eastern segment of northern margin of North China Craton(NCC),with the wide distribution of Mesozoic granitic magmatism.It is the ideal area to study the granitic petrogenesis,the nature of magma source and the tectonic attribute.In this paper,we do the systematic researchesaboutthepetrology,geochronology,geochemistry and Zircon Hf isotopic of granitic rocks.Based on the mentioned above,we have built the geochronological framework and have discussed the petrogenesis,the nature of magma source and the tectonic setting of granitic rocks.And according to the information about the crust-mantle interaction recorded in granitic rocks and the regional data,we also discuss the relationship between Mesozoic granitic magma activities and lithosphere thinning,destruction of Craton mechanism in the eastern segment of northern margin of NCC.The Mesozoic granitic magma activities in The geological corridor of Western Liaoning province are divided into four stages(Fig.1):Late Triassic(230 Ma;28 Ma),early-middle Jurassic(194 Ma;69 Ma),Late Jurassic(161 Ma;55 Ma)and Early Cretaceous(139Ma;21 Ma).The late Triassic granitic rocks are composed of adamellite,monzogranite and diorite.The samples have high Sr,Cr,Ni content and low Yb,Y content,and the sample have high Mg#and high ratio of Sr/Y and La/Yb.The characteristics of inhomogenous negative value ofεHf(t)(-6.40;0.19)in magmatic zircons and ancient crustal TDM2 values of 1.25 Ga;.67 Ga(Fig.2),indicate that the Triassic granitic rocks were formed in a post-collisional extensional tectonic setting aftersubduction of Paleo-Asian Ocean and the subduction of Yangtze Craton,and they are the product of partial melting of ancient lower crust under the condition of the mantle-derived magma underplating,and geochemical features of the high Sr and low Y are inherited from the source of magma which is also enriched in Sr and depleted in Y.The geochemical features and assemblages of rocks formed during Jurassic-early Cretaceous are similar.The early-middle Jurassic granitic rocks are composed of syenogranite,monzogranite,quartz monzonite,granitic porphyry,granodiorite and quartz diorite.The late Jurassic granitic rocks are composed of monzogranite,granitic porphyry,and quartz diorite.The early Cretaceous granitic rocks are composed of monzogranite,quartz syenite,granitic porphyry,and quartz monzodiorite.The samples are characterized by the high SiO;content and total alkalis and are belonged to the high-K calc-alkaline series.And the characteristics of quasi-aluminous to weakly peraluminous(A/CNK<1.1,A/NK>1.0)and the negative relationship between P;O;and SiO;are similar to the characteristics of I-type granite.The samples are enriched in LREE contents and K,Pb and depleted in Nb,Ta,Ti and P.The characteristics of assemblage and geochemical features indicate the Jurassic-Cretaceous granitic rocks formed in the setting of active continental margin related to the subduction.The magmatic zircons of early-middle Jurassic granitic rocks have negativeεHf(t)(-16.60;4.15)and ancient crustal TDM2 values of 1.49 Ga;.28 Ga which indicates the primary magma is from the partial melting of ancient middle-lower crust(Fig.2).These rocks formed in the setting of active continental margin of subduction of Paleo-Pacific plate.The magma source of granitic rocks is from partial melting of the ancient lower-middle curst caused by the underplating of mantle magma,which formed in the condition of fluid derived from the dehydration of subducted slab affected on the lithosphere mantle.The magmatic zircons of late Jurassic granitic rocks have negativeεHf(t)(-26.24;18.56)and ancient crustal TDM2 values of(2.39 Ga;.87 Ga)which indicates the primary magma is from the partial melting of ancient upper-middle crust(Fig.2).And these rocks may be formed in the setting of active continental margin of intense subduction of Paleo-Pacific plate.In the intense subduction,the mantle magma is formed in the interaction of fluid derived from the dehydration of subducted slab with the lithosphere mantle,then further underplated the ancient middle-upper crust and make the ancient middle-upper curst partial melting.In this setting,the late Jurassic rocks are distributed widely in eastern North China.The samples in early Cretaceous have a wide range of values of Hf isotope:-24.92;20.88(139 Ma),-4.72;6.22(130 Ma),-17.30;11.56(125 Ma;21 Ma),and the characteristics of Hf isotope indicate the source of earlyCretaceousmagma(middle-uppercrust,middle-lower crust or juvenile crust)is very complicated(Fig.2).The early Cretaceous granitic rocks were formed in the lithosphere extensional environment when the Paleo-Pacific plate subducted/roll-backed quickly in the direction of NNW with high angle.The regional extension made the asthenosphere upwell and be unstable,and the magma of mantle was formed.Then wide mantle-crust interactions make the crust