Archean Eon (from 4.03 to 2.42Ga) is a major period of crust formation and biosphere establishment，characterized by a highly reducing atmosphere. Substantial amounts of molecular oxygen might have accumulated locally in protected shallow-water environments that favored cyanobacterial productivity and were sufficiently isolated;and this type of protected shallow-water environments results in an “Archean oxygen oases”even though under an anoxic atmosphere. Thus，identification and research of an Archean oxygen oasis become an important clue for the further understanding of the rise of atmospheric oxygen concentration and the origin of oxygenic photosynthesis，which is a hot point of the Precambrian sedimentology. Interestingly and fascinatingly，studies and interpretations on the Archean marine limestones (ca. 2.8Ga), the primary haematite formed in an oxygenated sea (ca. 3.46Ga) and the stromatolite reef (ca. 3.46Ga), become some typically successful examples for the research of the Archean oxygen oases. Tracing these fruitful and starting researches will be propitious to further understanding both the sophisticated evolutionary process of surface environment and its palaeogeographical reconstruction in the early Earth，and are meaningful to broaden the studying domain of sedimentology and palaeogeography.

Based on the analysis of wells,loggings,seismic information and other materials of synthetic study,palaeogeography of different formations or members of the Sinian in Upper Yangtze Region was mapped,sedimentation and reservoirs were systematically studied. It indicated that the Upper Yangtze Platform was a semi-platform during the Sinian,and the process of sedimentation could be divided into three stages of pre-platform deposition,carbonate platform deposition and restricted sea basin deposition. The Chuan-Dian great rift adjoining to the western margin of the Upper Yangtze Platform played an important role in the platform evolution,formation of sedimentary palaeogeography framework and facies distribution of the Upper Yangtze Region. During the period of the Upper Sinian Dengying Formation,the Upper Yangtze Platform had ever undergone a fast subsidence caused by rifting,going through an ephemeral change from platform to basin. The evolution of the lithofacies palaeogeography controlled the formation and distribution of reservoirs of the Sinian in Sichuan Basin,and also controlled the formation and distribution of conventional petroleum and shale gas in this region.

Based on the analysis of outcrops,drilling core samples and thin sections,this paper summarized the sedimentary microfacies and its vertical sequence types of the 4th sub-member of Member 5 of Majiagou Formation in Ordovician of central and eastern Ordos Basin. The palaeogeography of four periods which are M5₄³,M5₄²,M5₄^1b and M5₄^1a of Majiagou Formation is studied,mainly based on the parameters including the cumulative thickness of gypsum-salt rock and its ratio to the whole formation. The result shows that the study area is an arid environment with a low sea level during the 4th sub-member of Member 5 of Majiagou depositional period. The sedimentary pattern was uplifts alternate with depressions. From the early to later,the relative sea-level gradually rose and the salinity reduced,which controlled the development and spatial distribution of sedimentary microfacies of these sub-members.

Triassic Yanchang Formation is one of the main targets of oil and gas exploration in northern Zhenyuan area. The types and distribution of sandbody are controlled by the palaeogeomorphology. Based on cores,well log analyses,and sandy debris flow viewpoints proposed by Shanmugam,the gravity flow deposits can be divided into turbidites,sandy debris flow sediments and slump rocks. After building the high-resolution sequence stratigraphy framework,an optimized backstripping method is used to restore the deposited terrain,and the palaeogeomorphology map of the studied area is drawn by short-term base level unit. The study finds that the north of Zhenyuan situated near the depositional slope break zone,Chang 7₃ was of the maximum transgression,the degree of the slope is 0.45,turbidites and sandy debris flow sediments developed in the deep lake in the northeastern part of the study area. From Chang 7₃ to Chang 7₂ depositional periods,the base level decended,the mouth bar and the slope break zone gradually advanced to the lake,and the angle of the slope break zone began to decrease;from Chang 7₂ to Chang 7₁ depositional periods,the base level began to rise,the slope break and the sandbody gradually retreated to the shore. From Chang 6₃ to Chang 6₁ depositional periods,the base level decended,sediments deposited in the basin,the slope decreased to 0.1°,sandy debris flow sediments and slump rocks developed under the slope break.

