Source Rock Analysis And Evaluation In The Eastern Part Of Tarim Basin

In this paper, we researched on current relatively weak analysis of the source rock in theeastern part of Tarim basin.We worked out a serious of rock and organic geochemicalanalysis, logging features and other aspects.Based on the previous analysis, reviewedfour old wells’ datas and reports, systematically analysis the organic abundance, types,evolutions, biomarkers and the logging features, in order to got a preliminaryunderstanding of the evolution of the source rocks in the study area.By the studying of the samples’ TOC, Chloroform Bitumen ’A’, S1and S2values, itproved that east hydrocarbon source rocks in the study area develop better and withmore hydrocarbon potential. Meanwhile, we proved that the previous so-calledhigh-level segment of the abundance of organic matter illusion is simply caused by thecontamination of organic mud. Using kerogen carbon isotope element methodcombined with organic matter saturated hydrocarbon values, indicating the hydrocarbonsource rocks in this area came from multiphase endogenous sources. Samples vitrinitereflectance values, which was positively correlated with the depth, fall in Mature–OverMature area, with increasing depth, the degree of evolution is increased.We analysis the source rocks’ chloroform bitumen "A" family components, organiccarbon isotopes and saturated hydrocarbon chromatography, proved that the parentmaterial mainly come from the higher plants, and also mixed with the lower plants likealgae, indicates the mixed facies,which from both continental and marine, the reversephenomenon of bitumen "A" family components is controlled by the sedimentaryenvironment (normal seawater) changes impaction. Sterane and Terpane analysis showna consistent result the same as the higher degree of evolution which reflected from Rovalues.We established the logging mathematical model through logging Acoustic time andlogging Resistivity, and use the model to calculate the source rocks. Results shown well fitness relationship betweent the actual values and the caculated values. This kindof correspoondence provide us an evidence of the source rock distribution in thelongitudinal direction in the easthern of Tarim basin.