Turpan-hami Basin, South Pratyeka Luo Tage Carboniferous Sedimentary Facies And Its Control On Hydrocarbon Source Rocks

Turpan Basin,as the important petroliferous sedimentary basin in the west of China,is one of the most potential basins prospecting for marine oil-gas fields. The results show that some gas and oil in the reservoir come from the carboniferous, so the fundamental rearch on the types of sedimentary facies, the character of plane distribution and the evaluation of source rock is selected for little work on it for the small amount of oil wells drilling in deep burial carboniferous, the result of which provided guiding significance for the carboniferous prospecting in Turpan Basin.Under the guidance of basic principles, methods of sedimentology, petroleum geology and organic geochemistry, this thesis takes the carboniferous from Jueluotage area in the south margin of Turpan Basin as the main object of study, By using the research thinking from point to line and line to area, basis geological work like the stratigraphic division and correlation, analysis and distribution of sedimentary facies and evaluation of source rock was mainly carried out on the basis of collecting and arranging the previous research results.The investigation and measure of four outcrops in Dikaner, Xida Ditch in Yamansu, Dongda Ditch in Yamansu, Mountain Little Huang showed that, the studied area was mainly littoral neritic facies in Xiaorequanzi stage of early carboniferous, which was characterized by intermediate-felsic volcanic rocks and volcaniclasic rocks; the west of the studied area was mainly the delta-littoral neritic facies and the east area was the shelf-deep sea facies in Yamansu stage of early carboniferous, the main lithology was terrigenous fine grained clastic, biolithite, limestone and marl; the west area was mainly the delta facies and the east was shelf-deep sea facies; the main lithology was tuffaceous sands, gritstone of delat facies and tuffaceous siltstone, mudstone and cherts of shelf-deep sea facies.On the basis of detailedly discribing the types and feature of sedimentary facies(sub facies, micro facies), meanwhile combining the data of other sections and points, sedimentary facies lateral correlation was made, distribution and evolution law was established and facies models were set up including the delat-estuarine-littoral neritic facies and littoral neritic-platform-shelf-slope-deep sea facies.The dark mudstone mainly developed in the Dikaner Formation of the upper carboniferous and marl mainly developed in the Yamansu Formation of the lower carboniferous consist of the potential source rock in the research area. Though the primary evaluation of the source rock of the outcrop and underground core, the medium organic matter abundance, humic type, low maturity can be concluded; though the discussion of the correlation of the sedimentary facies and the source rock, the most favorable environment of the source rock was the shelf-deep sea basin and the carbonate platform.