Table of Content

20 March 1999, Volume 5 Issue 1

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Article

REM ARKS 0N EARTH SYSTEM SCIENCE

Yuan Daoxian

1999, 5(1):  1-6. 

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Defined as “that branch of knowledge or study dealing with Earth as a whole; study of the sum of processes operating in the atmosphere, hydrosphere, biosphere and lithosphere and the interactions between these compartments”, Earth System Science is considered as principal melody of geosciences at the 21st century. The naive academic thinkings of Earth System Science could be traced hack to 100 years ago, when Thomas C. Chamberlin (1898) put forward a hypothesis that alternate functioning of internal agencies (crustal movement, volcanism which emit (into atmosphere) and external agencies (weathering, photosynthesis, formation of organic matters, and the deposition of fossil fuels and carbonate rocks which withdraw CO2 from the atmosphere) has brought about warm and cold periods in the Earth’s history. He considered this mechanism responsible for the advancement and retreat of Permian and Quaternary glaciations. The term of Earth System Science first appeared as the name of a special NASA committee in 1983, and then a guideline book for global change study and monitoring Earth’s processes in 1988. The implementation of the ideas and methodologies of Earth System Science has played an important role in the development of modern geosciences. It reveals the mechanism of a series of earth processes by linking together the phenomena that used to be considered as irrelevant. It has improved traditional models, and provied new possibilities in prediction of various resources and environmental problems. It has not only contributed to the great achievements of Global Change (IGBP)study, but also penetrated into all fields of geosciences and changed their traditional approaches of research. The Earth System Science is characterized as: (1)linking and revealing mutual effects of the Earth’s phenomena that happened far away to each other; (2)merging the internal agencies and external agencies into an integral whole; (3)merging the geological and biogenic processes into an organic whole; (4)regarding the human activities as a part of Earth’s system. New development of Earth System Science has also faced some problems: (1) an overlook on geological processes. In the biogeochemical system, geological processes are always regarded as long term cycles comparing with the biologica1, atmospheric, and hydrological processes. Consequently, geological processes are not sufficiently addressed in different global change models, or given a parameter 1-2 order of magnitude lower than other processors; (2) incomplete in the monitoring system. For example, in the 10 core projects of IGBP, the monitoring of geological processes is completely ignored; (3) the Earth System Science approaches have not penetrated into the fields of microenvironment and studies of resources formation. The recent field experiment and monitoring on some typical sites have demonstrated that geological processes are not necessarily all long-term cycling. Some of them are actively involved in modern global biogeochemical cycles. A better estimation of the geo logical processes could be a way to solve the problem of inbalance in the available global change models.

STRIP-SHAPED TECTONIC DIVIS10N 0F C0NTEM P0RARY LITH0SPHERIC STRUCTURE 0F EASTERN CHINA

Ma Zong-jin, Wang Guo-quan

1999, 5(1):  7-16. 

