Study Of Characterizations Of Favourable Carboniferous Volcanics Reservoir In Shixi Oilfield

In recent years, with the increasing demands of oil and gas in the nations of the world and more difficulties of oil and gas exploration than before, looking for new reservoirs and reservoir types has become more and more important in the research fields. At the present time, volcanic hydrocarbon reservoir already become a light in oil and gas exploration in the world.Volcanic reservoirs widely distribute in many countries. We have found many considerable oil and gas pool in them and so did in our country, such as carboniferous volcanic reservoir of SHIXI in Junggar basin.Volcanic reservoir has many characteristics, such as it has many styles and complex ingredients, its pore has long formative stage, many styles and quick evolution, it' s cracks form easily and have many genetic types etc. This article takes the carboniferous volcanic reservoir of SHIXI in Juggar basin as researching object. It researches the factors which affect the formation of pore in volcanic reserviors and researches developed characteristics and regularities of distribution of high porosity, compact layer and crack in differ layers. At last it forecasts avail oil reservoir of carboniferous volcanic in SHIXI.According to these researches, this article has drawn two conclusions: the one is about the formation of pore of volcanic reserviors, and the other is the method to researching and predicting advantageous volcanic reserviors.The aspect about formation of volcanic reserviors porosities:1 The formation of volcanic reserviors is very distinctiveness and this decide that its' lithology is very complex. Its lithology is more complex than sedimentary rocks because volcanic have many differencea in the process of diagenesis and evolutionary.2 The formation and preservation of the pore of volcanic have little relationship to buried depth, without overt linear relationship. Deep-seated igneous rocks can preserve good pores. The porosity of carboniferous volcanic in SHIXI is better than calculate and carbonatite in the same depth, and ithas a little discrepancy, which is compared with lighter volcanics.3 The formation of volcanic reservior' s cracks is avail of forming better reservoir. During the formation and buried process, the cracks which formed in early condensed into rocks process and laate-tectogenesis are in favor of communicating and holding oil and gas.4 Diagenesis had some effects to the developing of pore of carboniferous volcanic reservoir in SHIXI. Corrosion action is the most important factor that affected the porosity of volcanic.5 Different lithology had some effects to the formation of pore of carboniferous volcanic reservoir in SHIXI. Thereinto the porosities are higher than other lithologies in volcaniclastic rock and neutral to neutral acidic volcanic.The aspect about lucrative of volcanic reservoir:Volcanic, which have high porosity, are advantage of storing oil and gas. The cracks in volcanic are good to holding oil and gas too. The volcanic, which has good porosity and cracks, is the most reserviors to holding oil and gas. The volcanic, which has compact layer, can gather oil gas in certain layers.The distribution of carboniferous volcanics in SHIXI oilfield possesses some zonality, and B layer of carboniferous is the best to holding gas or oil.In the view of facies, Volcanics overflowing facies is avail of accumulating gas and oil.In a word, in the east and the middle of research region, which is overflowing facies, is the best area to accumulate oil and gas.