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1.
Acta Geologica Sinica (formerly the Bulletin of the Geological Society of China) beganpublication in 1922, and was published mainly in English through 1952. Since then, thejournal has been published in Chinese with English abstracts. In March 1988, Acta  相似文献   

2.
Acta Geologica Sinica(formerly the Bulletin of the Geological Society of China) began publication in 1922, and was published mainly in English through 1952. Since then, the journal has been published in Chinese with English abstracts. In March 1988, Acta Geologica Sinica appeared in English language translation. The journal is a full translation  相似文献   

3.
Acta Geologica Sinica (formerly the Bulletin of the Geological Society of China) beganpublication in 1922, and was published mainly in English through 1952. Since then, thejournal has been published in Chinese with English abstracts. In March 1988, ActaGeologica Sinica appeared in English language translation. The journal is a full translationof the Chinese edition, and follows the Chinese edition by two issues.  相似文献   

4.
To celebrate the 70th anniversary of the publication of Acta Geologica Sinica, all the papers carried in the. Acta from 1982 Vol. 56, No. 3 to 1992 Vol. 66 No. 2 were appraised by an appraisal and selection committee organized by the Geological Society of China. The outstanding papers chosen through appraisal, their titles and authors' names are hereby listed as follows:  相似文献   

5.
Extensive volcanism is one of the important features of Cenozoic geology in China.Based on temporal-spatial distribution,the volcanism was associated with three major different geological settings:1)the continental rift basalts in Northeast and North China;2)the tension-fault basalts on the continental margins of Southeast China; and 3) the collision-zone high-K volcanics in the Qinghai-Xizang Plateau and its vicinities.The characteristics of “depletion in the south and enrichment in the north“of the China continental mantle are strongly supported by isotopic evidence.The Cenozoic continental cal characters,into the following geochemical provinces:1)the depleted mantle in South China;2)the primary mantle in Northeast and NorthChina; 3)the hybrid and transi-tional mantle in the region of Shandong ,Anhui,Jiangsu and northern Zhejiang;4)the depleted mantle around the Bohai Bay and the Lower Liaohe River;5)the K-metasomatic enriched mantle in the northern part of Northeast China;and 6)the re-cycled enriched mantle in the ancient subduction zone in the Qinghai-Xizang Plateau and its surround-ings.These geochemical characteristics on a regional scale must be a reflection of the nature of lithosphere evolution.  相似文献   

6.
In the eastern part of Chian there had occurred large-scale gold mineralization during the Mesozoic,resulting in a large number of inprotant gold ore-concentrated areas.In this paper we have selected some isotope data(including four gold deposits previously studied and two gold deposis in this work)of Au-bearing quartz veins of the representative gold deposits in six impor-tant gold ore-concentrated areas in the periphery of the North China Platform and calculated their metallogenic ages using the method of Ludwig(2.90 version).The results show that the repre-sentative gold deposits in the six gold ore-concentrated areas were formed during the Mesozoic.  相似文献   

7.
In the Inner Mongolia axis and Jiaoliao anteclise along the northern margin of the North China Platform.it has been found that the strata formerly considered as Archaean and Proterozoic are in fact an ophiolite suitesimilar to the Early Palaeozoic Ondor Sum Group in the Northern Geosyncline region of China. The stratahave been named in northern Liaoning as the Qinghezhen Group. The emphasis of this paper is on the discus-sion of the simall shelly fossils found in the siliceous rocks in the upper part of the Qinghezhen Group. Thisophiolite suite stretches in an E-W direction for about 1000 km along the northern margin of the North ChinaPlatform. in which 15 fossil localities with stable stratigraphic horizons have been discovered. In this paper. 4types. 7 genera (including 5 new ones) and 10 species (including 8 new ones and 1 new subspecies) aredescribed, which are collectively referred to as the Qinghezhen Fauna. The characteristics of these fossils are:shell form simple. the maximum length not exceeding 4 mm. with obvious shell wall and wall ornaments. TheQinghezhen Fauna is comparable in shell structure of some genera and species with the Meishucun Fauna inSouth China, but differs from the latter in having only monotonous fossil groups developed in a distinctly va-ried ecological environment. The two faunas may belong to the same evolutionary stage of the Early Cambrianbut have developed parallelly in different regions. The existence of the Qinghezhen Fauna represents an impor-tant biological event in the Early Cambrian in the Northern Geosyncline region of China. The discovery of theQinghezhen Fauna will bring new knowledge and profound influence to a series of problems on basic geologyand mineral deposit prospecting such as the Cambrian faunas. biogeographical povincialism in China and thegeotectonic features of the northern margin of the North China Platform.  相似文献   

