Abstract:On the basis of abundant geological and geophysical data. 6 terranes have been distinguished on theQinghai-Tibet Plateau. The plateau is a single integrated lithospheric unit although it is divided into blocks.With Amdo as a boundary. the crust may be divided into two parts with different crustal structures. The struc-ture in the southern part is complex, while that in the northern part is simple. The current study has revealedthat 8 factors such as slab subduction. overthrust and superimposition are responsible for crustal shorteningand thickening in the region. The uplift of this region is possibly due to northward compression of the Indianplate and southward compression of the Eurasian plate with the former predominating. The compression led tothe asthenospheric movements which were also influenced by thermal activity caused by doming at the bound-ary between the core and mantle.

Abstract:This paper studies. for the first time, the storm deposits of a carbonate sequence in the Sinian ZhangquFormation in northern Anhui. In the formation. a great number of calcareous trider sponge spicules were dis-covered in a distal storm turbidity sequence, which have provided further evidence for the correlation of theSinian Systems in North and South China from a view point of palaeontology.

Abstract:Apatites occurring in sedimentary rocks are carbonate fluorapatites (C-F apatites) with differentCO_2 contents. During diagenesis. the CO_2 in the C-F apatites gradually decreased with the increasing strengthof diagenesis. resulting in the systematic changes in refractive index. specific gravity, cell parameters and crystalchemistry of apatites. On the basis of X-ray diffraction and IR spectroscopic analyses, the author proposes twoparameters for determining diagenetic stages. i.e.. the crystallinity index (CR) and sharpness index (SH). Thesetwo parameters serve as new criteria for the determination. which due to the common existence of phosphorousnodules and bands and argillo-crystalline cement in sedimentary rocks, most likely have wide prospects for ap-plication.

Abstract:Owing to the internal relationship between material sources or mineralization ways and the difference ofmineralization micro-environments or the change of constraints. certain types of nonmetallic mineral depositsare regularly formed either simultaneously or in successive order under the control of certain association ofmineralization processes in a certain geotectonic environment, thus forming a minerogenetic series ofnonmetallic mineral deposits. The geological setting that controls the formation of minerogenetic series is mosttruly recorded in ore-bearing formations. while the mineralization processes which are associated or surely suc-cessive are the indispensable prerequisite for the formation of the various mineral deposits of a minerogeneticseries. Therefore, the minerogenetic series of nonmetallic mineral deposits can be classified according tomineral-bearing formations and mineralization processes. Based on available data. 13 minerogenetic series aredistinguished in China. The study of minerogenetic series may not only result in the enrichment of the theory ofmineral deposits but also help direct mineral prospecting and give guidance in the integrated development andutillization of mineral resources.

Abstract:The pre-Sinian basement on the southwestern margin of the Yangtze paraplatform consists of threemetamorphic rock series of different ages. Being products of different tectonic events and environments, theydiffer markedly in original rock sequences, metamorphism. tectonic style and characteristics of granitoids andmineral deposits. The Late Archean Kangdian cration mainly comprises the Kangding and Julin Groups with ametamorphic age of nearly 2500 Ma. They are supracrustal rocks dominated by mafic volcanics enclosed introndhjemitic rocks The craton is believed to represent a granite-greenstone terrane of Late Archaean age.There occur mineral deposits such as graphite and kyanite deposits of metamorphic origin, muscovite depositsin pegmatites and gold quartz veins in gneissic granites, banded hornblende-magnetite mineralization and cop-per and zinc mineralizations related to felsic volcanics. Large V-Ti-bearing magnetite deposits were also formedin the mafic. ultramafic stratiform intrusions emplaced on the margins of the craton during the MiddleProterozoic. Copper and nickel deposits are found in several ultramafic intrusions. Extending in a north-southdirection, the Proterozoic mobile belt consists mainly of the Early Proterozoic Hekou Group and MiddleProterozoic Huili and Kunyang Groups. and they are thought to be accumulations in a Proterozoic rift troughor aulacogen. During the Early Proterozoic, the rift trough was characterized by intense volcanism and pres-ence of iron ore deposits of volcano-magmatic type, iron-copper deposits of exhalative-sedimentary type. TheMid-Late Proterozoic of the rift trough mainly witnessed the formation of sedimentary stratiform copper de-posits and submarine sedimentary iron deposits. In the wake of the emplacement of the Jinningian andChengjiangian granites in the Late Proterozoic, skarn-type tin and tin-iron ore deposits were formed.

Abstract:Warm and humid climate and gentle hilly topography have provided favourable conditions for the devel-opment of the weathering crust of the granite intrusions in the Longnan area, Jiangxi Province. REE is mostlyconcentrated in an adsorption state in clay in the wholly weathered zone. The rare-earth minerals enriched inthe parent rocks provided the source material for the REE enrichment. Exchangeable REE accounts for48-86%. Extraction experiments and stable isotopic study of clay minerals suggest that the downward infiltra-tion of meteoric water and increasing gradient of pH values have played an important role in the enrichment ofREE during the progressive weathering. Slight fractionation of individual REE can not change their distribu-tion patterns in the profiles. which are inherited from the parent rocks.

Abstract:Based essentially on research results of calcareous nannofossils, combined with some other microfossil da-ta and several secondary depositional breaks, this paper discusses the criteria of division and comparison of themiddle and late Tertiary marine sediments, palaeogeographical and palaeoenvironmental evolution andpalaeoclimates on the northern continental margin of the South China Sea, comprising the Tainan basin, PearlRiver Mouth basin. Southeast Hainan basin and Beibu Gulf basin. Study shows that the upper Oligocene toPliocene strata in the whole area consist essentially of marine sediments except in the Beibu Gulf basin. Theyinclude littoral. neritic and deltaic sediments as well as carbonate rock-bioherm limestone. The sea advancedfrom southeast to northwest. During the transgression there appeared three culminations coinciding to thestages of deposition of nannofossil zones NN4-5, NN11 and 13-15.

Abstract:Based on the Rb-Sr isotopic study of the granitoids in the Hengduan Mountains, the classification andgeologic significance of whole-rock Rb-Sr isochrons as well as the factors influencing homogenization of theisotopic systems are discussed. Usually. there is no good linear correlation of isochrons for diorites andalkali-rich intrusive rocks (including alkaline rock and alkalic granite). But by means of the external isochron ofmonominerals from the rocks. isochrons with good linear correlation as well as ages and Sr initial ratios with ahigh confidence can be obtained. In order to obtain a satisfactory isochron, the discriminant parameters shouldbe calculated from the Rb/Sr ratios and estimated ages of samples. Only those that meet the requirements canbe used as the Rb-Sr isochrons. The quality of an isochron should be judged from three factors, i.e. correlationcoefficient. MSWD and homogenization degree.