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Separated by the Yinchuan-Kunming line(105°± 2°E), the eastern and western parts of the China continent are different sharply from each other in lithospheric structure as wel1 as in other features. These two parts can be further divided into many secondary tectonic units according to features of mountains and rivers, neotectonic faults, earthquakes, gravity, thickness of earth crust, geomagnetic anomaly and high-conduct layers. In this paper, based primarily on the features of earthquake intensity and frequency, as well as a comprehensive analysis of data about the preferred arrangement direction of epieentra1 density, strikes of mountains and rivers, neotectonic faults, gravity, geomagnetic and high-conduct layes, we divide the eastern China into seven secondary tectonic units: North-Fast(north)region, North-Fast(south)region, large North China region, Central China(Middle and Lower reaches of Yangtze River)region, South China (north)region, South China (south)region and South Chin Sea region. The south boundaries of each secondary tectonic unit are respectively 47°N tectonic 1ine. Yinshan tectonic belt, 34°N tectonic line, Beiling tectonic belt, Nanling tectonic belt and 20° N tectonic line. The basic features of these regions are characterized by nearly west-east trending, with an width about five degrees of latitudes, parallelly ranging, and great differences in lithospheric structure, history and intensity of tectonic deformation. We name them as the strip-shaped tectonic regions. reflecting the subdivision of eastern China. If regarded as a part of secondary tectonic of south-east region of Eurasian continent plate, they can be analogized with a series of parallel suboceanic strip-shaped tectonics of the Fast Pacific Ocean and the Atlantic Ocean, which were caused by suboceanic transform faults. These suboceanic strip-shaped tectonics have very small differences in 1and features. But these strip-shaped tectonics in continental plate are more complicated, because they are different from each other in evolutionary history and physical composition. If these EW-striking continental lath-shaped units have been affected by the force from the Pacific plate, i.e. from east or nearly east since the later Mesozoic, then the active mode is a parallel active mode corresponding to the striking of lath, shaped unit, and the mode is favorable to bring about differential deformation caused by their own difference. In eastern China, shallow morphostructure deep structure of crust and lithosphere, as wel1 as the high conduct-layer, all resulted from the merging of the early Mesozoic continents and intensive deformation of the late Mesozoic continents. The main tectonic direction controlling the whole region is the NE-striking, and the NE-striking and NW-striking tectonics conjugate with each other. A series of en echelon morphostructures developed in the boundary area between every pair of secondary region, which was caused by relative movement of the secondary units. In this paper, based oil the features of 1oeation an d stretch, we name Wuling Mountain, Mufu Mountain, Jiuling Mountain, Huaiyu Mountain and Xianxia Mountain, etc. as a whole the Beiling Mountain belt corresponding to the name of the Nanling Mountain belt. The Beiling Mountain belt is the boundary between south China(north)region and centra1 China region.

SIGNIFICANCE OF DIM ENSION VALUE D OF FAULT SYSTEMS IN EVALUATING NATURAL RESOURCES WITH TIBET AS AN EXAMPLE

Li Ben-liang, Zhang Xi-hui, Sun Yan, Lu Xin-wei

1999, 5(1):  17-21. 

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The principles of fractal geometry and method of box-counting dimension have been used to calculate the fractal dimension value D of fault systems in three oil-gas prospecting areas (Qiangtang, Biru, Cuoqin) and an ore-deposit prospecting area (Sanjiang) in the Tibet region. The values were then compared with those of the oil-gas area in Sichuan, ore-deposit areas in Dexin, Jiangxi province and in central Hunan province respectively. It has been found that the dimension of fault systems in the oil-gas hearing areas is l 1.80, larger than that of the whole region. The larger the dimension, the larger the scale of ore-deposit. The results of this study suggest that it is hopeful to find certain oil-gas fields in the Qiaiagtang and Biru prospecting areas, and high-grade ore-deposit in the Sanjiang prospecting area.

STUDY ON THE Nd-Sr ISOTOPIC COM POSITIONS OF GRANITOIDS IN SE CHINA

Shen Wei-zhou, Ling Hong-fei, Li Wu-ian, Huang Xiao-long, Wang De-zi

1999, 5(1):  22-32. 