partial melt,as a result,the source of early Cretaceous igneous rocks which are distributed widely in eastern North China Craton.The participation of depleted mantle components in the process of Late Triassic rock formation in western Liaoning area indicate the time of the lithosphere thinning in the eastern segment of northern margin of NCC begin from the late Triassic(;30 Ma).The double subduction of Paleo-Asian Ocean and Yangtze Craton in the early period is the reason of the lithosphere thinning.After the double subduction,the mantle-derived magma upwell and underplate the lithosphere mantle and lower crust in a post-collisional extensional tectonic setting.As a result,the lithosphere began to thin but the Craton destruction was not obviously in this period.The participation of depleted mantle components makes the continental crust slightly reforms and grows.The eastern segment of northern margin of NCC was in the setting of active continental margin in Jurassic,and the continuing dehydration and metasomatism of subduction slab changed the physical and chemical properties of the lithosphere mantle.The initial weak subduction in early-middle Jurassic makes the lithosphere become thin but no obvious destruction of Craton.And in this period,the continental crust reformed and grew slightly.As the subduction became stronger during late Jurassic,the thickness of lithosphere in eastern segment of northern margin of NCC become thinner and the destruction of Craton occurred locally and the continental crust reformed and grew to some extent.In early Cretaceous,the change of direction and angle of subduction of Paleo-Pacific led to the regional extension,which is the reason for massive mantle material upwelling and intense crust-mantle interaction.And the lithosphere thinning and destruction of Craton reached the peak.As a result,the effects of reconstruction and hyperplasia of continental crust are obviously.In our opinions,the underplating mechanism of mantle-derived magma occurred mainly in the initial stage(early Mesozoic)oflithosphere thinning,and the delamination of lithosphere mantle or lower crust coexisted while erosion action of mantle material occurred in the stage(late Mesozoic)of strong lithosphere thinning and destruction of Craton.展开更多
Eastern Hunan-western Jiangxi, the main distribution domain of the Luoxiao MountainRange, is one of the key districts of the Circum-Pacific tectonically active belt in China, in whichNNE-trending en echelon strike-sli...Eastern Hunan-western Jiangxi, the main distribution domain of the Luoxiao MountainRange, is one of the key districts of the Circum-Pacific tectonically active belt in China, in whichNNE-trending en echelon strike-slip faulting since Cenozoic time has obviously controlled thefundamental framework of the modern land forms. Based on the study of tectonic evolution and ac-tive strike-slip faults, this paper discusses the forms, types and combinations of the modern tec-tonic land forms in this region.展开更多
By using conceptual model of BPEIR(Behavior-Pressure-Effect-Impact-Response) and Delphi method,we establish the evaluation index system of agricultural circular economy including four indices,namely index of socio-eco...By using conceptual model of BPEIR(Behavior-Pressure-Effect-Impact-Response) and Delphi method,we establish the evaluation index system of agricultural circular economy including four indices,namely index of socio-economic development,index of reducing input of resources,index of recycling of resources and index of safety of environment and resources.We conduct comprehensive evaluation on developmental level of agricultural circular economy from 1998 to 2007 in Hunan Province.The analysis results show that the agricultural circular economy of Hunan Province from 1998 to 2007,on the whole,has the tendency of development with annual growth rate of 1.89%.The annual decrease rate of recycling of resources and reducing input of resources from 1999 to 2003 is 25% and 11% respectively,which has become the main factor impeding development of agricultural circular economy.After the year 2003,it is mainly reducing input of resources.展开更多
英国传教士普鲁恩夫人于1906年撰写了来华游记The Provinces of Western China,记叙晚清时期作者及其家人在华西诸省的所见所闻,这一游记对于我们了解当时四川、重庆、云南、贵州等地的风土人情具有重要价值。目前国内外学者对The Provi...英国传教士普鲁恩夫人于1906年撰写了来华游记The Provinces of Western China,记叙晚清时期作者及其家人在华西诸省的所见所闻,这一游记对于我们了解当时四川、重庆、云南、贵州等地的风土人情具有重要价值。目前国内外学者对The Provinces of Western China所做的翻译研究不多。因此,文章拟以关联理论为指导,从词汇、句子两个层面分析来华游记The Provinces of Western China中的汉译实例,从而总结关联理论,希望对来华游记汉译具有指导意义。展开更多
基金support from several sources,including the Backbone Teacher Training Program(10912-SJGG2021-04233)the Teaching Reform Project of Chengdu University of Technology(JG2130131)+1 种基金the University-Industry Collaborative Education Project,Ministry of Education,China(22097130210756)National Natural Science Foundation of China(42272129).
