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1.
On the Geotectonics of Southern China   总被引:10,自引:0,他引:10  
The tectonic nature of southern China has changed again and again in the Phanerozoic. In the Caledoniancycle, there existed three tectonic units——the Yangtze paraplatform, Indosinian-South China Sea paraplatformand Caledonian South China fold belt, of which the last unit is not a collisional orogenic belt but ascissor-shaped aulacogen-type geosyncline opening towards Yunnan and Vietnam. In the Indosinian cycle,South China belonged to the Tethyan tectonic domain, and no abyssal oceanic basin existed there. Since theLate Triassic, especially in the Yanshanian orogenic stage, it became a component part of the peri-Pacificcontinental-margin activation belt of eastern Asia. No Alpinc-type orogenic belt occurs in the interior of thecontinent of southern China.  相似文献   

2.
The Enshi area, Hubei Province in China, is a typical seleniferous environment, where seleniferous carbonaceous shale and carbonaceous siliceous rocks of Permian widely occur. In the 1960's, the first selenosis case in the human population in the world had even brought out at Yutangba Village, Shuanghe community, which resulted in move-off all local residenters The Enshi area possesses the advantageous natural conditions to develop Se-hyperaccnmulator. The selenosis case of human population may be related to having eaten the wild vegetable hyperaccumulating selenium. Mao Dajun (1997) found that the most seleniferous plant was cabbage in the Enshi area which contains Se 224.30 mg/kg. In order to find out Se-hyperaccnmulator in China as soon as possible, the present research made a lot of work on many numbers of wild plants which grow in Enshi, Hubei Province, China. Finally, we found Thlaspi arvenst L., the first Se-hyperaccumulator of China at Yutangba Village. In this plant, Thlaspi arvenst L., the contents of selenium (DW) are 802-870 mg/kg (the average 843 mg/kg) for the whole plant, 1121 mg/kg for root, 511 mg/kg for stem and 1427 mg/kg for leaf, respectively. The newly found Thlaspi arvenst L. by us is the most seleniferous plant which has been found in China up to now, whose Se in its leaf is higher than the international criterion of 1000 mg/kg for Se-hyperaccnmulator.  相似文献   

3.
Inductively coupled plasma mass spectrometry, inductively coupled plasma optical emission spectroscopy, hydride generation-atomic fluorescence spectrometry, emission spectrometry, X fluorescence spectrometry, and X-ray diffraction were employed to study the geochemistry and mineralogy of coal gangues from Nos. 2, 3, and 8 coal seams of the Du’erping coal mine, Xishan coalfield, Taiyuan, Shanxi Province. The study revealed that compared with the sedimentary cover, upper continent crust, Carboniferous-Permian coal from North China, as well as most coal in China, coal gangues from Nos. 2 and 3 coal seams are rich in Li, Be, Sc, Cr, Cu, Ga, Ba, Th, Nb, Cd, Pb, Ta and rare-earth elements, and coal gangues from No. 8 coal seam are rich in Li, Sc, V, Cr, Ga, U, and rare-earth elements. Compared with the Carboniferous-Permian coal from North China and most coal in China, coal gangues from Nos. 2, 3 and 8 seams are rich in Rb, V, Cs and Sr. Therefore, The Du’erping coal gangues in the Xishan coalfield are rich in most hazardous trace elements and rare-earth elements, wherein the contents of Ga and Li reach the industrial grade and have significance for industrial utilization. On the whole, coal gangues of the Shanxi Formation from the Permian are rich in more trace elements than those of the Carboniferous Taiyuan Formation. The distributions of REE show obviously dipping rightwards with negative Eu anomalies. The contents of rare-earth elements in the three seams are quite different. All of the above indicate that the source of the rare-earth elements is terrigenous debris. Minerals in No. 2 seam identified by X-ray diffraction mainly include quartz, kaolinite, in addition to calcite, pyrite, apatite, epidote, and epsomite. No. 3 seam mainly contains quartz, kaolinite, in addition to a small amount of sodium feldspar, calcium nitrate, iron ore, gypsum, and vivianite. No. 8 seam mainly contains kaolinite, dickite, quartz, illite, and a small amount of hematite and U. The correlations between major elements and trace elements in coal gangues of the Du’erping coal mine analyzed by using SPSS (Statistical Product and Service Solutions) indicate that the trace alkali elements and rare-earth elements occur mainly in such clay minerals as kaolinite.  相似文献   

