The Lower Cretaceous in northern Himalayas mainly consists of clastic rocks. The submarine fans were well developed in this area. According to the minerals, textures,structures and occurrence of sedimentary rocks, the submarine fan can be divided into six subfacies. The subfacies and thier arrangements and combinations indicate various sedimentary environments. The evolution of the submarine fan can be divided into the embryo stage, young stage, peak stage, and the waning stage. The embryo and young stages were developed during the Early Age and Middle Age of the Early Cretaceous. The sand/mud ratio of sedimentary rocks are much higher than any of other stages. The sedimentary rocks are mainly sandstones with different minerals and textures. It means that the costal plain and shelf was very narrow and the sea floor was steep. The sedimentary environment was changed from shelf to slope. Major tectonic movements were extension, split and subsidence. During the Late Age of the Early Cretaceous, the submarine fans were in peak stage. Coastal plain and shelves were much wider than before. Sedimentary rocks were black shale and finegrained clastics with very large thickness. There are many siderite and calcic nodules and a few ammonite fossils in black shales. The ratio of sand/mud of sedimentary rocks is lower than any of other stages. The sedimentary facies changed slowly in this area. The sedimentary conditions belong to low energy, gentle slope without obvious slope breaks of continental margin. These characteristics indicate the significant marine transgression events in northern Himalayas.  As a result of the Indian Ocean spreading and the Indian Plate moving to the north during Early Cretaceous, the passive continental margin was well developed here. The sedimentary environment was transformed into bathyal and abyssal environments. Due to the marine regression, submarine fans evolved into waning stage in the Late Cretaceous and sedimentary rocks changed from shales to coarse sandstones even conglomerates. The sedimentary basins developed stage by stage from shelf to extension basin to slope, and at last to deep sea basin during the Cretaceous.

The Nanpu Sag is located in the northern Huanghua Depression in the Bohai Bay Basin. The Guantao Formation of Neogene in the Sag is the important petroliferous stratum for oil and gas exploration. The sedimentary facies of the Guantao Formation of Neogene are chiefly braided rivers except that the facies are meandering rivers in the middle segment of the Formation. It is the key problem for oil and gas exploration of the Formation to forecast the distribution of advantageous caprocks and to correlate high quality reservoir sand stones accurately.  Based on the principle of high resolution sequence stratigraphy and on the information about lithologic log and welllogs, the author analyzed the patterns of the sequence stratigraphy, the features of sedimentary facies and the combinations of reservoirs and caprocks of the Guantao Formation. The result indicates that the Guantao Formation has developed two kinds of shortterm baselevel cycles which are respectively unsymmetrical cycle formed in low accommodation and symmetrical cycle formed in high accommodation, and four mediumterm baselevel cycles ,which are two unsymmetrical cycles being chiefly half cycles of base level elevating(MSC1, MSC2), one symmetrical cycle(MSC3) and one unsymmetrical cycle being chiefly half cycle of base level descending (MSC4). And both shortterm baselevel cycles and mediumterm baselevel cycles are mainly unsymmetrical ones. During the longterm baselevel cycle of the Guantao Formation,the baselevel elevated slowly and then descended quickly. From MSC1 to MSC4, the sedimentary system of the  Formation has changed first from the combination of alluvial fans and braided rivers to the combination of braided rivers and meandering rivers, then to the combination of meandering rivers and braided rivers. From north to south,while the accommodation of each mediumterm baselevel cycle becomes gradually large, the principal sedimentary facies have gradually changed from gravel channels to sandy channels. Controlled by the framework of mediumterm baselevel cycles,the Guantao Formation in Nanpu Sag  has developed three sets of combinations of reservoirs and caprocks. The upper combination, of which the reservoir and caprocks are the most advantageous, should be the most important target bed of the Guantao Formation in Nanpu Sag for oil and gas exploration.

Based on comprehensive study of cores and various data,the author considered that the sandstones and oolitic limestones in the Middle and Upper Ordovician of Well TZ32 in the Tarim Basin were mainly origin of internaltide deposits. The thickness of Middle and Upper Ordovician drilled in Well TZ32 is 1 462 m and mainly composes of alternating beds of darkgray mudstones and/or shales and gray sandstones and/or siltstones interbedded with minor limestones,in which darkgray mudstones and/or shales are the most. Sandstones and siltstones are mainly concentrated in the upper and lower part. Oolitic limestones are rare and interbedded in darkgray mudstones and/or shales. These sandstones and oolitic limestones can form beds alone,but more commonly,form thin alternate beds with drakgray mudstones and/or shales in which flaser,wavy and lenticular bedding are welldeveloped,and cross bedding and bidirectional cross laminations are also welldeveloped. According to the sedimentary background and the characteristics of lithology and sedimentary structure combination,these sandstones and oolitic limestones are explained as the products of internaltide deposits on deep water slope. These internaltide deposits can be classified into four basic types according to their features,i.e.,bidirectional crosslaminated finegrained sandstone,unidirectional crossbedded and bidirectional crosslaminated mediumgrained to finegrained sandstone,rhythmic thin alternating beds of sandstone and mudstone,and oolitic limestone. These internaltide deposits possessed five types of vertical successions and formed rhythmic deposit combinations with cyclicity in the vertical section.