文摘The Yueguang gold deposit is located in Fengjia,Xinhua County,Hunan Province,South China.It represents a recently discovered small-scale gold deposit situated in the southwestern region of the Jiangnan Orogenic Belt,west of the Baimashan granitic batholith.In order to discern the characteristics of the ore-formingfluids,the underlying mineralization processes,and establish a foundation for the origin of the Yueguang gold depositfluid inclusion micro-thermometry,as well as quartz hydrogen and oxygen isotope analysis,have been carried out on samples obtained from various stages of mineralization.The hydrothermal miner-alization stages within the Yueguang gold deposit can be categorized into three stages:(i)the barren,pre-ore quartz-pyrite stage(Stage Ⅰ),the quartz-pyrite-gold stage(Stage Ⅱ),and the post-ore quartz-carbonate stage(Stage Ⅲ),with the second stage being the main mineralization stage.Thefluid inclusions identified in samples from the main min-eralization stage can predominantly be described with the NaCl–H_(2)O and CO_(2)–NaCl–H_(2)O systems.These inclusions display homogenization temperatures ranging from 158.8 to 334.9℃,and thefluid salinity ranges from 0.3%to 4.0%(wt.%NaCl equiv.).Laser Raman spectroscopy analysis of individual inclusions further reveals the presence of gas-phases such as CO_(2),CH_(4),and N_(2).Isotopic analysis indicatesδ^(18)Ofluid values ranging from 3.95 to 6.7‰ and δDH_(2)O values ranging from-71.9 to-55.7‰.These results indi-cate that the ore-formingfluid of the Yueguang gold deposit belongs to metamorphic hydrothermalfluids of middle-low temperature and low salinity.In the process of ore formation,gold is transported in the form of Au(HS)2-complexes,with gold deposition being driven byfluid immiscibility.Therefore,the Yueguang gold deposit is categorized as an orogenic gold deposit dominated by metamorphic hydrother-malfluid.It may become a new target for gold exploration in the Baimashan region,central Hunan Province.
基金granted by the National Natural Science Foundation of China (41603046)the Natural Science Foundation of Hunan Province (2017JJ1034)
文摘The accumulation and productivity of shale gas are mainly controlled by the characteristics of shale reservoirs;study of these characteristics forms the basis for the shale gas exploitation of the Lower Cambrian Niutitang Formation(Fm),Southern China.In this study,core observation and lithology study were conducted along with X-ray diffraction(XRD)and electronic scanning microscopy(SEM)examinations and liquid nitrogen(N2)adsorption/desorption and CH4 isothermal adsorption experiments for several exploration wells in northwestern Hunan Province,China.The results show that one or two intervals with high-quality source rocks(TOC>2 wt%)were deposited in the deep-shelf facies.The source rocks,which were mainly composed of carbonaceous shales and siliceous shales,had high quartz contents(>40 wt%)and low clay mineral(<30 wt%,mainly illites)and carbonate mineral(<20 wt%)contents.The SEM observations and liquid nitrogen(N2)adsorption/desorption experiments showed that the shale is tight,and nanoscale pores and microscale fractures are well developed.BJH volume(VBJH)of shale ranged from 2.144×10^-3 to 20.07×10^-3 cm^3/g,with an average of 11.752×10^-3 cm3/g.Pores mainly consisted of opened and interconnected mesopores(2–50 nm in diameter)or macropores(>50 nm in diameter).The shale reservoir has strong adsorption capacity for CH4.The Langmuir volume(VL)varied from 1.63 to 7.39 cm^3/g,with an average of 3.95 cm^3/g.The characteristics of shale reservoir are controlled by several factors:(1)A deep muddy continental shelf is the most favorable environment for the development of shale reservoirs,which is controlled by the development of basic materials.(2)The storage capacity of the shale reservoir is positively related to the TOC contents and plastic minerals and negatively related to cement minerals.(3)High maturity or overmaturity leads to the growth of organic pores and microfractures,thereby improving the reservoir storage capacity.It can be deduced that the high percentage of residual gas in Niutitang Fm results from the strong reservoir storage capacity of adsorbed gas.Two layers of sweet spots with strong storage capacity of free gas,and they are characterized by the relatively high TOC contents ranging from 4 wt%to 8 wt%.
基金financially supported by the National Natural Science Foundation of China(grant No.41303026)
文摘Objective The Shizishan Pb-Zn deposit is located in the southeastern margin of the Yangtze Block,and its Pb-Zn orebodies are mainly hosted in the Lower Cambrian Qingxudong Formation limestone.Previous researches have investigated the geological characteristics,geochemistry and fluid inclusions of this deposit.