4.
In 2006, the Moscow publishing house Nauka (Science) published a 246-page book by Zoya A. Bessudnova entitled Geological Research at the Natural History. Museum of Moscow University, 1759-1930 as No. 32 in its series "Sketches on the History of Geological Knowledge'. The author is a geologist and Senior Researcher in the Department for the History of Geology of the Vernadsky State Geological Museum of the Russian Academy of Sciences, and a member of the International Commission on the History of Geological Sci- ences (INHIGEO).  相似文献   

5.
Concentrations of seventeen hazardous trace elements including As, Pb, Hg, Se, Cd, Cr, Co, Mo, Mn, Ni, U, V, Th, Be, Sb, Br and Zn in the No.ll coal seam, Antaibao surface mine, Shanxi Province were determined using Instrumental Neutron Activation Analysis (INAA), Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES), Cold-Vapor Atomic Absorption Spectrometry (CV-AAS) and Graphite Furnace Atomic Absorption Spectrometry (GF-AAS). Comparisons with average concentrations of trace elements in Chinese coal show that the concentrations of Hg and Cd in the No. 11 coal seam, Antaibao surface mine are much higher. They may be harmful to the environment in the process of utilization. The variations of the trace elements contents and pyritic suffur in vertical section indicated that: (a) the concentrations of As, Pb, Mn, and pyritic sulfur decrease from roof to floor; (b) the concentrations of Cr, Zn and Mo are higher in roof, floor and lower in coal seam; (c) the concentration of Br, Sb, and Hg are higher in coal seam and lower in roof and floor; (d) the concentrations of Mo, V, Th and AI vary consistently with the ash yield. Cluster analysis of trace elements, pyritic sulfur, ash yield and major elements, such as AI, Fe, P, Ca shows that: (a) pyritic sulfur, Fe, As, Mn, Ni, Be are closely associated and reflect the influence of pyrite; (b) Mo, Se, Pb, Cr, Th, Co, Ca and A! are related to clay mineral, which is the main source of ash; (c) U, Zn, V, Na, P maybe controlled by phosphate or halite; (d) Hg, Br, Sb and Cd may be mainly organic-associated elements which fall outside the three main groups. The concentration distribution characteristics of trace elements in coal seam and the cluster analysis of major and trace elements showed that the contents of trace elements in the No. 11 coal seam, Antaibao surface mine, are mainly controlled by detrital input and migration from roof and floor.  相似文献   

6.
We propose that the level at which the conodont species Idiognathodus simulator (Ellison 1941) (sensu stricto) first appears be selected to mark the base of the Gzhelian Stage, because we believe that this is the optimal level by which this boundary can be correlated. This taxon has a short range and a wide distribution, as shown by correlation of glacial-eustatic cyclothems across the Kasimovian-Gzhelian boundary interval among Midcontinent North America and the Moscow and Donets basins of eastern Europe, based on scale of the cyclothems along with several aspects of biostrati- graphy. Outside of these areas, I. simulator (sensu stricto) is known also from other parts of the U.S., and is reported from the southern Urals and south-central China in its expected position between other widespread taxa. Its first appearance is consistent with the current ammonoid placement of the boundary (first appearance of Shumardites cuyleri), and it is also compatible with certain aspects of the distribution of Eurasian fusulinid faunas (e.g., lectotype ofRauserites rossicus).  相似文献   