8.
Summary of the Lithospheric Dynamics in China   总被引:1,自引:0,他引:1  
This paper presents a summary of the explanatory notes for the 1: 4, 000.000 scale"Lithgspheric Dynamics Map of China and Adjacent Seas". Which gives an outline of the geological and geophysical processes that are presently active or were once active during the Cenozoic. The focus is concentrated on intraplate phenomena and on explaining them in terms of fundamental plate tectonic processes.The lithosphere in China is very heterogeneous. Its dynamics can be described in terms of the relative motions of 8 active subplates and related 17 tectonic blocks, and the characteristics of neotectonic deformation. The present-day movement and deformation of the lithosphere in China, their relationship with the deep-seated processes, and the lateral heterogeneity, mass difference and stress state within it that will tend to cause crustal movement in the future are illustrated.The intraplate tectonics and stress field are mainly controlled by the heterogeneity of the lithosphere and the mode of interaction between subplates and their boundary conditions. The collision of the Indian plate with the Eurasian plate began and proceeded along the Tethys ocean side, which has produced a strong compressional stress in western China and brought about a high shear stress in the regions round the eastern and western corners of the Himalaya block. However, the eastern part of China is directly influenced by the western Pacific plate boundaries. The minimum principal stress here is tensional. which makes the shear stress high, it may be the cause of the high seismicity in North China and maritime region of southeastern China.  相似文献   

9.
Cenozoic basalt in eastern China contains abundant ultramafic xenoliths which are specimens of pyrolitesreleased during basaltic magma eruption. A total of 405 P-T data of pyroxene in the ultramafic rocks have beencollected, which present a more precise pyroxene geotherm. The average geothermal gradient in the upper man-tle represented by the pyroxene geotherm is about 3.3℃ / km, which is much less than that derived from theconductive thermal model (≈14℃ / km), implying the great significance of convective heat transfer. The calcu-lation shows that the contributions of convective and conductive heat transfers are 79% and 21%, respectively.The perturbation in the thermal structure of the upper mantle is an important manifestation of thetectonothermal event of Cenozoic continental rifting and intense basaltic volcanism in eastern China. Based onthe pyroxene geotherm and its comparison with the current geothermal field derived from the measurements ofthe surface heat flows, it is suggested that the Moho may be a secondary thermal boundary. The currentgeothermal field and the thermal structure of the lithosphere in eastern China may mainly reflect the result ofthe tectonothermal disturbance in the Neogene-Quaternary, in other words, the lithosphere has just begun toCool.  相似文献   

10.
The formation ages of global magmatic sulfide Ni-Cu deposits are from Archean to Mesozoic,the Neoarchean and Neoproterozoic are the two peaks.In China,the formation ages of magmatic sulfide deposits are from Proterozoic to Mesozoic,and the Neoproterozoic and late Paleozoic are the two peaks,.Compared with the global magmatic deposits,there is no case study of the Archean magmatic Ni-Cu sulfide deposits in China before.The nickel deposits formed in Neoproterozoic are located on the margin of the North China Block and Yangtze Block(e.g.Jinchuan,Dapoling),and those formed in the late Paleozoic are mainly distributed in the Central Asian Orogenic Belt(CAOB).Emeishan and Tarim Large Igneous Provinces(LIPs).such as Kalatongke,Yangliuping,and Pobei.  相似文献   

11.
Nd model ages(TDM) of the Pre-Mesozoic crustal rock samples from Southeast China range from 1.2 to 3.5Ga.Two age peaks of 1.4Ga and 1.8 Ga are observed in the histogram of TDM model ages.Available U-Pb zircon inheritance ages are concentrated around 1.2-1.4Ga,1.8Ga and 2.5Ga,respectively.The combined use of Sm-Nd and U-Pb zircon inheritance ages suggests that the formation of the Precambrian curst is of episodic character.The oldest crustal nucleus may have been formed during the Late Archean(2.5Ga or older?).A rapid production of the crust took place 1.8 Ga ago,consistent with the global crust formation event at 1.7-1.9Ga.Another important episode of the addition of juvenile crustal material from the mantle in Southeast China took place 1.2-1.4Ga ago,during which the pre-existing crust was strongly reworked and/or remelted.  相似文献   

