Oil reservoirs have been found in Triassic Yanchang Formation and Jurassic Zhiluo Formation, Yan’an Formation, Fuxian Formation, and one-billion-tonnage Jiyuan Oilfield has been discovered. Multi-stage lake rise and fall occurred. Distributary channels in deltaic plain, subaqueous distributary channels, mouth bars in delta front and sandy dam of shore lakes, and other types of sand body were well developed during the process. Source rocks are thick with strong hydrocarbon generation and expulsion ability, which generates hydrocarbon pressurization and becomes the main driving force of oil migration along the fracture, fracture-sand, fracture-unconformity, fracture-sand -unconformity, and other conduit system. This kind of migration and accumulation forms multi-layer composite accumulation mechanism. Reservoir tightening and hydrocarbon accumulation is synchronous. Jiyuan Oilfi eld features in hydrocarbon generation pressurization, bilateral expulsion, near-source accumulation, multiple conduit, and differential accumulation. Geological theory innovation, exploration technological advances and constant exploration practice favor the discovery of Jiyuan Oilfi eld.

Fault development plays a vital role in all the factors controlling gas accumulation in foreland thrust belt, which determines the migration and accumulation of oil and gas, the formation of trap, and the sealing capacity of caprocks. Therefore, the combinations of faultsource- reservoir-cap, of which fault development is the core, determine the channel capacity of oil and gas, the sealing features and the fullness degree of traps, and ultimately control the accumulation of gas. According to the structure characteristics, the association of sourcereservoir- cap, the main controlling factors of accumulation and the analysis of the known hydrocarbon reservoirs in different regions of the foreland thrust belt in Kuqa Depression, the combinations of fault-source-reservoir-cap were founded and the control of different combinations on gas accumulation was elaborated in this paper. The combination of fault-source-reservoir-cap in Keshen is the most optimal, which is connected with Jurassic gas at the bottom and does not cut through Kumugelemu's gypsum-salt cap on the top. Not only does it act as a good channel of gas accumulation and migration, but also the closure of caprock is not destroyed, resulting in the continuous distribution of gas. In Kelasu region the fault cuts through both Bashenjiqike’s reservoir and gypsum-salt cap. For these reasons, whether the closure of the cap can accumulate gas is the lateral sealing trap. Gas is accumulated above gypsum-salt rocks in Dawanqi, thus the main factors for gas accumulation are channel capacity of faults that cut through gypsum-salt rocks and suprasalt trap effectiveness. Ichicklick’s source and reservoir are in the same region, so the key factors of gas accumulation are the sealing ability of the updip faults which control the trap and the lithology joint relationship of each wall.

Early Paleozoic of Sichuan Basin underwent fi ve crustal movements, that is, Chengjiang movement, Tongwan movement, Yungui movement, Yeli movement, and Caledonian movement, caused by the northward subduction of Indian Plate and the eastward drift of Eurasian Plate. The two Plates collided with Qinghai-Tibet Plate, causing the latter to swift to the east and collapse in weak zone of Longmen mountain area of western Sichuan Basin. As a result, Qinghai-Tibet Plate reversed eastward and covered Yangtze platform plate, and Sichuan Basin was formed in succession. Because of the fi ve crustal movements, the big fault zones in Longmen Mountain got larger and larger in scale, as a result petroleum exploration reservoirs of Lower Paleozoic moved towards the east gradually and the exploration range got smaller. Exploration here proved that the Yaan-Longnvsi palaeohigh, the Luzhou palaeohigh, and the Tianjingshan palaeohigh were formed, which are favorable for petroleum exploration. In particular, the Yaan-Longnvsi palaeohigh is large, carbonate reservoirs here developed in each period, and there are also many local structures. Moreover, the northwest wing was eroded heavily and was leached by meteoric water for a long time. A great number of ancient karst fi ssures and caves emerged in all reservoirs. When they crossed each other vertically and horizontally, a giant fi ssure and cave system would be formed, which is very good for hydrocarbon accumulation and reservoir formation. There are also many local structures in Luzhou palaeohigh and Tianjingshan palaeohigh, and they could be used for Lower Paleozoic carbonate reservoir drilling and exploration.

Four vibroseis acquisition techniques with high effi ciency including the fl ip-fl op sweeping technique, the slip sweeping technique, the distance separated simultaneous sweeping technique, and the independent simultaneous sweeping technique, and their application both at home and abroad were discussed. The current state of China’s conventional onshore vibroseis acquisition was analyzed thoroughly. For current problems and difficulties in domestic onshore seismic acquisition, flip-flop technique, slip technique and other high-efficiency acquisition techniques were analyzed in terms of acquisition effi ciency, acquisition cost, and seismic effect, etc. How to apply high-effi ciency acquisition techniques in onshore regions of different surface and subsurface geologic conditions in China in the future was prospected