7.
The Peoples' Republic of China produces and consumes the largest quantity of coal in the world; about 2.19 billion tons of coal were produced in 2005. It is estimated that coal consumption will reach 7 billion tons by 2020. Although the nationwide percentage of electrical production from coal is falling due to increased coal-fired power generation efficiency and alternative sources, China will bum more coal than any other country for the foreseeable future. China also is estimated to be the largest producer of Hg emissions (Dastoor and Larocque, 2004, Atmos. Envirn. 38:147-161). A recent comprehensive study of anthropogenic Hg emissions in China (Streets et al., 2005, Atmos. Envirn. 39:7789-7806) produced a figure of 536 tons of Hg for the year 1999 with coal combustion (all types) accounting for 38% of the total. Atmospheric Hg emission is an international problem as the upper atmosphere provides effective global transport of mercury. Although the estimates vary, China produces about three times more Hg/t of coal burnt than the USA because of the lack of modem technology for pollution control and limited use of cleaned coal. Knowledge of the mercury content, mode of occurrence, and regional distribution in Chinese coal is vital in order to assess the global atmospheric contribution from Chinese coal combustion.  相似文献   

8.
The Wangchengpo Frasnian section of Dushan County contains two atrypid brachiopod assemblages. The lower is characterized by the Atryparia (Costatrypa) dushanensis fauna that appears at the base of the Hejiazhai Member approximately in the falsiovalis to transitans conodont zones: the upper is characterized by the Radiatrypa yangi fauna, which appears in the Lujiazhai Member approximately correspondent with the hassi to Upper rhenana conodont zones. Atrypid brachiopods, together with other brachiopods from the Dushan section show that the Hejiazhai Member is of Frasnian age. Preliminary analyses of Frasnian atrypid brachiopods from sections of South China indicate that there are nine genera and subgenera including Atryparia (Costatrypa), Kyrtatrypa, Spinatrypa, lsospinatrypa, Spinatrypina, lowatrypa, Desquamatia (Desquamatia). Desquamatia (Seratrypa), and Radiatr)pa. Atrypid species diversity did not change much through the Frasnian. On a regional scale in South China, most atrypid species went extinct prior to the Frasnian/Famennian boundary. At any specific locality or section, these atrypids became extinct about 20-40 m below the Frasnian/Famennian (F/F) boundary, within the linguiformis conodont Zone, marking this as the major extinction level. Three new atrypid species are described: Atryparia (Costatrypa) dushanensis, lowatrypa pseudobodini, and Radiatrypa yangi.  相似文献   

9.
From a fresh field investigation, it has been ascertained that the Late Palaeozoic Yu'erhong (Yuernhung) flora from Yu'erhong, Yumen, Gansu, northwestern China, studied by Bohlin in 1971 includes plants from the Westphalian Yangfukou Formation and the Stephanian to Sakmarian Taiyuan Formation. The Yu'erhong flora from the Yanghukou Formation is dominated by Euramerican elements with a few elements of the Cathaysian flora. No Angarian elements have be found in this section for lack of Late Permian strata. The specimens studied by Bohlin might possibly come from the upper part of the Upper Permian at tne southeastern corner . of the Yu'erhong basin. Those fossils from different horizons and localities might be mixed with each other during collection ;so they fail to reflect the exact horizon of certain plant fossils.  相似文献   

10.
The physico-chemical conditions under which the pegmatite dyke No.3 was formed were discussed in the light of fluid-melt inclusion evidence.Our results lend support to the fractionation of hydrothermal solutions from magma,For the pegmatite dike No.3,the magmaderived hydrothermal solutions are dominated by NaCl CO2 H2O.  相似文献   

11.
<正>Recently,we carried out the National Nature Science Foundation of China(No.41273033)and Special Fund for Basic Scientific Research of Central Colleges(No.310827153407)and made some advances as follows.The main research achievements of the Paleozoic volcanic rocks in northwest China include two aspects:  相似文献   