基金Supported by Climate Change Special Fund of China Meteorological Administration (CCSF-09-14)Major Scientific and Technological Special Project of Hunan Province (2008FJ1006)+1 种基金Scientific Research Special Fund for Public Welfare Industry (Meteorology) (GY-HY200906021)The Key Grant Project of Meteorological Bureau of Hunan Province,"The Study on Meteorological Service Integrated Platform in Modern Agriculture"
文摘Based on the meteorological data of representative meteorological stations in Hunan and Hubei from 1961 to 2008 years,the change character of double rice cold damage under the background of climate change were analyzed adopting 30 years glide accumulation method.The analysis showed that the 30 years sliding cumulative days of mild low-temperature during spring sowing in Hunan and Hubei were decreased in the recent 50 years,as well as the 30 years sliding cumulative days of moderate low-temperature in central south Hubei,northern and western Hunan.However,there was an increase in southern Hunan,so was the 30 years sliding cumulative days of severe low-temperature.The 30 years sliding cumulative days of mild low-temperature in May reduced in Hunan and Hubei.Instead,that of moderate low-temperature in May in central south Hubei was on the rise,and it was opposite in northern and southern Hunan,but there was no obvious change in western Hunan.The 30 years sliding cumulative days of severe low-temperature showed a decreasing tendency in May in central south Hubei,northern and western Hunan,and southern Hunan showed a contrary tendency.The 30 years sliding cumulative days of mild cold dew wind in Hunan and Hubei were decreased,that of moderate cold dew wind in central south Hubei,northern and western Hunan had the same tendency,but there was a contrary tendency in southern Hunan.The 30 years sliding cumulative days of severe cold dew wind was decreased in central south Hubei and increased in western Hunan,without cold dew wind in northern and southern Hunan.
基金Supported by Agricultural Specific Fund Project of Hunan Provincial Department of Finance([2011]No. 10)~~
文摘[Objective] This paper aimed at studying the agglomeration and fluctuation situation of rice production in Hunan Province during the past 10 years.[Method] Data were collected from Hunan Rural Statistical Yearbook(2001-2010).Taking the concentration index of sown area and production(CDI) and the volatility index(VI) as the main indicators,the agglomeration and fluctuation situation of paddy rice,early-season rice,middle-season rice and single-season late rice,late-season rice,good quality early-season rice,good quality middle-season rice and good quality single-season late rice,good quality late-season rice production in each major rice-producing area of Hunan Province during the past 10 years had been studied.[Result] The orders of concentration index of sown areas and production of paddy rice,early-season rice,middle-season rice and single-season late rice,late-season rice,good quality early-season rice,good quality middle-season rice and good quality single-season late rice,good quality late-season rice in Hunan Province varied,but the orders of volatility index were consistent.The stable areas,relatively stable areas and fluctuant areas in sown areas and production of different major rice-producing areas were defined.[Conclusion] The research had provided basis for optimizing the layout of rice production in Hunan Province,promoting agglomeration and development of rice production and translating the comparative advantages into the competitive advantages.
文摘Many Propositions are made about the mechanism of emplacement of volcanoclastic material in the Bombay volcanic complex. The present paper deals exclusively with the physical features of the deposits laid by a complex tectono-magmatic process by making detailed inventory of the different kind of volcanic ejecta exposed in the Bomay Volcanic Complex (BVC), and an attempt has been made to classify the deposits genetically. A subsidenace which was hinted at earlier, may be a possible cauldron in BVC has been proposed, which might be responsible for producing such a varied and complex lithology.
基金Supported by Special Project for National Educational Information Technology Research"Twelfth Five-Year"Plan 2012"Study on Construction and Application of Education Support Service Platform for Scientific and Technological Farmers in Western Liaoning"(122330890)。
文摘This study summarized the main achievements of farmers’training and rural informatization construction in the past few years,and explored the needs of rural informatization in western Liaoning Province.The current status of agricultural development in western Liaoning and farmers’needs for education and training and rural education informatization were surveyed.The construction of an education and technical support service platform for scientific and technological farmers in western Liaoning was proposed,aiming to use information technology to train modern professional farmers.Through independent and self-learning education and training methods,it is expected to promote great improvement in the scientific and technological quality and moral level of farmers in western Liaoning and cultivate professional farmers who are educated and understand both agricultural techniques and business management.
基金Funding was provided by the Bureau of Dalian Science and Technology,the Ministry of Science and Technology of China(973 Project:2006CB701405)the National Natural Science Foundation of China(40672007)the Hundred Talents Project of the Ministry of Land and Resources of China.
文摘We herein describe a partial postcranial skeleton of a sauropod dinosaur recovered from the Lower Cretaceous Jehol Group in the Beipiao area of western Liaoning Province, northeastern China. A suite of features it possesses, including the camellate internal structure of its presacral elements, the existence of pneumatocoels on the proximal ends of the dorsal ribs, and especially the medially deflected proximal portion of the femur, definitively establish the titanosauriform affinities of the specimen. It differs from other titanosauriforms in having a craniocaudally elongate coracoid with a squared cranioventral extreme and a long, smooth, and slightly convex acetabular edge of the pubis. It represents a new taxon, Dongbeititan dongi gen. et sp. nov. Comparative studies suggest that Dongbeititan is a basal titanosauriform, more derived than Euhelopus, Fusuisaurus, and Huanghetitan, but less derived than Gobititan and Jiutaisaurus. Dongbeititan represents the first sauropod dinosaur reported from the Lower Cretaceous Jehol Group of western Liaoning Province.
