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1.
Guan Shaozeng 《《地质学报》英文版》1989,63(3):281-296
Since the coexistence of the Cretaceous and Palaeocene was ascertained in the Hengyang Basin of Hunan in the middle of the 1960's, the Cretaceous and Tertiary boundary has been discussed in several papers, but it still remains controversal. The points at issue are the connotation, stratigraphical position and lateral correlation of the Dongtang (or Chejiang) Formation. 相似文献
2.
The paper deals with the metallogenic conditions and regularities of the region ol the lower-middle reachesof the Changjiang River in China. The complicated structural network with the Changjiang (Yangtse) deepfracture as its trunk is the leading rock-and ore-controlling structure of the metallogenic belt. Thehigh-potassium granodiorites of the first magmatic sequence of the Mesozoic Yangtse syntexis type and thesodium-rich diorites of the second sequence are genetically related to the copper ore series and the iron ore se-ries respectively. and occur respectively in the block-faulted and-folded uplift area and the down-faulted vol-canic basin as well as the transitional zone between the two. The ore-hosting horizons show specific associa-tions of rocks and often contain ore beds basically of stratabound nature. 相似文献
3.
Chronostratigraphy and Stratigraphic Classification of the Cretaceous of the Songliao Basin 总被引：3，自引：0，他引：3
Wang Pujun Du Xiaodi Wang Jun Wang Dongpo Geoenergy Department Changchun University of Earth Sciences Changchun Jilin Earth Sciences Department Nanjing University Nanjing Jiangsu 《《地质学报》英文版》1996,70(2):207-218
Isotopic ages of synsedimentary clay minerals were directly determined with the ultrasonicscattering-settlement separation-K-Ar dilution technique. The apparent age of black mudstoneis 123 Ma for the Quantou Formation, 111.9-89.0 Ma for the Qingshankou Formation and77.6-76.8 Ma for the upper part of the Nenjiang Formation. The Rb-Sr isochrone age of themuddy limestone-mudstone sequence of the lower part of the Nenjiang Formation is 81 Ma andthat of the muddy evaporite of the middle part of the Quantou Formation is 122.2 Ma. On thebasis of the above isotopic ages, the authors propose a modified scheme of stratigraphic classifi-cation of the Cretaceous of the Songliao basin. 相似文献
4.
A simple mechanical model explaining the long-period (about 100-year) variations in the Earth’s rotational velocity is proposed. This model takes into account the gravitational interaction of the mantle with the solid core of the Earth and the fact that the core rotation leads that of the mantle. Well-known Earth parameters provide estimates of the gravitational torque that support the proposed model. The mathematical problem involved reduces to the classical problem of a nonlinear oscillator exposed to a constant torque. The well-known parameters of the core-mantle system result in a stable equilibrium and a stable limiting cycle on the phase cylinder of this oscillator. This equilibrium corresponds to a single angular velocity for the mantle and solid core, with no long-period oscillations in the length of the day. The limiting cycle corresponds to the core rotation leading the mantle rotation. In this case, the ellipsoidality of the gravitationally interacting bodies provides a periodic interchange of kinetic angular momentum between the mantle and solid core that results in long-period variations in the length of the day. The proposed model does not support the formerly widespread opinion that the core rotates more slowly than the mantle. 相似文献
5.
The Background Features and Formation of Chemical Elements of Groundwater in the Region of the Middle and Lower Reaches of the Yangtze River 总被引：2，自引：0，他引：2
Zeng Zhaohua Institute of Environmental Geology Jiangxi Bureau of Geology Mineral Resources Nanchang Jiangxi Shang Ruoyun 《《地质学报》英文版》1997,71(1):80-89
The paper deals with the background features, formation and distribution of the chemical el-ements K, Na, Ca, Mg, Si, Fe, Mn, Cr, Ni,V, Co, Ti, Mo, Cu, Pb, Zn, As, Hg, Cd, Be, Li, Sr, B,F, Cl, Br and I in the groundwater in the region of the middle and lower reaches of the YangtzeRiver and their relations to the composition of the water-bearing media, properties of the overly-ing rocks and soils, redox environment, and groundwater flow condition, mineralization and pHof groundwater. 相似文献
6.