12.
The upper Qigeblaq Formation (Fm) dolostones and the Yurtus Fm phosphatic cherts, black shales, limestones, and dolostones are widely distributed in the Precambrian/Cambrian transitional succession of the Aksu-Wushi area. Negative δ13C excursion above the Yurtus Fm/ Qigeblaq Fm boundary was determined in this study. The pronounced negative carbon isotope excursion occurs in the phosphatic chert layers at the bottom of the Cambrian Yurtus Fm, below which the first appearance of the Asteridium- Heh'osphaeridium-Comasphaeridium (AHC) acritarch assemblage zone. The δ13C curve of the lower part of the Yurtus Fm in the Aksu-Wushi area was found to be correlated with the early Cambrian δ13C curves of the Zhujiaqing Fm (Daibu Member), the lower part of the Yanjiahe Fm on the Yangtze Platform in China, the lower Tal Fm in India, the Sukharikha Fm in Siberia, and the upper part of the Tsagaan Oloom Fm in Mongolia through biostigraphy. The lower part of the Yurtus Fm in the Tarim Basin is at the Nemakit-Daldynian stage, and the Precambrian/Cambrian boundary of the Aksu-Wushi area may be located in the phosphatic chert unit which just below the first appearance AHC acritarch assemblage zone. The negative δ13C excursion (N1) across the Precambrian/Cambrian boundary in the studied section may have resulted from oceanic overturning and sea level rise.  相似文献   

13.
《《幕》》2008,31(3):353-354
Following the successful 1st IGCP 506 sym- posium in Nanjing (Nov. 2005), the 2nd Workshop in Beijing, China (during the IPC2006, June 2006) and the 3rd Workshop in Krakow of Poland (Sept. 2006), the Inter- national Geoscience Programme IGCP 506 organized its fourth international symposium from 4-8 July, 2007 in the University of Bristol, UK. The symposium focused on the topics of biodiversity of fauna, flora, palaeoenvi- ronment and stratigraphy,  相似文献   

14.
A new species, Cimbrophlebia rara sp. nov., in the family Cimbrophlebiidae(Mecoptera) is described and illustrated. This specimen was collected from the Early Cretaceous Yixian Formation at Liutiaogou in Inner Mongolia, China. This is the first record of a cimbrophlebiid from the Jehol biota. A key to all species of Cimbrophlebia is given. A preliminary review of published taxa data indicates that from the Middle Jurassic to the Early Cretaceous, Mecoptera became less diverse and less abundant in northeastern China at familiar level(from 11 to 6), generic level(from 32 to 8) and specific level(from 44 to 14).  相似文献   

15.
The Huangpu River supplies eighty percent of daily water used for life and industry for about 20 million people in Shanghai, China. Industry and domestic sewerage from the metropolis is mainly released into the Huangpu River, which flows through the Shanghai City area. The pollution caused by city life and production in the Huangpu River has occurred for years. In this paper, the contents of heavy metals (Cu, Pb, Cr, Cd, and Hg), total organic carbon (TOC), and polynuclear aromatic hydrocarbons (PAHs) in the Huangpu River are studied. Data from environmental monitoring from 1991 to 2002 are compared to understand the variation and trends of the pollution. Results indicate that metals have been reduced efficiently, but organic pollutants develop in an aggravating trend as domestic sewage increases. The variation of the organic pollutant concentrations, which are lower than those of other similar rivers of China, US, and Canada,  相似文献   

16.
An earthquake of Ms 8 struck Wenchuan County, western Sichuan, China, on May 12^th, 2008 and resulted in long surface ruptures (〉300 km). The first-hand observations about the surface ruptures produced by the earthquake in the worst-hit areas of Yingxiu, Beichuan and Qingchuan, ascertained that the causative structure of the earthquake was in the central fault zones of the Longmenshan tectonic belt. Average co-seismic vertical displacements along the individual fault of the Yingxiu-Beiehuan rupture zone reach 2.514 m and the cumulative vertical displacements across the central and frontal Longmenshan fault belt is about 5-6 m. The surface rupture strength was reduced from north of Beichuan to Qingchuan County and shows 2-3 m dextral strike-slip component. The Wenchuan thrust-faulting earthquake is a manifestation of eastward growth of the Tibetan Plateau under the action of continuous convergence of the Indian and Eurasian continents.  相似文献   

