Aer sag is a new one that has been discovered fast by the use of new data in Erlian Basin in recent years, and it will become an important replacement area for increasing reserves and production. This paper summarizes in details the exploration history in the sag that consists of three stages, i.e. discovery of target area, breakthrough in deployment optimization, and integer control of scales, and makes an abstract of preliminary study, deployment of decision-making, production implementation and other methods to accelerate exploration,which may be good reference to the exploration of new areas and new sags.

Based on analyzing the petroleum characteristics of Southwestern Qaidam Basin, in view of the existing problems in current exploration, suggestions are proposed for further exploration and study. First, seismic exploration should be launched on the piedmont overthrust nappe in the Kunlun Mountains located in Southwestern Qaidam Basin, learning the original basin boundary, finding out the distribution range, structural attitude, high focus location of downdip sedimentary rock of complex overthrust belt, and finding new exploration domains. Second, with regard to the old oilfields and oil and gas structures that have been discovered in Qigequan-Dongchaishan oil and gas accumulation zone, 3D seismic data should be fully used for variable velocity mapping, ascertaining structural attitude and lateral reservoir prediction, studying new hydrocarbon reservoir assemblages probably exist in deep and shallow layers, enhancing oil recovery increasingly, ensuring high and stable yields of old oilfields, launching sequence stratigraphy study with great efforts, identifying the superimposed relation between hydrocarbon center and favorable reservoir facies and the distribution of hydrocarbon source rock, finding out the stratigraphic pinch-out zone and lithologically changing zone, ascertaining lithostratigrapic traps, and finding new hydrocarbon strata and area. Third, fine structural interpretation should be carried out: studying the effect of genetic potential of downdip of several large overthrust belts and its associated structure on oil and gas accumulation; studying the probable existence of small fault blocks and low-amplitude structure in the periphery of old oilfields, ascertaining the local strucure, lithologic traps, stratigraphic traps, and buried-hill traps that have been discovered in the great Kunbei fault.

To find out the genesis and distribution of volcanic reservoir in Kalagang Formation of Upper Carboniferous System of Malang sag in Santanghu Basin, from the analysis of the geologic characteristics of volcanic reservoir and the controlling factors of reservoir formation, it is pointed out that the key controlling factors of reservoir formation are volcanic facies, high-quality hydrocarbon source rock, fracture and unconformity. Highquality hydrocarbon source rock of Haerjiawu Formation of Upper Carboniferous System provides rich oil source for the volcanic reservoir of Kalagang Formation, unconformity and widely-developed fractures do not only provide conditions for the formation of volcanic reservoir, but they are the channel of upward migration of lower oil and gas. Further oil and gas exploration should be carried out in the volcanic rock weathering crust development area near aquifer region between the nip-out lines of Permian Tiaohu Formation and Upper Carboniferous Kalagang Formation. The southeast edge of Niudong area, Mabei structural zone, and Madong structural zone are favorable for oil and gas exploration

Dawangzhuang area in Raoyang sag is abundant in oil and gas resources and it has favorable structural setting. Sandbody developed in the meandering river channel of Dongying Formation, and reservoir features in medium porosity and medium permeability. The first member of Dongying Formation is a regional cap rock, fault is a major channel for vertical oil and gas migration, oil and gas is migrated terracedly and in the shape of "T" or reticulately. The area has favorable conditions for the formation of "lower-generating-upper reservoiring" type sandstone lithologic reservoir. It has favorable conditions for hydrocarbon preservation, after oil and gas are accumulated at Neogene Minghuazhen period, because structural movement gets weakened and fault is not developed. Two typical reservoir-forming patterns exist in the area: one is the pattern of channel sandstone lithologic and updip pinchout reservoir in the negative area of downthrow block of contemporaneous fault; the other is the channel sandstone lithologic and lateral pinchout reservoir in the flank of Dawangzhuang structure. The formation and distribution of channel sandstone reservoir of Dongying Formation is mainly controlled by oil and gas resources, structures and lithology. Oil reservoir is mainly lithologic and structural-lithologic.