Ages and Compositions of the Precambrian High-grade Basement of the Qilian Terrane and Its Adjacent Areas 总被引：14，自引：0，他引：14
WAN Yusheng XU Zhiqin YANG Jingsui ZHANG Jianxin Institute of Geology Chinese Academy of Geological Sciences Beijing 《《地质学报》英文版》2001,75(4):375-384
Based on geological, chronological, geochemical and Nd isotopic studies of the high-grade basement of the Qilian terrane, the authors have drawn the following main conclusions: (1) the high-grade basement of the Qilian terrane consists mainly of meta-argillo-arenaceous rocks and granites and its bulk part was formed in the period of 0.8-1.0 Ga (the Jinningian period); (2) most of the meta-argillo-arenaceous rocks and granitic rocks have strong negative Eu and Ba anomalies (Eu/Eu*= 0.47-0.71 and Ba/Ba*=0.16-0.64), with fDM and εNd(1.0 Ga) ranging from 1.87 to 2.26 Ga and from -8.54 to -4.06 respectively, showing relatively high maturity; and (3) the Jinningian granitic rocks are a typical product of continent-continent collision, being probably related to the formation of the supercontinent Rodinia. These studies, combined with the study of high-grade basement rocks near the Qilian terrane, suggest that before the Jinningian period, the Qilian-Qaidam northern-margin terrane and Dunhuang-Alxa terrane wer 相似文献
7.
Jiang TANG Yong LI Jiali LEI Shijie WANG Tangfu XIAO 《中国地球化学学报》2006,25(B08):122-123
This study focused on the geochemical distribution patterns and ecological effects of Cd and other heavy metals such as As, Hg, Cr, Cu, Ni, Pb, and Zn in rock, soil, water, sediment and crops in the area of the Three-Gorges Reservoir within Chongqing, and aimed at the protection of ecological environment and rational application of the local lands. This study found that the metals of Cd, Hg and Pb presented pollution in the surface environment along the Yangtze River, that is Cd〉Hg〉Pb （Cu）〉Zn〉As〉Ni〉Cr. The pollution of Cd in sediment was mainly attributable to the regional black shales, and partly to the urban sewage and garbage. The geochemical modes of metals in the sediment varied. Cr, Hg, Ni, and Pb mainly existed as residues, and Cd as carbonate. Cd exited as a high proportion in the modes of ion-exchange, carbonate, and iron-manganese oxidation, up to 63 percent. The contents of heavy metals in soiland sediment were correlated to the host clay minerals, such as illite, montmorillonite, kaolinite and chlorite. It is shown that Cd was transported with clay minerals in the Yangtze River over long distance and formed the regional anomaly. In the abnormal area of Jianping in Wushan County, higher Cd contents are reported in the local crops and local villagers＇ hairs than from the background areas. 相似文献
8.
A. P. Afanasenkov A. M. Nikishin A. V. Unger S. I. Bordunov O. V. Lugovaya A. A. Chikishev E. V. Yakovishina 《Geotectonics》2016,50(2):161-178
A new interpretation of the seismic profile series for the Taimyr Orogen and the Yenisei–Khatanga Basin is given in terms of their tectonics and geological history. The tectonics and tectonostratigraphy of the Yenisei–Khatanga and the Khatanga–Lena basins are considered. In the Late Vendian and Early Paleozoic, a passive continental margin and postrift shelf basin existed in Taimyr and the Yenisei–Khatanga Basin. From the Early Carboniferous to the Mid-Permian, the North and Central Taimyr zones were involved in orogeny. The Late Paleozoic foredeep was formed in the contemporary South Taimyr Zone. In the Middle to Late Triassic, a new orogeny took place in the large territory of Taimyr and the Noril’sk district of the Siberian Platform. A synorogenic foredeep has been recognized for the first time close to the Yenisei–Khatanga Basin. In the Jurassic and Early Cretaceous, this basin was subsided under transpressional conditions. Thereby, anticlinal swells were formed from the Callovian to the Aptian. Their growth continued in the Cenozoic. The Taimyr Orogen underwent tectonic reactivation and apparently right-lateral transpression from Carboniferous to Cenozoic. 相似文献
9.