In different ages， due to difference in burial depth and in oxidation-reduction conditions of diagenetic environments， the cements precipitated are different in character. In some cases, precipitation of cements of different generations is continuous, and the contact between two generations of cements is conformable. But in other cases, precipitation process is once interrupted by dissolution, and the contact between two generations of cements is unconformable. Some pores and fissures form early, and generations of cements in them are many and complete. But some pores and fissures form late, and some generations of cements are missing. Thus, cements can also be divided and correlated like strata. Thereby, change of diagenetic environments can be analyzed, and time of pore and fissure formation can be inferred. As change of diagenetic environments is commonly related with structural movements, time of structural movement can also be inferred through study of cement stratigraphy. In  Ordovician carbonate rocks of the Qianmiqiao area of the Huanghua Depression, pores and fissures are filled with 5 generations of cements. Each generation shows different color of cathodoluminescence. Between the second and third generations of cements there exists dissolution unconformity. Based on characteristics of cements, 5 times of fracturing can be recognized, which occurred in the Triassic, middle-late Cretaceous, end of Paleogene and end of Neogene.

The basic principle and method of 3D stochastic modeling of sedimentary microfacies are discussed according to geological and acoustic impedance data of welllogging constrained seism inversion,and a case study according to stochastic modeling of fluvial facies reservoir of the Minghuazhen Formation of Neocene in a certain block of Bohai Bay Basin is used to show the general process of this research. The general process of this study includes sedimentary microfacies interpreting within boreholes,welllogging constrained seismic inversion,probability relation analysis between acoustic impedance and sedimentary microfacies,selecting the method of stochastic modeling,analysis of geological statistical characteristics,3D stochastic modeling and assessment to multisolutions of forecasting of stochastic modeling.The results show that there are some correlative probability relations between acoustic impedance and sedimentary microfacies,and the stochastic modeling of sedimentary microfacies can make an effective assessment to multisolutions of reservoir forecasting by synthetically applying multidisciplinary information,including seismic data.

Pelecypoda unearthed from the Neolithic Xishuipo Site of Puyang City，Henan Province are studied in this paper 31 species among 33 species recognized compose the LamprotulaCuneopsisUnio assemblage which has been known as the Xishuipo Lamprotula fauna that are considered as early Middle Holocene On the basis of 14C dating（6 400±135 a BP ）of shell and characteristic of pottery unearthed，it may be concluded that the manikin culture is considered as Early Yangshao Culture（7 000～6 000 a BP）This fauna is similarto the living Lamprotula fauna from the Dongting Lake，Poyang Lake and Tai Lake and their surrounding waters are in  their assemblage characteristics, and they all belong to the East Ocean Kingdom and ChinaIndia Subkingdom, whichis situated in the subtropic zone

The fossil plants studied  in  this  paper  were  collected  from the Upper  Carboniferous and Permian in  Liujiang Basin, Hebei  Province. This  flora was composed of 86 species in 44 genera  belonging to Filicopsida (41.8%), Cycadopsida  (4.6%), Cordaitopsida  (2.3%), Ginkgopsida (2.3%)  and  Coniferae  2.3%.x Many fossil plants had  the characteristics of Cathaysia flora.  The  flora could be divided into six assemblages in ascending order:Linoptleris neuropleroides-Lepidodiendron galeatum, Neuropteris plicata-Lepidodendron posthumii, Lobatannularia sinensis-Annularia stellata, Pecopteris anderssonii-Pterophyllum daihoense, Cladophlebis permica-Psygmophyllum multipartitumand Uilmannia bronnii-Walchia bipinnata assemblages. According to the sedimentary characteristics and plant assemblages, the evolution  of the flora  could be divided into six stages. In the first stage(Benxi Formation) deep subtidal，lagoon,delta and river occurred allernativelyIn the second stage (Taiyuan  Formation), subtidal，tidal flat and delta occurred alternativelyIn the third stage (Shanxi Formation), swamp, distributary channel, natural levee,and crevasse splay occurred alternatively. In the fourth stage (Lower Shihezi Formation), swamp, distributary channel, and sand bar occurred alternatively. In the fifth satge(Upper Shihezi Formation), large lake lake, natural levee,and river mouth bar changed to point bars and central bars. In the sixth stage(Shiqianfeng Formation), large lake delta, natural levee, river mouth bar and point bar ocurred alternatively.Key wordsLiujiang Basin, Carboniferous,Permian, Cathaysia flora, evolution  of paleaogeographyAbout the authorYang Tongsheng，born in  1958，graduated  from China  University of Geosciences(Beijing) and  obtained Ph. D. degree in 1999.Now he is an  associate  professor,and   is  engaged in paleobotany，sedimentary  environments  and  paleoecology.