Lower Ordovician weathered crust palaeokarst was formed in Tazhong area due to the middle Caledonian orogeny in Tarim Basin. The palaeokarst was developed in middle Caledonian, and it features in less intensity of corrosion, poor reservoir quality and wide distribution. Vertically, it is distributed by zones, while horizontally in layers. The controlling factors of palaeokarstification in middle Caledonian mainly include palaeogeomorphology, palaeoclimate, sedimentary facies, stratigraphic sequence, and fossil fracture. The prospect areas have been predicted by above mentioned controlling factors.

According to a large number of data about core observation, thin section analysis and reservoir properties, systematic study is conducted on diagenesis type and diagenetic sequence, pore types and diagenetic pore evolution, major controlling factors of reservoir properties of Fuyu oil beds in Zhaoyuan-Taipingchuan Area of Songliao Basin. It is indicated that silicate dissolved pore developed well in sandstone reservoir in Sanzhao sag. Secondary pore belt is also found, of which the contribution rate to porosity may reach 10%. This leads to the development of two types of sandstone reservoir: one is the residual primary intergranular pore reservoir which is distributed in Changchunling anticline belt, Chaoyanggou sidestep, Taipingchuan and Shangjia structures; the other is a mixture of residual primary intergranular porosity and secondary dissolved porosity which is distributed in Sanzhao sag. The lower limit of effective reservoir is raised by the development of secondary dissolved pore

Jinzhou 25-1 Oilfield is a large-scale light oil & gas field discovered recently in Bohai Sea Area. So far it is the largest one in the area, and it also is the first hundred-million-ton oilfield in Liaoxi Sag. The main interval of interest in the oilfield is Shahejie Formation in Paleogene. This oilfield is composed of a lot of complex fault-blocks with perfectly reservoir-gap combination. Jingzhou25-1 oilfield is a large scale self-contained oilfield with the characteristics of shallow burying, large reserves, high petroleum abundance, low density and high deliverability. The discovery of this oilfield will not only enlarge the reserves, but also bring a lot of enlightenment of hydrocarbon prospecting to Liaodong Bay which may be more important than the discovery itself.

Because of the special seismic geologic condition, the original 3D seismic data in Nanpu beach area could not effectively meet its technical needs of petroleum production. Since 2002, on the basis of rich oil sag congregation rules and the integer geologic evaluation, the integer high resolution 3D seismic acquisition system was designed. Based on scientific design and strict construction, advanced acquisition technologies and existing equipment are applied sufficiently, such as flexi-bin geometry, PATCH bind geometry, OBC submarine cable, solving the existing problems of 3D seismic data acquisition in beach area preferably, obtaining high-quality seismic data, and providing a basis for the exploration in Nanpu beach area.

The pyrolith reservoir of Saihantala sag in Erlian Basin is an important exploration area and has been given high priority in recent years. Jurassic andesite and basalt of the area are the main drilling target. It is one of the exploration difficulties to predict the distribution of pyrolith reservoir effectively. Aiming at the lava reservoir characteristics and difficulties in prediction, some methods are used to predict the spatial distribution patterns and the thickness changes of andesite and basalt, such as nature gamma analog acoustic wave inversion, nature gamma reservoir parameter inversion, and seismic attributes. According to the primal physiognomy of lava, characteristics of the fracture structure, seismic facies, the cause formation method and attributes predicting method are used to predict the characteristics of volcanic rock. The volcanic facies is predicted by synthesizing the volcanic lithology and the result of inversion prediction, in combination with core data. The development areas of fracture and volcano slopes which are at a middle distance from the volcano center are considered to be favorable reservoirs.

Low-amplitude oil and gas structure is a difficulty in identifying traps in seismic exploration, while reservoir seismic prediction is the core of subtle trap identification. Using the up-to-date seismic technology, through the long-term prediction of reservoir lithology, morphology, physical property, and oil-bearing property of the Oriente Basin in Ecuador in the northwest of South America, systematic seismic interpretation technologies which are based on high-precision geophysical data and suitable for low-amplitude structural trap identification are developed

As the first exploration well in the deep water area of eastern South China Sea, Well LW3-1-1 is located in eastern Baiyun sag, Pearl River Mouth basin. The four industrial gas flow zones (Gas1-Gas4) are discovered in Zhujiang and Zhuhai Formations in this well. The fluorescence color, homogeneous temperature, hydrocarbon inclusion abundance and diagenesis order of fluid inclusions in the four gas zones are conducted. In combination with bury history and thermal evaluation history, the results show that the two periods of oil and one period of gas charging occurred in Zhujiang and Zhuhai Formations in this well. The hydrocarbons mainly derived from Enping and Zhuhai source rocks. The hydrocarbon charging time of Gas1-Gas3 zones and Gas4 zone is respectively about 8-0Ma and 5-0Ma, with relatively intensive oil charging in Gas1 and Gas2 zones.