10.
Liu Shaofeng Li Sitian Zhuang Xinguo Jiao Yangquan Lu ZongshengChina University of Geosciences Wuhan 《《地质学报》英文版》1996,70(3):233-245
Characteristics of deformation in the thrust belt and sequence stratigraphic framework in the foreland basin, structural features of the basin margin, and the episodic thrusting are studied in this paper by combining the eastern Qilian thrust belt and the Late Triassic foreland basin on the southwestern margin of Ordos. On this basis, a geological model and a mechanical model of coupling mechanism were established for the pair of thrust belt and foreland basin, and the subsidence and deposition process of the foreland basin were simulated on given parameters. 相似文献
11.
Yue Zhao 《《地质学报》英文版》1988,62(3):233-248
Through an analysis of the earliest fossils in the Precambrian-Cambrian boundary beds in various parts ofthe world, especially in the Yangtze and Siberia platforms, the author has found that the evolution of the ea-rliest skeletal animals may be divided from older to younger into three stages. The first stage (theAnabarites-Protohertzina fauna) is represented by the Anabarites-Protohertzina zone of the Meishucunian Stagein the Yangtze platform and the A. trisulcatus and P. cristata zones of the Manykayn Stage in Siberia. The sec-ond stage (the earliest orthothecimorphid and mollusc fauna) is represented by the Paragloborilus-Siphogonuchites zone of the Meishucunian Stage and the Aldanocyathus sunnaginicus zone of the TommotianStage. The third stage (the earliest hyolithimorphid and lapworthellid fauna) is represented by the Sinosachiteszone of the Meishucunian Stage and the D.regularis and D.lenaicus zones of the Tommotian Stage. The threeevolutionary stages can be used as a criterion for worldwide correlation. 相似文献
12.
ZHANG Kang WANG Darui Exploration Production Research Institute China Petroleum Chemical Corporation 《《地质学报》英文版》2004,78(3)
Almost all the oil and gas reservoirs developed in marine sedimentary strata of China have undergone processes of multi-phase reservoir formation and later modification. The irregular reservoirs are classified into three types as the Naxi, Tahe and Renqiu ones, increasing successively in the development degree of karstificated pores and fissures and the connection degree of independent reservoirs. In these reservoirs, the unity in the fluid feature, pressure and oil-gas-water interface also increases successively from the Naxi to the Renqiu type. The main body of Ordovician reservoirs of the Tahe Oilfield in the Tarim Basin is a network pool rather than a stratified, massive, stratigraphically-unconformed or weathering-crust one. The fluid nature of oil, gas and water, the interface positions and the pressures, as well as the dynamic conditions of fluids within the reservoirs during the production are all different from those in stratified or massive oil and gas reservoirs. Carbonates in the Akekule upli 相似文献
13.