On the basis of the previous studies and data from over 20 outcrops,over 150 wells and 12 000 km seismic profiles,especially new drilling data,the lithofacies palaeogeography of the Jurassic in the Qaidam Basin was restudied. Based on the lithofacies palaeogeography maps compiled,the distribution characteristics of Jurassic strata and sedimentary facies was pointed out,the position of hydrocarbongenerating sags and sandstone reservoirs was determined,and the  hydrocarbon potential of the Jurassic was predicted. It was concluded that early and middle Jurassic humid and warm climate was favourable to the deposition of source rocks,and that supply of clastic material from several uplifts was advantageous to forming the sandstone reservoirs. Six types of the sandbodies,i.e. braided stream delta sandbody,shore lake sheet sandbody,shore and shallow lake beach and bar sandbody,fluvial channel sandbody,turbidity fan sandbody and nearshore submerged fan sandbody,and 30 advantageous sandbodies were determined. The source rocks deposited in a lot of semideep and deep lakes supplied abundant hydrocarbons,and the 8 source sags of different sizes totally over 4 000 km2 in area were located. The evolution of the palaeogeography shows that many types of sourcereservoircap rock assemblages were developed in this area. It was pointed out that the Lenghu,Kunteyiand MahaigaxiuYuka areas are favorable for hydrocarbon exploration in the future.

Taking the Faulted Block Guan 104,Wangguantun Oilfield,Huanghua Depression,Bohai Bay Basin as an example,this paper deals with flow units study of braided river reservoir. The step of research includes two foldsThe first is the analysis of seepage barrier and connected sandbody,and then the analysis of seepage variation. The main microfacies are midchannel bar,braided channel and overbank. The types of seepage barriers include shale and cemented belts. Through seepage variation analysis, four kinds of flow units were classified in the braided river reservoir of ZaoⅠ and ZaoⅡ oilcontaining interval Faulted Block Guan104. Flow unit I is characterized by mediumhigh porosity and permeability reservoir,mainly distributed in midchannel bar and the core of braided channels. Flow unit II is characterized by medium porosity and medium to low permeability reservoir,mainly distributed in braided channels. Flow unit III is characterized by medium to low porosity and low permeability reservoir,mainly distributed in the margin of channels and overbank. Flow unit IV is in fact nonreservoir with extremely low permeability. Lastly the distribution model of flow units of the studying area was made through the analysis of seepage barrier and seepage variation. The study is very important to optimize the oilfield development adjustment plan.

The paleolandform of the pre Jurassic was reconstructed by the method of mold. The research shows that the paleomorphic units in the study area includes three slopes,three river valleys,two mounds and one ridge,i.e.,the East Jiyuan slope,Dingbian slope and Jingbian slope ; the Ganshaan river valley, Ningshan river valley and Mengshan river valley;the Wuqi mound and Jinding mound; and the Xinanbian ridge. The early deposition of Yanan Formation is controlled by the prejurassic paleolandform. In the period of Yan 10 deposition,the facies mainly belong to fluvial deposition,and the microfacies are mostly primary channel,distributary channels,overbank deposit and overbank swamps. In the period of Yan 9 deposition,the sedimentary environment is deltalacustrine,the subfacies are mostly delta plain and delta front, and the microfacies are distributary channels,interchannel depressions,underwater channels and interchannel bays. The shapes of reservoir sandbodies and distribution patterns are bound to change with  the different sedimentary environments in the same paleolandform units,and make great influence on the formation and distribution of the oil reservoirs. The formation of paleolandform oil reservoirs is mostly restricted by the source of the oil and traps. The paleogeomorphic sedimentary combination and migration channels also the are major conditions of forming different types of paleogeomorphic reservoirs. Three paleogeomorphic reservoir models ie. the slopedelta plain combination,mounddelta front combination and combination of slopedelta front.have been generalized in DingbianWuqi area on the basis of the  distribution of the oilfields,the paleolandforms,the deposition environment of overlying formation, sandbody distribution,migration channels