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Nd-Sr isotopic compositions of 58 granitoid bodies in SE China are reported in this paper. Based on these data and previously published isotopic compositions of other 127 granitoid bodies and comparison with Nd isotopic compositions of basement metamorphic rocks, we studied the Nd-Sr characteristics of granitoids of various ages in SE China and their sources. The Palaeoproterozoic grantoids are only distributed in southeastern Zhejiang province within the Cathaysia Block. These granitoids have εNd: -6.2 to-3.0 and initial 87Sr/86Sr ratio (Isr) of 0.7083 to 0.7l17. On the εNd-t diagram they are plotted within the evolution zone for the Palaeoproterozoic metamorphic rocks in the same region. This suggests that these Palaeoproterozoic granitoids be formed by partial melting of rocks similar to the Palaeopmterozoic metamorphic rocks. The Neoproterozoic granitoids in SE China are distributed in the southeast margin of the Yangtze Block. The Neoproterozoic granitoids distributed along the Jiang-Shao Fau1t Zone have high εNd value (2.0 to 4.2), low Isr value(0.7011 to 0.7032) and low δ18O value(6.3 to 6.7‰) which are similar to those of middle Proterozoic spilite-keratophyre of Shuangxiwu Group. Therefore, these granitoids may have been derived from a mantle source similar to the source for the spilite-keratophyre, or from partial melting of juvenile crust consisting mainly of spillte-keratophyre. The Neoproterozoic granitoids in western Zhejiang, southern Anhui and northern Jiangxi provinces have εNd: -0.4 to -2.2, Isr=0.7040 to 0.7064 and δ18O=10.5 to 11.7‰. On εNd-t diagram, they are plotted in upper part of the evolution zone for the middle Proterzozic metasediments of the Shangxi Group and Shuangqiaoshan Group. This suggests that they be derived from the low maturity components of basement metamorphic rocks in this region. Almost all Paleozoic granitoids are distributed in the Cathaysia Block. They have variable isotopic compositions (εNd= -18.1 to -2.1, Isr=0.7071 to 0.7287). On εNd-t diagram, most granitoids are plotted within the evolution zone for the middle Proterozoic basement metasediments, suggesting they be derived mainly from crustal materials. Mantle component was involved in formation of sonic Paleozoic granitoids. Mesozoic granitoids are distributed all over SE China. Their isotopic compositions are evidently variable(εNd=-16.4 to 1.9, Isr=0.7043 to 0.7404). On εNd-t diagram, more than half of the granitoids are plotted above the evolution zone for the middle Proterozoic crust in the region, indicating their crustal derivation. However, many granitoids mainly distributed at the coast of Zhejiang and Fujian provinces are plotted above the evolution zone for the middle Proterozoic Crust in the region, suggesting more mantle-derived materials in their sources. These granitoids may have been formed by mixing of the basaltic magma induced by subduction of the Pacific Plate in the late Mesozoic era with the felsic magma formed during partial melting of crustal rocks caused by underplating of basaltic magma.

STUDY ON THE RESIDENCE STATE AND DISTRIBUTI ON REGULARITIES OF GOLD IN YUESHAN Cu-Mo DEPOSIT, ANQING WESTERN ANHUI PROVINCE

Yang Xue-ming1;2, Yang Xiao-yong1;2, Wang Kui-ren1;2, Lin Xiu-qing3, Wang xian-jue3, Zhang Yu-liang4

1999, 5(1):  33-43. 

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In this paper the forms of existence and distribution regularities of gold in Yueshan Cu-Mo ore deposit, Anqing, western Anhui Province, are studied by means of optical microscope, chemical analysis, electron microprobe, and proton and nuclear microprobes in PIXE system etc. It shows that the gold in the copper deposit mainly occurs in micro-grained native gold of independent minerals including silver-bearing gold, silver gold and natural gold, which are concentrated in quartz vein type copper ore, copper-bearing calcite veins and diorite type copper ore. They’are associated with chalcopyrite, pyrite, bornite, molybdenite and quartz. The gold-silver mineral series is mainly composed of native gold, whose grains range from 0.15to 0.30 mm, with a maximum size of more than 0.5 mm. The intensity of gold mineralization varies with the depth of the ore body; the gold grade in the upper part is higher than that of the lower, whereas the degree of variation of gold grade in the horizontal direction is less than in the vertical direction. This study provides an evidence for the comprehensive use of the accompanying gold in the Cu-Mo ore deposit in this region.

GENETIC SIGNIFICANCE OFHIGH-TEMPERATURE EXPERIMENTS ON IGNEOUS ROCKS

Zhou Xun-ruo, Bai Zhi-min

1999, 5(1):  44-53. 