Chen Baoren Liu Shuyun Earth Sciences Dept. Nanjing University Nanjing Jiangsu China Jin Peikang Geological Dept. Tulane University New Orleans LA U.S.A. Dong Shouyu Hebei Province Seismological Bureau Shijiazhuang Hebei China 《《地质学报》英文版》1993,67(4)
The fluctuation of most of the hydrograph in the deep aqueous system records the fluid pulsation in lithosphere and variation of the earth's crust. Many observations have verified that groundwater is an ideal information carrier of the crust. In this paper, the series of input (precipitation, air pressure, Earth tide etc.) and output (water level, artesian flow) of the deep aqueous system are studied by using the spectrum analysis and system theory. The application concepts of transfer function and the spectral structure of the hydrograph enrich the knowledge of the deep aqueous system. Two typical spectral structures of the hydrograph of the deep aqueous system are obtained by comparing with many water-bearing systems of the Jizhong depression. One is from well Ma-17 and the other is from the well Xinze-5. Finally, the physical models of forming the spectrum of the hydrograph are constructed on the basis of the spectrum research on the deep aqueous system. 相似文献
14.
《《地质学报》英文版》1992,66(2)
A strong tectono-magmatic thermal event has been revealed by field observations of granitic, migmatiticand metamorphic rocks in the hinterland of the Dabie Mountains. K-Ar, Ar-Ar and Rb-Sr determinationsshow that the event took place 133-117 Ma ago (Yanshanian). Contemporaneously, a southwestwardthrust-type ductile shearing at multiple levels occurred in the lower crust or at even deeper levels, suggestingthat the Dabie Mountains region was still under the influence ot strong continent-continent overlappingtectonism of the Yangtze block under the Sino-Korean block at depth. Metamorphic rocks of amphibolitefacies, migmatites and deep structural deformations resulting from this tectonothermal event are now exposedto the surface. The present features of the Dabie Mountains thus have appeared only since ca. 100 Ma B.P. Theblock composed of the Dabie Group is not an uplift or shield which would have undergone a long-continuederosion. 相似文献
15.
ZHANG Kang WANG Darui Exploration Production Research Institute China Petroleum Chemical Corporation 《《地质学报》英文版》2004,78(3)
Almost all the oil and gas reservoirs developed in marine sedimentary strata of China have undergone processes of multi-phase reservoir formation and later modification. The irregular reservoirs are classified into three types as the Naxi, Tahe and Renqiu ones, increasing successively in the development degree of karstificated pores and fissures and the connection degree of independent reservoirs. In these reservoirs, the unity in the fluid feature, pressure and oil-gas-water interface also increases successively from the Naxi to the Renqiu type. The main body of Ordovician reservoirs of the Tahe Oilfield in the Tarim Basin is a network pool rather than a stratified, massive, stratigraphically-unconformed or weathering-crust one. The fluid nature of oil, gas and water, the interface positions and the pressures, as well as the dynamic conditions of fluids within the reservoirs during the production are all different from those in stratified or massive oil and gas reservoirs. Carbonates in the Akekule upli 相似文献
16.
Dong WANG Shaoming PAN Jichun WU Qingping ZHU Chang LIU 《中国地球化学学报》2006,25(B08):168-169
In the history, the Yellow River nurtured Chinese civilization. It is respected as the ＂ancestor of the four large rivers in China＂ and praised as ＂the mother river of China＂. At the same time, the Yellow River is regarded as ＂the misery of China＂ and considered as the most complex river hard to control in the world. Today, the Yellow River is also one large river greatly influenced by human activities in the world. The safety of the Yellow River, particularly flood control, is always the most important issue for governing and developing the country. Great achievements have been made after many years of efforts for controlling the Yellow River. However, since the nineties of 20 century, some new problems occurred, such as sharp reduction of flux to sea, dry rivercourse, worsen environment, etc. Rapidly shrinking riverbed and two-level perched stream are disadvantageous to flood safety especially. The new concepts and new practices are urgently needed to control the river. Therefore, the Yellow River Conservancy Committee of Ministry of Water Resources had continuously carded out flow and sediment diversion each year from 2002 to 2005. To timely probe into the new issues produced after flow and sediment diversion, and in order to deepen the understanding of rules for the Yellow River＇s water and sediment and provide reference and experience to the researchers for other large rivers, five hydrologic and hydraulic characteristics of the Yellow River, such as lack of water, much of sediment, different resources of water and sediment, inconsistency between water and sediment and frequency of sink switching and route changing, are described. Flow and sediment diversion of the Yellow River is also reviewed. Under flow and sediment diversion, 相似文献
17.