Based on 3D seismic data,well data,core observation and laboratory data,the study of sequence stratigraphic division,the sedimentary characteristics and sandbody distribution of the Cretaceous Qingshuihe Formation in Mosuowan area of Junggar Basin especially the bottom sandstone member which is the main hydrocarbon reservoir are carried out. It is concluded that: (1)The Qingshuihe Formation was divided into the highstand system tract,the transgressive system tract and the lowstand system tract. Shallow water braided river delta facies was developed in the lowstand system tract,shallow to semi deep lake facies was developed in the transgressive system tract,and shallow water meandering river delta facies was developed in the highstand system tract. (2)The “bottom sandbody member”consists of 4microfacies types,namely,underwater distributary channel,mouth bar,sheet sand and interdistributary bay,and is located in the shallow water braided river delta front that can be divided into inner part and outer part controlled by the north provenance. (3)The sedimentary microfacies model of shallow water braided river delta in the Qingshuihe Formation was constructed based on the regional sedimentary background,and we concluded that the sedimentary evolution process of the Qingshuihe Formation is a complete sedimentary cycle of lake-level fluctuation.

In order to study the characteristics and controlling factors of the reservoirs in the Lower Cambrian Longwangmiao Formation in eastern Sichuan Basin and its adjacent areas,we analyzed the laboratory data of thin sections,cathode luminescence,scanning electron microscope and physical properties, and log data. The result shows that: (1)The main types of reservoir rocks of the Longwangmiao Formation are grain carbonate rocks,and silty-fine crystalline dolostones following. (2)The main types of reservoir space of the Longwangmiao Formation are intergranular(dissolved)pores,intercrystalline(dissolved)pores,intragranular dissolved pores,followed by structural fractures,dissolution fracture. The reservoirs have low porosity and permeability with average matrix porosity of 4.25％ and permeability of 6.25×10^-3μm²; The reservoirs could be divided into two types: the porous type and the fractured-dissolution-porous type. (3)The formation and distribution of the reservoirs in the Longwangmiao Formation may be influenced by three controlling factors including sedimentation,diagenesis and burial process. Sedimentation provided the geological background for the reservoir development;diagenesis was the key factor influencing the reservoir development;and the burying process,which is one of the reasons why the reservoirs in eastern Sichuan Basin have poor quality comparing with those in central and southeastern Sichuan Basin,affected the formation of the reservoirs eventually. (4)It was concluded that the favorable reservoirs were developed mainly in the banks,and secondly in the tidal flats of the restricted platform, overall, considering the lithology, physical property, thickness and distribution range synthetically.

We analyzed the change of settlement density in Yulin area of Shaanxi Province and Luoyang area of Henan Province around 44 Ka BP. The culture of these two areas were both well developed during the period of Longshan (before 44 Ka BP) and the settlement densities of the two areas were on top of the list in China at that time. The further increase of the settlement density occured in Luoyang area during the period of the Xia and Shang Dynasties (after 44 Ka BP), but the density of population and settlement declined sharply in Yulin area after 44 Ka BP，which obviously reflected the decline of the culture. According to the geographical position differences，the mean annual precipitation in Luoyang area is 200mm higher than Yulin area. The landform of the loess hills is the main human activity place in Yulin area，where the limited water resource of river is not easy to be used. The development of dry farming mainly depends on the rainfall. The rainfall is abundant in Luoyang area and human beings can conveniently use river water resources in basin plain. So the fluctuations of the rainfall cannot influence the development of dry farming. The study of palaeoclimate showed that there was a significant climate event around 44 Ka BP. After this climate event，the mean annual precipitation declined approximately from 650mm to 500mm in Luoyang area. But it was still higher than the minimum precipitation that dryland farming needed. So the human culture could develop much further. The mean annual precipitation declined approximately from 450mm to 350mm in Yulin area，which made the climate change from sub-humid to semi-arid. The climate change made dryland farming cannot develop further. This study proves that the differences of the geographical setting and environmental characteristics between the two areas are the basic factors that affect their respective cultural evolution. The climate event around 44 Ka BP is the direct driving factor that leads to two different results．