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This paper puts emphasis on the genetic significance of some high-temperature experiments with volcanic rocks, intrusive rocks, meteorites and dark hydrous minerals as initial experimental materials．On the basis of layering of the melting crust of chondrite and the glass，a discussion is made on the layer structure of terrestrial planet and the forming mechanism of volcanic rocks during the early period of the earth and moon rocks．On the basis of the melting sequence of minerals from acidic volcanic rocks during dry melting and wet melting，an analysis is made on the acidity evolution of granitic magma during intrusion and the genesis of light-colored granulite．In addition，a discussion is also ma de on the relation of melting point，acidity and structure of rocks．According to the melting experiments of basalt with added granite，the authors exclude the possibility of formation of leucite basalt through assimilation of basaltic magma by granitic magma，and suggest the possibility of forming tholeiitic series rocks with Large straddle trend through fractional crystallization of high-aluminium basaltic magma and alkali picritic magma．By calculating the viscosity of melt at different acidities and different temperatures，the authors illustrate the relationship between the acidity, viscosity of melt and volcanic phase，eruption and volcano types，and point out that at the same temperature，the larger the acidity，the higher the viscosity increasing rate. The correlation is made between the melting experiments of fresh basalt and basalt with weak spilitization, metamorphism and weathering. It proves that the compositions of these rocks，as long as their original microstructures are preserved, can be taken as the criteria for rock type and series classification and rock nomenclature. By using the method of basalt melting-crystallization experiments, the relationship is studied between the course of mineral crystallization，the degree of supercooling, the nucleation of melt and the growth rate of crystals. The mineral assemblage and evlution sequence as well as their significance are investigated during the cooling course of leucite picritic melt. According to the heating experiments of dark hydrous minerals，an interpretation is given to the course of their changes such as oxidation，dehydration and thermo-optical characteristics, and to their stages of changes such as darking, resolution and melting. A discussion is made on the application of these results to geothermometer and phased division of igneous rocks. The pressure effect and quenching effect of calcium-rich clinopyroxene is also studied especially its changes in TiO2 and A1203 contents. The authors point out that isothermal effect may exist for calcium-rich clinopyroxene.

K-Ar ISOCHRON DATING OF KULUKTAG MAFIC DYKES, XINJIANG AUT0N0M0US REGION, AND DISCUSSION ON SOME RELATED QUESTIONS

Liu Yu-lin, Zhang Zhi-cheng, Guo Zhao-jie, Huang Bao-ling, Mu Zhi-guo

1999, 5(1):  54-58. 

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There has been increasing interest in the study of dyke swarms which are related to rifting and continental break-up. Ku1uktag dyke swarms are located in the northeast part of Tarim Basin, Xinjiang, China. The dykes, parallel to each other, intruded into the Archaean and early Proterozoic rocks. Four samples collected from the dykes are dated with K-Ar method. The apparent ages are discordant, ranging from 455 to 673 Ma. Using the Ludwing’s ISOPLOT, an isochron age of 287± 13 Ma was obtained with a correlation cotfficicent of 0.9850, This age is concordant with the ages of volcanic rocks along the Tianshan Mt. structure zone dated around 280Ma. The K-Ar isochrom method has some advantage for dating mafic dykes：(1)These rocks are often fresh and slightly affected by alteration; (2) The closure temperature of mafic rocks for argon is high; (3) The measurement precision of mass spectrometer is much higher than it was before, so that low K samples can be well measured; The potassium abundance of mafic dykes is about 0.5-1.5％ and suitable for K-Ar dating; (4) The whole rock method is used, so that the tough work of selecting monomineral fraction is not necessary. Moreover, the initial argon can be eliminated by this method, but the atmospheric argon must be removed in the experimental process. Igneous rocks originated from different sources have different initial argon ratios. The initial argon ratio for Kuluktag dykes is 508, belonging to mantle plume-type according to Kaneoka and Takaoka(1985). We infer that the magma of the dykes originated from “enriched mantle”. The REE and trace elements features of the dykes am also typical of “enriched mantle” and are in good agreement with those of basalts related to plume.

APPLICATION OF MULTIDIMENSIONAL SELF-AFFINE DISTRIBUTION IN GEOCHEMISTRY

Shen Wei

1999, 5(1):  59-65. 