基金supported by the National Natural Science Foundation of China (41102003 and J1210006 to ZH41272011 to XS+3 种基金41372015 to DXP)State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing Institute of Geology and Palaeontology,Chinese Academy of Sciences (20132107 to ZH103102 to DXP)the Research Fund for Doctoral Program of High Education (20060001059 to DXP)
文摘We report two new three-dimensionally phosphatized microfossils, Cambrolongispina reticulata gen. et sp. nov. and Cambrolongispina glabra gen. et sp. nov., from the middle Cambrian (Series 3, Drumian Stage) at Wangcun, Yongshun County, western Hunan, South China. They are bivalved arthropods, with thin, pliable, originally chitinous or chitin-calcareous shields (c. 350-517 I1 m long). The shields are equipped with a pair of antero-dorsal spines. The spines are internally hollow, varying in length from 1/2 of to as long as the shield length in C. reticulata, and uniformly longer than the shield length in C. glabra. The spines of C. reticulata are ornamented with a longitudinal row of conical or blade-shaped denticles along the posterior edge. Cambrolongispina lacks marginal rims, valve lobation and sulci which are diagnostic of the Bradoriida sensu stricto. It also lacks a donblure/duplicature characteristic of phosphatocopids and some bradoriids. It could be related to the Monasteriidae (which may belong to Bradoriida sensu lato), both characterized by a pair of antero-dorsal spines. Cambrolongispina may have been meiofaunai detritus feeders that lived on or within sediments. The antero-dorsal spines may have been sensory organs to detect nearby predators. The posterior denticles on these spines might have facilitated the sensory function of the spines.
文摘China's coal dominated energy pattern has resulted in large amount of SO 2 emissions. Estimate of the sulfur related health damage cost is necessary to help perform systematic cost benefit analysis and set national energy and emissions control priorities. Current researches were confined to gaseous SO 2 in urban areas; however, secondary sulfate (SO 2- 4) particles can exert serious impact in a wider region. Based on the concept of “intake fraction', CALPUFF long range dispersion model and 180 sample emission sources, multiple regression equation was obtained with good correlation( r =0 85), which illustrates that populations were key parameters to determine intake fraction but source characteristics were insignificant. Based on the formula and the population distribution data, county level intake fractions were mapped for Hunan Province(range: 1 1×10 -6 -3 2×10 -6 ) of China. A combination of county level SO 2 emissions with the intake fractions yields a total 1 98 tons of sulfate(SO 2- 4) inhalation, and resulting total health damage cost to be 0 76(willingness to pay approach, WTP) or 0 16(human capital approach, HC) billion USD in 1997, about 2.1% or 0 45% of GDP in Hunan in 1997. Average health damage cost per ton of SO 2 emission is 930(WTP) or 200 USD(HC). The results demonstrated that more stringent regulation should be forced.
文摘The characteristics and distribution patterns of detrital minerals (0. 063 -0. 125 mm) in marine sediments provide a significant indicator for the identification of the origin of sediment. The detrital mineral composition of 219 surface sediment samples was ana- lysed to identify the distribution of sediments within the western Philippine Sea. The area can be divided into three mineral provinces : (Ⅰ) province east of the Philippine Trench, the detrital minerals in this province are mainly composed of calcareous or siliceous organisms, with the addition of volcanogenic minerals from an adjacent island arc; (Ⅱ) middle mineral province, clastic minerals including feldspar, quartz and colorless volcanic glass, sourced from seamounts with intermediate-acid volcanic rock, or erupting intermediate-acid volcano; (Ⅲ) province west of the Palau--Kyushu Ridge, the matter provenance within this province is complex; the small quantity of feldspar and quartz may be sourced from seamounts or erupting volcano with intermediate - acid composition, with a component of volcanic scoria sourced from a volcano erupting on the Palau--Kyushu Ridge. it is suggested that, ( 1 ) Biogenic debris of the study area is closely related to water depth, with the amount of biogenic debris controlled by carbonate lysocline. (2) Volcaniclastic matter derived from the adjacent island arc can be entrained by oceanic currents and transported towards the abyssal basin over a short distance. The weathering products of volcanic rocks of the submarine plateau (e. g. , Benham Plateau) and adjacent ridges provide an important source of detrital sedimentation, and the influence scope of them is constrained by the intensity of submarine weathering. (3) Terrigenous sediments from the continent of Asia and the adjacent Philippine island arc have little influence on the sedimentation of this study area, and the felsic mineral component is probably sourced from volcanic seamounts of intermediate-acid composition.