Sulige gas fi eld is a typical gas reservoir of low permeability, low yield, low abundance and large lithology trap. The main gas layer is the eighth member of Shihezi Formation and the fi rst member of Shanxi Formation. Based on electric imaging logging data, seven lithofacies were identified in the eighth member of Shihezi Formation and the first member of Shanxi Formation, including cross-bedding mediumcoarse sandstone, cross-bedding medium-coarse sandstone containing gravel, parallel-bedding sandstone, clumpy conglomerate, graded bedding glutenite, massive-bedding sandstone, and micro-fracture sandstone. Fracture in the eighth member of Shihezi Formation and the fi rst member of Shanxi Formation was also identifi ed. In this paper, the relationship between the fracture and the gas production in gas-bearing zone was discussed, and the distribution law of fracture in plane was summed up. It was shown that physical property, lithology, gas content and thickness of reservoir were main factors controlling single well, while fracture was less important. Based on petrographic analysis, paleocurrent and sedimentary facies were analyzed. It was believed that low-sinuosity meander sedimentary facies developed the upper section of the eight member of Shihezi Formation, and braded river sedimentary facies mainly developed in the lower section. This was of certain directive signifi cance to natural gas exploration and development in this area

Mesozoic erosion thickness of Bongor Basin was restored using mudstone acoustic time difference method, vitrinite refl ectance (R o) method, and stratigraphic correlation method. Result showed that the erosion thickness ranged from 1000 to 2000 m, thick in northern and southern slope while thin in central sag. The quick but intense uplift preserved the good reservoir quality of the P Formation sand body in the lower play. The compressive stress during inversion folded the strata and contributed to the formation of a lot of faulted anticlines and noses which were excellent traps for hydrocarbon accumulation. The fault reactivation triggered by inversion promoted the hydrocarbon migration in Bongor Basin.

Oil and gas resources are rich in Zagros Foreland Basin. The research on giant oil and gas fi elds in Zagros Foreland Basin will enrich petroleum geology theory of foreland basins, and can also provide reference basis for oil and gas exploration in foreland basins. Based on the data of discovered 60 giant oil and gas fi elds in Zagros Foreland Basin, this paper applies the concept and analytical method of petroleum system, dissects giant oil and gas fi elds one by one, and probes into the formation and distribution of giant oil and gas fi elds in the basin. The study shows that the source rocks of giant oil and gas fi elds are Lower Silurian Gahkum Formation, Lower Cretaceous Garau Formation, Middle Cretaceous Kazhdumi Formation, Palaeocene and Eocene Pabdeh Formation. The reservoir rocks of giant oil and gas fi elds are limestone of Oligocene and Lower Miocene Asmari Formation, limestone of Middle Cretaceous Albian and Turonian Bangestan Group, limestone of Triassic Dashtak Formation and Kangan Formation, and limestone of Permian Dalan Formation. Giant oil and gas fi elds are controlled by Miocene Gachasaran Formation evaporite rock seal and Upper Cretaceous Gurpi Formation mudstone. They accumulate in folded anticlinal trap. Giant oil and gas fi elds are mainly distributed in Iran, Iraq and Syria. Big discoveries were made from 1960 to 1979. Oil and gas are rich in the layer of Mesozoic and Cenozoic. The lithology of reservoir is mainly carbonate rock which is buried at a depth less than 3km, and the reserves are less than 1×1010bbl. The factors controlling the distribution of giant oil and gas fi elds are the formation and evolution history of basin and the evolution history before basining, the organic type of source rock, the thermal evolution and distribution, the favorable reservoiring conditions, the high-quality region and direct cap rock, and the folded anticlinal traps favorable for hydrocarbon accumulation and the fracturing pathway favorable for vertical hydrocarbon migration that formed in the process of Neocene orogenic activity and folding. These factors control the distribution area and the accumulation layer of oil and gas.

There are plenty of geothermal resources in oil & gas sedimentary basins. In the context of short energy supply and vigorous development of new energy, development of geothermal resources in oil & gas fi elds is being paid more and more attention. Based on the analysis of geothermal resources in oil & gas fi elds, the possible mode of co-production of oil/gas and geothermal resources was discussed in this paper. Considering the existing low-and medium-temperature power generation technology, the feasibility of using low-and mediumtemperature geothermal resources in oil & gas fi elds to power was analyzed. With the characteristics of geopressured geothermal resources, the potential of using geopressured geothermal water fl ooding in heavy oil reservoir to enhance oil recovery was also investigated. It was concluded that sustainable development of oil & gas fi elds and effi cient utilization of new energy could be realized through the “win-win” cooperation between oil/gas production and geothermal exploitation based on existing infrastructure, technology, geothermal experience and reservoir information in oil & gas fi elds.

This paper probed into the formation conditions and the possible accumulation model of permafrost natural gas hydrate in China, based on such hydrate forming key elements as temperature, air source, water source etc. It mainly analyzed petroleum geology and temperature of Qiangtang Basin, Qilian mountainous region and Mohe Basin, and further summarized natural gas hydrate forming conditions in these regions. The tectonic conditions, air source and temperature of Muli region in Qilian Mountain is relatively better as a whole, which is regarded as favorable for exploration and research of permafrost gas hydrate in China at present. Through analyzing gas hydrate source, petroleum geology, tectonic evolution and other characteristics, it showed that natural gas hydrate formation in Muli region is controlled by fault development. Under the action of the fault, lower thermogenic gas re-migrated to gas hydrate stability zone, forming gas hydrate. Besides conventional gas reservoir can also form hydrate reservoir, based on later tectonic uplift to gas hydrate stability zone