12.
Active faults have special electromagnetic effect and remote sensing characteristics, and exhibit unique im-agery marks in satellite images. A comprehensive comparison of images of active faults in eastern China and ananalysis of geologic and geomorphic data can tell us some characteristics of fault activity in the area during theneotectonic period: 1) The fault activities of the north-south tectonic zone, North China and Taiwan werestronger than those of southeastern and northeastern China; 2) the faulting in the north-south tectonic zone,North China and Taiwan has continued up to now, and most of the fault activites in southeastern andnorth-eastern China have become weaker since the Middle Pleistocene; 3) the activity is unsteady in time, mostbeing intermittent, or episodic, i.e. alternately strong and weak; 4) most active faults of a definite size can be di-vided into several segments which somewhat differ from each other in the characteristics of the activity.  相似文献   

13.
A comparison of the geochemical features of loesses of New Zealand and China indicates that the distributions of the elements and their variations reflect the fluctuations of climate which can be compared with the oxygen isotope stages and glacial periods.New Zialand loess is different in source from Chinese loess.Therefore ,some differences are also noticed in their chemical compositions .Loess accumulation in New Zealand is later than that in China.Because of more rainfall in New Zealand and different distributions of loess the elements in loess have suffered stronger leaching than in China.  相似文献   

14.
Setting up the hypostratotype of late Precambrian is the main aim of the research on the Meso- and Neoproterozoic in North China. The chronostratigraphic position is the key in this study. However, many key horizons have not been calibrated with the high-quality isotopic ages. Using the reported new U-Pb age with the Sensitive High-Resolution Ion Microprobe (SHRIMP II), a zircon U-Pb age was obtained of the ash bed in the Xiamaling Formation in North China Plate, yielding a weighted mean 206Pb/238U age of 1368±12 Ma. It is the first SHRIMP U-Pb age from the Xiamaling Formation in the North China Plate, and represents the depositing time of the middle part of the Xiamaling Formation. The zircon age plays an important role to understanding geological evolution of the North China Plate during Meso- and Neoproterozoic.  相似文献   

15.
The authors have proposed a dynamic model in this paper based on the ages,rock series and associations,Sr-Nd isotopic signatures of the Mesozoic intracontinental magmatism overlying the Cathaysian and Yangtze blocks.The model describes the relation of intracontinental collision and subduction in the Tethyan tectonic regie with Paleo-Pacific oceanic plate sudbuction-strike slip-extension in the Pacific tectonic regime.During 220-150Ma,the horizontal collision between the North China block and the Yangtze block,as well as the intracontinental subduction of some divergent microcontinental terranes in the southwestern part of South China are ascribed to the influence of the Tethyan tectonic regime,giving rise to a volume of high-Isr and low-εNd(t) S-type granites only in the Cathaysian Block.During 145-90Ma,under the geodynamic backgound of subduction-strike slip-extension of the Paleo-Pacific oceanic plate on the basis of the deep tectonic process in the Tethyan tectonic regime,high-K,alkalirich calc-alkaline and shoshonitic volcano-plutonic complexes were generated in the Yangtze block,and high-K calc-alkalic and bimodal volcano-plutonic complexes were generated in the Cathaysian block.The occurrence of A-type peralkaline granites in the coastal areas of South east China indicates the end of Mesozoic intracontinental magmatism.  相似文献   

16.
Through the study of the oxidized zone of the Debao skarn-type Cu-Sn deposit in Guangxi, the authorshave found 14 arsenate minerals, most of which are for the first time reported in China. They are mainly Cuarsenate minerals with subordinate Cu-Pb arsenate minerals and minor Fe-Pb-Ba varieties. Based on their paragenesis these minerals may be divided into the following series: (1) the clinoclasite-olivenite-cornwallite- cornubite- debaoite- copper silicarsenate association, (2) the scorodite- carminite- beudan-tite-bayldonite- duftite association, and (3) the scorodite-Ba-bearing pharmacosiderite- dussertite association. Arsenate minerals are formed generally in the oxidized zone of the sulfide-type deposits which lie in thewarm, humid and rainy torrid-subtropical zone with pH=6-8 and contain large amounts of arsenopyrite andcarbonate rocks.  相似文献   