基金funded by the project titled Prospect Survey and Exploration Demonstration of Hardrock Mineral Resources such as Uranium and Thorium(12120115014101)initiated by the Tianjin Center of China Geological Survey.The data and achievements cited in this paper are mainly from relevant scientific research,geological survey,and mineral exploration projects undertaken by the No.302 Brigade of Hunan Nuclear Industry Geology Bureau in recent years.
文摘The central Zhuguang Mountains in Hunan Province is located at the junction of the three provinces,namely Hunan,Jiangxi,and Guangdong,where the famous Lujing uranium ore field lies.The uranium deposits occurring in this area are all granite-related and they can be divided into three types,namely endogranitic ones,perigranitic ones,and contact zone types.The endogranitic uranium deposits are mainly controlled by the structural alteration zones developing within granites,with fragmentation,hematitization,and alkali metasomatism as their main mineralization characteristics.The perigranitic uranium deposits are mainly produced in the carbonaceous,siliceous,and argillaceous composite layers of epimetamorphic rocks and are controlled by fractured zones formed due to interlayer compression.The contact zone type uranium deposits mainly occur in the contact parts between the granites and favorable horizons.They have developed in favorable sections where multiple sets of structures are combined and intersected.The main metallogenic regularities of uranium in the central Zhuguang Mountains are as follows.The basic conditions for the uranium mineralization in this area include the framework consisting of regional deep large faults and their associated multi-set multi-direction favorable metallogenic structures,multi-cycle and multi-stage uranium-rich rock masses,and uranium-rich folded basement.Meanwhile,the uranium deposits in this area are closely related to granites in terms of genesis and space and they are formed in different structural parts subject to the same metallization.Furthermore,based on the summary of the characteristics and regularities of uranium mineralization in this area,the controlling factors of different types of uranium deposits in the area were explored and six metallogenic target areas were predicted.All these will provide references for the exploration of uranium deposits in this area.
基金Project of Key Disciplines of Research of Hunan ProvinceNatural Science Foundation of China (40741002)
文摘Using the 1970-2005 annual precipitation and evaporation data at 80 gauge stations across Hunan province,this work analyzes the spatial distribution and variation tendency of the local droughts and floods using linear regression,wavelet analysis,abrupt change,clusters,Empirical Orthogonal Function (EOF) and rotated EOF (REOF).Results show that there are four dry areas and three wet areas in Hunan.The whole province exhibits a moistening trend except some small areas in western,eastern and southern Hunan.The most prominent feature of annual precipitation is that the whole province basically displays a consistent variation tendency,as far as the dominant EOF mode is concerned.In addition,the spatial features of the other EOF modes include dry-wet differences,e.g.wet (or dry) in the north versus dry (or wet) in the south,wet (or dry) in the center and dry (or wet) in the surrounding areas.The distribution of the ratios of evaporation to precipitation exhibits both common features as well as spatial differences,which can be classified into four types:South Hunan,North Hunan,Northeast Hunan,and Central Hunan.There is an abrupt change from dry to wet patterns in the early 1990s.Generally,the drought-flood distribution presents variations of three periods.In the late 2000s,Hunan province will be in a period of drought,followed by a period of flood.
基金supported by NSFC (31071906)the Public Welfare Scientific Research Project, Ministry of Environmental Protection of the People’s Republic of China (201209028)the Construct Program of the Key Discipline in Hunan Province (CSUFT-2013001)
文摘We describe a new species from the family Salamandridae from northeastern Hunan Province of China based on morphological and molecular genetic evidences.The new species,Tylototriton liuyangensis,is a member of the T.asperrimus group,and shares a number of similarities with T.wenxianensis and T.broadoridgus.The dorsal surface of the new Tylototriton species is completely black,with nodule-like warts distributed evenly along the lateral margin of dorsal body,and there is no transverse striae between the warts.There are several diagnostic characters of the new species that differ from those of T.wenxianensis and T.broadoridgus as follows:(1)the interorbital space(IOS)is comparatively wide;(2)there is a bony ridge present on the dorsal head surface,running along the upper eyelids;(3)the space between axilla and groin(AGS)is comparatively large,with the mean male AGS approximately equal to 50%of the snout-vent length(SVL)and the mean female AGS being 53%of SVL;and(4)there is a small genital armature on the anterior angle of labial folds present inside the anal fissure of adult males during the breeding season.The result from the molecular phylogenetic analysis of the genus Tylototriton(including the type specimen of the new species)based on the complete DNA sequence of the mitochondrial ND2 gene(1035 bp)indicated that the new species was similar to T.wenxianensis,T.dabienicus,and T.broadoridgus,but formed an independent clade.This result was consistent with the morphological analysis above,supporting that the Liuyang Population represented a distinct species.