17.
Relatively abundant 17α(H)-diahopanes have been detected in the lower cretaceous lacustrine source rocks from the Lishu Fault Depression in the Songliao Basin Northeast China. Rich long chain tricyclic terpanes (carbon number up to C35) and gammacerane have been observed in those source rocks with relatively abundant 17α(H)-diahopanes, which is rarely seen in previous reports. In this paper, the formation of 17α(H)-diahopanes has been discussed from three aspects including maturity, oxidation-reduction nature of depositional environment and parent material composition by the GC/MS analyses. The results reveal that maturity and oxidation-reduction nature of depositional environment have little effect on the formation of 1 7α(H)-diahopanes in the investigated area. How- ever, the positive correlation between long-chain tricyclic terpanes and 17α(H)-diahopanes argues strongly for a common origin, and the origin is related to the algaes in saline water environment. The algaes in saline water envi- ronment may be a kind of origin of 1 7α(H)-diahopanes.  相似文献   

18.
Mercury is a pollutant of concern due to its toxic and bioaccumulative properties. Studies on the distribution and hazard of mercury in the environment are mainly focused on its forms, toxicity and the environment standard, and progresses and results have been achieved. But these studies in the past were concentrated on the scales of laboratory or smaller districts merely, such as a small unit of mineral area, vegetable base, paddy field, lake, etc. Multi-target regional geochemical survey carried out by China Geological Survey from the 1990s to now is a fundamental and commonweal geological survey, large-scale and systematical inquisition and research were conducted in 19 provinces (or municipalities directly under the Central Government) in the eastern overlay region of China, and the purpose is to provide the basic geochemical data for national economic construction, adjustment of industrial and agricultural structures and sustainable social development. Geochemical studies aim at investigating soils in these regions and 52 elements have been tested, producing a great amount of data at the same time. Methods: based on the data from 3061 samples of surface soil and 832 samples of deep soil from the project of multi-purpose geochemical survey in the Chengdu Basin, Sichuan, China, this paper describes the correlation relationship between Hg and other 48 elements and their spatial distribution in surface and deep soils of these areas by applying the method of linear regression and factor analysis.  相似文献   

19.
Heavy metals (HMs) and polycyclic aromatic hydrocarbons (PAHs) are two sorts of important pollutants, which were frequently detected in natural aquatic environments at the same time. Surfacial sediments (SSs), suspended particulates (SPs) and natural surface coatings (NSCs) are recognized as the key solid sinks and sources of heavy metals (HMs) and organic materials (OMs) in natural water systems, playing critical roles in the cycling and transformation of pollutants. The behaviors of HMs in the multi-phases (SSs, SPs and NSCs) have been well investigated, but less reports on those of PAHs, especially on those of HMs and PAHs simultaneously in the multi-phases. Hence, the relationship between HMs (Pb, Cd and Cu) and PAHs (fluorene, phenanthrene, anthracene and pyrene) in the multi-phases of Nanhu Lake in Changchun, China, was studied in this study using methods of acid digestion and extraction, in order to reveal the combined pollution of HMs and PAHs in Nanhu Lake. The information indicated that HMs and PAHs have the similar distribution patterns in the multi-phases of Nanhu Lake, with increasing levels of riMs and PAHs in the SSs, SPs and NSCs. And the enrichment capacities of SPs and NSCs for HMs and PAHs in the water were similar to each other and much greater than that of SSs, implying that SPs and NSCs contributed more to the transference and transformation of HMs and PAHs in the aquatic environments. The relationship between HMs and PAHs has been analyzed by SPSS statistical analysis, and the results showed that the significant correlation of riMs and PAHs was found in the SSs at the confidence level of p = 0.05, but Pb, Cd or Cu had no correlation with any monomer of PAHs in the SPs or NSCs, highlighting the existence of combined pollution of HMs and PAHs in SSs. This was partly due to the relative lability of SPs or NSCs compared to SSs resulting from the water quality of being varied.  相似文献   

20.
<正>Recently,we focused on the Darbut and Karamay ophiolitic mélanges in West Junggar of the Central Asian Orogenic Belt(CAOB,?engr et al.,1993;Windley et al.,2007;Xiao and Santosh,2014),and made much progress.This study was supported by the National Nature Science Foundation of China(No.41303027)and Special Fund for Basic Scientific Research of Central Colleges Project(No.2014G1271058).The achievements are illustrated as follows.  相似文献   

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