17.
Sourthern China referred to in this paper embraces all the provinces to the south of latitude 32° N within the territory of China, exclusive of Tibet and Taiwan.The paper is based on the data obtained from temperature measurements of 680 boreholes drilled for petroleum, coal and hydrogeology. The depth of these boreholes ranges between 1,000 and 2,000m in most cases, being generally not less than 400m and reaching 7,000m in maximum.Through the elaboration and analysis of the temperature data, isotherm maps showing the temperatures at depths of 1,000m, 2,000m and 3,000m respectively and a geothermal gradient map of southern China have been compiled. These maps indicate that the earth's temperature distribution in southern China is characterized by a elatively low value in areas of its central part and those to the west of the Anning River valley of the western part(30℃, 40℃ and 70℃ at depths of 1,000m, 2,000m and 3,000m respectively), and a comparatively high value in the southeastern coastal areas and western Yunnan(60℃, 80℃ and over 120℃ respectively), and that the geothermal gradient also increases from less than 1.5℃/100 m in the central part towards both the east and the west to 2.0-3.0℃/100m or even over 4.0℃/100m.The earth's temperature distribution is strictly controlled by the deep structure of the earth's crust and is very closely related to the character of the regional geological structure, The stable central areas remarkably differ in the earth's temperature distribution from the tectonicalty active areas such as the southeastern coastal areas and the Jinggu-Tengchong area in western Yunnan, the former being lower than the latter. Meanwhile, due to the well-developed karst features in southern China, the strong groundwater flow may exert certain cooling effect on the temperature down to a depth of about 1,500m.According to the regularity of the earth's temperature distribution, regional deep structure of the earth's crust, regional geological structure and hydrogeological conditions, the following four models are proposed to explain the mechanism of formation and distribution of the earth's temperature fields in southern China: 1) onduction type; 2) convection type; 3) deep heat-source conduction-convection type; and 4) precipitation infiltration cooling type.  相似文献   

18.
Since Jurassic. intense and repeated tectonic movements have taken place in eastern China, of which theYanshanian movement is the most important. Thereby the development of the basins between the Jurassic andEogene in the studied areas may by divided into two different stages, i.e. the Yanshanian subcycle (J-K_1~1) andthe North China subcycle (K_1~2-E). The basement and tectonic stress field of the basins played an obvious role in controlling thesedimentary-tectonic development of the basins. and down-faulted basins might form under different stressstates. Besides. the shearing stress also played an important part while the basins were forming in the notedareas.  相似文献   

19.
正One of the earliest academic journals published in China.Has been indexed in SCI,CA,GeoRef,and other famous abstracts or databases.The SCI Impact Factor was between 1.25 and 2.15 during 2000-2016.Acta Geologica Sinica(English Edition)is published bimonthly in English by the Geological Society of China.As one of the oldest scientific journals in China,it was first published in 1922 with the name of the Bulletin of the Geological Society of China.It reports the latest and most important achievements in the  相似文献   

20.
To promote the rational development and use of clean coal resources in China, data on the regional and age distribution of sulfur, arsenic and other harmful elements in Chinese coal was broadly collected, tested for content, and analyzed. Coal in northwestern China is characterized by low to extremely low levels of sulfur; the coal of the Taiyuan Formation in northern China mainly has high-sulfur content; that of the Shanxi Formation is mainly characterized by low sulfur coal; and the Late Permian coal in southern China has overall higher sulfur content; other regions have low sulfur coal. The average content of harmful trace elements in the bulk of China's coal is similar to the corresponding content in the coal of the North America and the rest of the world, whereas the content of various elements (Hg, Sb and Se) is different in magnitude to the corresponding percentage in the crust. The average content of the elements Cr, Se, Co, Be, U, Br in Late Permian coal in S China ranks first in the country whereas the average content of Hg and CI in the coals of Late Carboniferous to Early Permian age in N China are the highest. The average content of Mn in Early and Middle Jurassic coal is higher in NW China. The high content of harmful elements in some coal should cause particular concern both in the development and utilization of coal.  相似文献   

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