基金Supported by the Program of Superseding Resources Prospecting in Crisis Mines in China(20089927)
文摘The Baoshan Cu-Pb-Zn polymetallic deposit is lied in the central Nanling mineralization zone,and belongs to the junction area of the Chenzhou-Linwu fault zone and the Leiyang-Linwu fault zone.It is a significant part of Nanling polymetallic deposit belt.The outcropping stratas consist of upper Devonian Shetianqiao,Xikuangshan Formation,Lower Carboniferous Menggong’ao,Shidengzi,Ceshui,and Zimenqiao Formation.Igneous rocks in the Baoshan ore area mainly comprise granodiorite porphyry.Furthermore,the radio isotopic age ranges from 123 Ma to 183 Ma,belonging to the early to middle Yanshanian.
文摘The geological corridor of Western Liaoning province is an area of length 100 km and width 20 km and located in the eastern segment of northern margin of North China Craton(NCC),with the wide distribution of Mesozoic granitic magmatism.It is the ideal area to study the granitic petrogenesis,the nature of magma source and the tectonic attribute.In this paper,we do the systematic researchesaboutthepetrology,geochronology,geochemistry and Zircon Hf isotopic of granitic rocks.Based on the mentioned above,we have built the geochronological framework and have discussed the petrogenesis,the nature of magma source and the tectonic setting of granitic rocks.And according to the information about the crust-mantle interaction recorded in granitic rocks and the regional data,we also discuss the relationship between Mesozoic granitic magma activities and lithosphere thinning,destruction of Craton mechanism in the eastern segment of northern margin of NCC.The Mesozoic granitic magma activities in The geological corridor of Western Liaoning province are divided into four stages(Fig.1):Late Triassic(230 Ma;28 Ma),early-middle Jurassic(194 Ma;69 Ma),Late Jurassic(161 Ma;55 Ma)and Early Cretaceous(139Ma;21 Ma).The late Triassic granitic rocks are composed of adamellite,monzogranite and diorite.The samples have high Sr,Cr,Ni content and low Yb,Y content,and the sample have high Mg#and high ratio of Sr/Y and La/Yb.The characteristics of inhomogenous negative value ofεHf(t)(-6.40;0.19)in magmatic zircons and ancient crustal TDM2 values of 1.25 Ga;.67 Ga(Fig.2),indicate that the Triassic granitic rocks were formed in a post-collisional extensional tectonic setting aftersubduction of Paleo-Asian Ocean and the subduction of Yangtze Craton,and they are the product of partial melting of ancient lower crust under the condition of the mantle-derived magma underplating,and geochemical features of the high Sr and low Y are inherited from the source of magma which is also enriched in Sr and depleted in Y.The geochemical features and assemblages of rocks formed during Jurassic-early Cretaceous are similar.The early-middle Jurassic granitic rocks are composed of syenogranite,monzogranite,quartz monzonite,granitic porphyry,granodiorite and quartz diorite.The late Jurassic granitic rocks are composed of monzogranite,granitic porphyry,and quartz diorite.The early Cretaceous granitic rocks are composed of monzogranite,quartz syenite,granitic porphyry,and quartz monzodiorite.The samples are characterized by the high SiO;content and total alkalis and are belonged to the high-K calc-alkaline series.And the characteristics of quasi-aluminous to weakly peraluminous(A/CNK<1.1,A/NK>1.0)and the negative relationship between P;O;and SiO;are similar to the characteristics of I-type granite.The samples are enriched in LREE contents and K,Pb and depleted in Nb,Ta,Ti and P.The characteristics of assemblage and geochemical features indicate the Jurassic-Cretaceous granitic rocks formed in the setting of active continental margin related to the subduction.The magmatic zircons of early-middle Jurassic granitic rocks have negativeεHf(t)(-16.60;4.15)and ancient crustal TDM2 values of 1.49 Ga;.28 Ga which indicates the primary magma is from the partial melting of ancient middle-lower crust(Fig.2).These rocks formed in the setting of active continental margin of subduction of Paleo-Pacific plate.The magma source of granitic rocks is from partial melting of the ancient lower-middle curst caused by the underplating of mantle magma,which formed in the condition of fluid derived from the dehydration of subducted slab affected on the lithosphere mantle.The magmatic zircons of late Jurassic granitic rocks have negativeεHf(t)(-26.24;18.56)and ancient crustal TDM2 values of(2.39 Ga;.87 Ga)which indicates the primary magma is from the partial melting of ancient upper-middle crust(Fig.2).And these rocks may be formed in the setting of active continental margin of intense subduction of Paleo-Pacific plate.In the intense subduction,the mantle magma is formed in the interaction of fluid derived from the dehydration of subducted slab with the lithosphere mantle,then further underplated the ancient middle-upper crust and make the ancient middle-upper