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The fractal was founded by Mathematician B.B.Mandelbrot. A fractal is an object made of parts similar to the whole in some way, either exactly the same except for scale or statistically the same. The fractal geometry deals with irregular phenomena or objects in nature, such as topographie relief, fracture strength of rocks, earthquake magnitude etc. It is difficult to describe them by classic mathematical methods. But there is a common characteristic among these phenomena or objects-self-similar. Fractal dimension measures the degree of irregularity based on self-similarity, and is also a numerical index that quantifies the self-similarity of complex phenomena. The character of self-affine fractal is the anisotropic of fractal body n alteration, that is, the different directions have the dissimilarity of scale factor, while self-similar fractal is the special case of self-affine fracta1, that is, the different directions have the homology of scale factors. This paper advances the conception of the multidimensional self-affine distribution points out that the multidimensional self-affine distribution is the mathematical base of the multidimensional self-affine fractal, proofs that the multidimensional self-affine distribution possesses the fractal property of scale-free under truncation and expands the theoretical study of fractal on multidimensional case. Then the paper explains the method and procedure of the multidimensional self-affine distribution in application and real meaning of fractal dimension by examples. The fractal dimension can be regarded as the parameter to reflect the variety degree of region variable on certain direction. The method not only is applied to Au data and Ag data but also suits other geochemical element data or geological data and has general meaning. We expand the theory of fractal to multidimensional case and can study the change courses of the fractal system, i.e., establishing the theoretical system of fractal dynamic mechanism.

RE-DIVISION OF THE METAMORPHIC FACIES Z0NATION 0F LULIANG GR0UP IN SHANXI PR0VINCE AND ITS SIGNIFICANCE

Yu Jin-hai, Wang Ci-yin, Lai Min-Damn, Chen Shu-qiang, Lu Bao-qi

1999, 5(1):  66-75. 

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Luliang Group underwent at least two metamorphic and deformation events in the Precambrian. The early geological event is characterized by a weak metamorphism and strong deformation. It caused a tight folding of Luliang Group strata with nearly N-S direction However，its metamorphic grade is only greenshist facies. The late geological event is featured by a stronger metamorphism up to high amphibolite facies. It is described as the main metamorphic event and has obvious zoning. Metamorphism increases gradually from the North to the South. The orientation of main metamorphic zones is almost vertical to the strata strike. At 1east five different zonation patterns were proposed during past twenty years. This paper set up a new subdivision of the metamorphic facies zonation of the Paleoproterozoic Luiang Group on the basis of the detailed field mapping and petrographic study. All five zones，the chlorite zone，the biotite zone，the almandine zone，the staurolite-kyanite zone and the sillimanite zone，are distributed from north to south successively. The former four zones are the products of the middle pressure facies series, similar to the typical Barronian metamorphic zones，and the fifth sillimanite zone was formed at lower pressure. Sillimanite results from the reaction of St+Ms+Q=Si1+Bi+H2O. The main metamorphism event overprinted and reformed distinctly the early event marks. In addition, the late tectonic-thermal event led to wide migmatization to the area south of Xichuanhe fault. Surveying shows that the main metamorphism is closely related with the Xichuanhe thrust fault activity. The nearly N-S compression an d thrusting and the heat from depth resulted in the main metamorphism and migmatization. The main metamorphism of Luliang Group is a part of the whole structure-metamorphism-magmatism activity of the central part of North China. U-Pb dating of zircon indicates that it occurred at 1800±Ma，namely the Luliang orogeny.

ON THE PERMIAN PHYTOGEOGRAPHY OF W.HENAN-N.ANHUI REGION

Wang Jun1, Sun Bai-nian2, Shen Guang-long3

1999, 5(1):  76-91. 