Doklady Earth Sciences - The influence of variations in fo-, fa-, en-, fs-, di-, an-, and ab-components in a high-Mg basaltic melt on the topology of the spinellide liquidus was analyzed using the... 相似文献
18.
Analysis of the degree of contamination and evolution in the last 100 years of the composition of the bed sediments of the Anllóns Basin 总被引：3，自引：2，他引：1
Rosa Devesa-Rey M. T. Barral J.-M. Jouanneau F. Díaz-Fierros 《Environmental Earth Sciences》2010,61(7):1401-1417
In this study, five cores of the Anllóns River bed sediments were analyzed in order to evaluate the downcore and downstream
variations in their chemical composition. The first step was the evaluation of the metal distribution in the bulk (<2 mm)
and fine fractions (<63 μm). The analysis revealed that most of the metals followed the same trend in both fractions, although
the fine fraction presented usually higher concentrations. However, the concentration of both fractions tended to equalize
with increasing contamination. No general increase was observed in the metal concentrations toward the surface which could
be attributed to recent anthropogenic contributions. Instead, the distributions were homogeneous or peaked at various depths
downcore. The most important historical feature was observed at the mouth of the river, at 96-cm depth, corresponding to the
end of the eighteenth century. Upcore increased metal concentrations in parallel with increased fine fraction occurred from
this depth, which were attributed to a bridge construction and consequent changes in sediment dynamics. As the metal concentrations
can be influenced by variations in texture or other sediment characteristics, the second step was to evaluate the efficiency
of several normalized indexes in the assessment of the degree of contamination, by calculating the enrichment factor (EF),
the geoaccumulation index (I
GEO) and the pollution load index (PLI). The EFs obtained were <10, thus revealing little anthropogenic inputs to the basin.
The I
GEO produced higher values when compared with the EFs. Instead of absolute EF or I
GEO absolute values, the use of cumulative probability plots allowed identifying more accurately potential outliers indicating
contamination. Only one population was identified for Zn and Pb, with a reduced number of outliers at the highest concentrations
for Pb. As shown, a more complex plot with the outliers identified at C4 and C5. Finally, the PLI allowed determining the
absence of a significant contamination in the bed sediments. The bioavailable and non-geogenic fractions contribute up to
a 90% of the total concentrations in the case of As and Cu, and showed similar (dissimilar) profiles in comparison with total
metals. Also, the quality guidelines were surpassed, so the high solubility of As, Zn, Pb and Ni in the sediments revealed
the need to monitor the bed sediment quality of the Anllóns River. 相似文献
19.
李统锦 《中国地球化学学报》1989,8(1):84-96
Experiments indicate that the solubility of cassiterite can be enhanced by increasing either acidity or alkalinity in hydrothermal solutions as a consequence of the duality of tin.The minimum solubility of cassiterite is found in neutral solutions.F-and CL-coordination compounds of Sn can alternate with hydroxyl coordination compounds with changing pH in the solutions.In this case,F^- and Cl^- and OH^- can be substituted with each other.The dissolution reaction of cassiterite is of reducing nature.High temperature and acidic reducing environment are favorable for the dissolution of cassiterite and the trans-port of Sn^2 compounds in fluids or solutions.High-temperature fluoride and chloride fluids can all dissolve,extract and enrich Sn to form F^- and /or Cl-coordination compounds,However,Fplays a more important role than Cl.F-coordination compounds are more stable and efficient than Cl-coordination compounds during the transport an enrichment of Sn in melts or solutions.The solubili-ty of cassiterite and the amount of Sn extracted from granitic melt depend not only on T,P,pH and Eh in the fluids or solutions,but also on the amounts of dissociated F^- and Cl^- in the fluids. 相似文献