curst partial melting.In this setting,the late Jurassic rocks are distributed widely in eastern North China.The samples in early Cretaceous have a wide range of values of Hf isotope:-24.92;20.88(139 Ma),-4.72;6.22(130 Ma),-17.30;11.56(125 Ma;21 Ma),and the characteristics of Hf isotope indicate the source of earlyCretaceousmagma(middle-uppercrust,middle-lower crust or juvenile crust)is very complicated(Fig.2).The early Cretaceous granitic rocks were formed in the lithosphere extensional environment when the Paleo-Pacific plate subducted/roll-backed quickly in the direction of NNW with high angle.The regional extension made the asthenosphere upwell and be unstable,and the magma of mantle was formed.Then wide mantle-crust interactions make the crust partial melt,as a result,the source of early Cretaceous igneous rocks which are distributed widely in eastern North China Craton.The participation of depleted mantle components in the process of Late Triassic rock formation in western Liaoning area indicate the time of the lithosphere thinning in the eastern segment of northern margin of NCC begin from the late Triassic(;30 Ma).The double subduction of Paleo-Asian Ocean and Yangtze Craton in the early period is the reason of the lithosphere thinning.After the double subduction,the mantle-derived magma upwell and underplate the lithosphere mantle and lower crust in a post-collisional extensional tectonic setting.As a result,the lithosphere began to thin but the Craton destruction was not obviously in this period.The participation of depleted mantle components makes the continental crust slightly reforms and grows.The eastern segment of northern margin of NCC was in the setting of active continental margin in Jurassic,and the continuing dehydration and metasomatism of subduction slab changed the physical and chemical properties of the lithosphere mantle.The initial weak subduction in early-middle Jurassic makes the lithosphere become thin but no obvious destruction of Craton.And in this period,the continental crust reformed and grew slightly.As the subduction became stronger during late Jurassic,the thickness of lithosphere in eastern segment of northern margin of NCC become thinner and the destruction of Craton occurred locally and the continental crust reformed and grew to some extent.In early Cretaceous,the change of direction and angle of subduction of Paleo-Pacific led to the regional extension,which is the reason for massive mantle material upwelling and intense crust-mantle interaction.And the lithosphere thinning and destruction of Craton reached the peak.As a result,the effects of reconstruction and hyperplasia of continental crust are obviously.In our opinions,the underplating mechanism of mantle-derived magma occurred mainly in the initial stage(early Mesozoic)oflithosphere thinning,and the delamination of lithosphere mantle or lower crust coexisted while erosion action of mantle material occurred in the stage(late Mesozoic)of strong lithosphere thinning and destruction of Craton.
文摘Eastern Hunan-western Jiangxi, the main distribution domain of the Luoxiao MountainRange, is one of the key districts of the Circum-Pacific tectonically active belt in China, in whichNNE-trending en echelon strike-slip faulting since Cenozoic time has obviously controlled thefundamental framework of the modern land forms. Based on the study of tectonic evolution and ac-tive strike-slip faults, this paper discusses the forms, types and combinations of the modern tec-tonic land forms in this region.
基金Supported by Social Science Planning Program of Hunan Province (09YBB050)Cultural Geography Key Discipline Construction Program of Hunan ProvinceCollege Technology Innovation Team Support Program of Hunan Province
文摘By using conceptual model of BPEIR(Behavior-Pressure-Effect-Impact-Response) and Delphi method,we establish the evaluation index system of agricultural circular economy including four indices,namely index of socio-economic development,index of reducing input of resources,index of recycling of resources and index of safety of environment and resources.We conduct comprehensive evaluation on developmental level of agricultural circular economy from 1998 to 2007 in Hunan Province.The analysis results show that the agricultural circular economy of Hunan Province from 1998 to 2007,on the whole,has the tendency of development with annual growth rate of 1.89%.The annual decrease rate of recycling of resources and reducing input of resources from 1999 to 2003 is 25% and 11% respectively,which has become the main factor impeding development of agricultural circular economy.After the year 2003,it is mainly reducing input of resources.
文摘英国传教士普鲁恩夫人于1906年撰写了来华游记The Provinces of Western China,记叙晚清时期作者及其家人在华西诸省的所见所闻,这一游记对于我们了解当时四川、重庆、云南、贵州等地的风土人情具有重要价值。目前国内外学者对The Provinces of Western China所做的翻译研究不多。因此,文章拟以关联理论为指导,从词汇、句子两个层面分析来华游记The Provinces of Western China中的汉译实例,从而总结关联理论,希望对来华游记汉译具有指导意义。