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Statistica1 method has been used in a comprehensive study of the Permian focal1 plants from W.Henan-N.Al1hui region. The results of this study are summarized in the attached table and compared to the fossil plants from North and South China. Four Permian plant assemblages have been recognized in this area，which are: (1)Neuropteris pseudovata-Lepidoderdron szeianum assemblage in the early stage of the Early Permian (the middle and upper parts of Taiyuan Formation) (2)Emplectopteris triangularls-Cathaysiopieris whitei-Lobatannularia sinensis assemblage in the middle stage of the Early Permian (the Shanxi Formation) (3)Gigantopteris lagrelii-Lobatannularia ensifolia-Fascipeters hallei assemblage in the late stage of the Early Permian (the Lower Shihhotse Formation). (4)Gigantopteris nicotianaefolia-Lobatannularie multifolia-Psygmophyllum multipartitum assemblage at the early stage the Late Permian (the Upper Shihhotse Formation). The major components of each p1ant assemblage are compared quantitatively in the Figure 1. The Permian flora of the W.Henan-N.Anhui region is characterized by its endemic features, especially in the late stage of the Early Permian and the early stage of the Late Permian. However，as far as the number of species is concerned, the species occurring only in the W.Henan-N.Anhui region are usually less than those occurring both in this region and N.Chian，i.e.，A≤B+C. Therefore, this region could be regarded as a phytoprovince in the N.China Phytoarea，rather than a phytoarea with the same rank as N. China and S. China regions. This conclusion is further supported by an analysis of thecommon species and the Simpson coefficients (see table 1) among these plant assemblages in the W.Henan-N.Anhui region，N.China and S.China，because the fossil flora of W .Hena n-N.Anhui region generally possess a closer relation to that of N.China than S.China throughout Permian period. As an independent phytoprovince in the N.China Phytoarea，the fossil flora in this region possesses certain transitional features be tweed the flora in N.China and S.China Phytoareas. For example, Gigantonoclea and Gigantopteris, which are considered respectively the representative as member of the Gigantopterids in N.China and S.China, co-exist primarily in the W.Hen an-N.Anhui region. The development of the W.Henan-N.Anhui phyroprovince is probably related to the movement (drifting, rotating)of the N.China and Yangtze blocks and is consistent with the Permian coal beds containing this fossil flora and bearing the feature of “northern stratigraphic type and southern sedimentary facies”.

STUDY ON CAP BEDS OF SHALLOW BIOGENIC GAS POOLS IN LATE QUATERNARY DEPOSITS OF SOUTHEAST CHINA COASTAL PLAIN

Lin Chun-ming1, Wang Yan-zhou2, Huang Zhi-cheng1, Qian Yi-zhong3

1999, 5(1):  92-99. 

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Based on experimental data of mechanical and physical properties, hydrocarbon concentration, as well as field test of pore-water pressure and its disappearing time, a comprehensive investigation has been conducted to study the cap beds and its sealing mechanism in shallow biogenic gas pools of the Late Quaternary in the Southeast China coastal plain. The result of this study has indicated that the gas-generating beds above the reservoirs could he considered as the cap beds. The gas cap beds in this area are primarily grey mud deposited in inner sublittoral environment and grey-greyish black mud deposited in fluvial flood plain environment. The grey mud usually occurs above the incised valleys formed in the last glaciation (such as Qiantangjiang incised valleys) and could be considered as the regional cap beds, while the grey-greyish black mud occurs only within the incised valleys and forms a local cap beds. Such parameters reflecting physical properties of sediments as the porosity, pore ratio, natural water 0ontent and pore-water pressure are related to specific surface area of particles in the sediments. The smaller the grain size is, the larger the parameter values are. Therefore, the parameter values increase successively in fine silt, silt, siltic clay and clay. As for the petro-mechanical properties , the clay has not only the largest compressibility coefficient, plastic and liquidity indexes, as well as the shear strength, but aim the weakest deformation-resistance and volumetric deformation. Consequently, the clay is the best sealing layer comparing with the silt mud and silty day. The sealing ability of the cap beds increases with its buried depth. Although the sealing mechanisms of the cap beds include physical and hydrocarbon concentration sealings, the pore-water pressure sealing probably is the most important mechanism in the shallow biogenic gas field.

STUDY OF MECHANISMS OF THE “OVER-COVERED TILES” STRUCTURE IN SLOPE DEF0RMATI0N OF XIAO LANGDI OF YELLOW RIVER

WANG Bao-jun1, CHEN Zheng-zhou, Li Qin-bo2, Wang Yong-qiang

1999, 5(1):  100-104. 