By analyzing the cost of prospecting well in 12 main prospect areas in the three big basins in the west, the structure, influential factors, and control of the cost of marine oil and gas prospecting well are analyzed systematically. First, a basic cost model that is composed of seven types of cost (34 items) such as drilling cost, well-log cost, logging, and oil production testing cost is presented in this paper. Secondly, according to the exploration practice in the three big basins in the past few years, quantitative analysis is carried out on the effect of five major controlling factors (nine items) including geology, price, market and affiliate transaction, engineering management, and policies on the cost of prospecting well. Thirdly, a sensitivity model is applied to select the key factors that affect the cost in 12 main prospect areas. Five conclusions are made as well. For example, well test is concluded as the main factor affecting the cost of prospecting well in mid-shallow and rigid sandstone reservoir featuring in low permeability, well depth and well test are the key factors that result in the higher cost of prospecting well in deep clastic rock and volcanic rock reservoir. Finally, methods and suggestions for controlling the cost, i.e. optimize casing structure and reduce the cost of related materials such as pipes, strengthen drilling project management, reduce accident rate, and shorten drilling cycle

Based on SINOPEC's pilot project -Study on Exploration Well Deployment Decision Support System-, according to the comprehensive requirement of exploration well deployment work of the petroleum industry for exploration information, a set of exploration well deployment decision support solutions are proposed. By fully using exploration database and information technology, a comprehensive exploration information application platform that integrates g data management, data inquiry, and visual display is built to provide researchers with useful data, enable the management department to master the project flow without delay, offer decision makers accurate and reliable basis to make decisions with great convenience, low risk and high efficiency. On the basis of the application of database technology to exploration well deployment decision in oilfield, it gets feasible to transform traditional work flow and patterns in exploration domains of petroleum industry and promote the overall level of exploration with high efficiency. It has a definite value as reference to domestic oil exploration industry

Zhaisai, Alakeer, Yili, and Baerkashi Basins in Southeast Kazakhstan all belong to the Kazakhstan Basin System. They are adjacent to Xinjiang Uygur Autonomous Region and have a low level of oil and gas exploration, among which the main sedimentary bodies of Zhaisang and Yili Basins are located in the boundary of Kazakhstan. Through the analysis, study and comparison of petroleum geologic conditions, these basins are considered to be similar to the Junggar Basin, in particular, Zhaisang Basin shows evidences of oil and gas in Carboniferous System and commercial oil and gas flow in Permian and Triassic Systems, Alakeer Basin has a great potential in exploration, and Yilin Basin has favorable hydrocarbon potential. These perceptions are of great significance to the development of transnational oil and gas exploration and development strategies and the Upper Paleozoic oil and gas exploration in northern Xinjiang. Meanwhile, oil and gas environment, policies, laws and regulations in Kazakhstan are studied in details. It is proposed that geopolitical advantages and strong technical force in Xinjiang be an important support for the oil and gas strategy of CNPC in Central Asia.

Jizhong Depression of Bohai Sea Basin in Huabei Oilfield is a close neighbour of Ordos Basin. After more than 30 years of exploration, favorable evidences of oil and gas are shown in Neopaleozoic Carboniferous-Permian of the Depression, and commercial oil and gas flow is obtained. From the analysis of available data, the geologic characteristics of the Basin such as source bed, reservoir, source-reservoir-cap rock assemblage, evidences of oil and gas are as good as the basic geologic conditions of Ordos Basin. In recent years, oil and gas reserves and production have been increased considerably in Changqing Oilfield, so it is feasible to select Neopaleozoic Carboniferous-Permian of Jizhong Depression as one of the areas favorable for further exploration in Huabei Oilfield, and the major target for making breakthroughs in exploring new domains and new strata and increasing reserves and production