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Based on the engineering geological conditions，the forming mechanism of the “over-covered tikes” structure，widely developed in the Xiao Langdi area of Yellow River，has been analyzed with the methods of mechanics and geology．The results of this study suggest that the relationship between this peculiar structure and landslide could be summarized as follows: 1. Instead of being the cause of landslide．the “over-covered tiles” structure in the Xiao Langdi area is the result of long-term slope creeping caused by slope deformation． 2．The structure in this area wan formed under such engineering geological conditions as interlacing of soft and hard rock stratum，long term creping deformation of slope． 3．Since the “over-covered tiles” structure is a phenomenon caused by long-term creeping deformation of slope in the course of landslide deformation，it could be used to predict and analyze the forming mechanics of landslide．In other areas where this structure is developed，if their engineering geological and hydraulic geological conditions are similar to those in the Xiao Langdi area，the possibility of creeping landslide should be considered．

PAST IS THE KEY TO THE PRESENT: METHOD OF HISTORICAL GEOLOGY IN ENVIRONMENTAL SCIENCES

WU Tai-ran, GUO Zhao-jie, MU Zhi-guo, PAN Mao, CAI Yong-en, HE Guo-qi

1999, 5(1):  105-109. 

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The principle that “the present is the key to the past”, which has lead the geology acquired tremendous achievements, is and will continue to be the most important thought in the development of earth science．The problems on resources, environment and calamity that human society will face to in the 21 century are fundamentally the problems of geology. To be prepared for the new challenges, the geologists must change their way of thinking in geological research. If we recognize that evolution of the Earth in the history was in a way similar to that of today, the new principle that “the past is the key to the present and future” will become more and more important in the earth science. From the perspective of historical geology, study of the processes of geological events happened in the earth history, their evolutionary trends and environment impacts in the past and future, will be a major task of geology in the 21 century.

DO THERE EXIST SEA-FLOOR VOLCANIC ERUPTIVE SEDIMENTS IN THE HUANGLONG FORMATION, TONGNING XINQIAO AREA, AUHUI PROVINEC

Huang Zhi-cheng

1999, 5(1):  110-112. 

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SILICEOUS LIMESTONE OF HUANGL0NG FORMATION IN THEAREA BETWEEN WESTHERN ZHEUIANG AND S0UTHERN ANHUI

Shi Gu-gun, Yang Xiang-ning

1999, 5(1):  113-114. 

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PIECES OF POTTERY FROM LATE PLEISTOCENE SALAW USU FORMATION IN QINGYANG DISTRICT, GANSU PROVINCE

YUAN Xiao-qi1, MIN Qi1, YANG Jun-jie1, GUO Zhong-ming1, LIU Guan-bang2

1999, 5(1):  115-115. 

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Piece of pottery had not been found previously from the sediments of 10000 years old in China and abroad．During a research of the Quaternary stratigraphy in Qingyang district, Gansu Province, some pieces of pottery have been discovered from the upper silty clay layer and basal gravel bed of the Salawusu Formation．In the some horizon, many mammalian fossils and human cultural remains, such as the palaeoliths, ashes and charcoal bits, have also been found．Among the mammalian fossils are such taxa as Palaeolarodon naumanni, Coelodonta antiquitatis, Eqnns prsewalskyi, Crocuta ultima, Megaloceros ordosianus, Spirocerus kiakhtensis, Ovis ammon, Bos primigenius etc., which are typical for the Late Pleistocene．14 C dating for the calcareous nodule of the upper part of Salawusu Formation at Shilipodi of Jiaozichuan in Qingyang suggests a age about 25 290±500aB.P.,which is consistent with the geological age indicated by the mammalian fossils．Therefore, the age of these Pieces of pottery discovered in the Salawusu Formation should also be the Late Pleistocene．The new discovery suggests that the history of human pottery-making could be further traced back from about 10 000 years ago to about 30 000 years ago．