一种高分辨率层序地层学研究的新方法——以准噶尔盆地石南油田为例

高分辨率层序地层学研究必须与具体的高分辨率手段相结合.以准噶尔盆地石南油田含油层段的层序(3级层序)和层组(6级层序)界面的识别和对比为例,提出了一种综合应用测井、录井、钻井等资料进行高分辨率层序地层学研究的新方法.通过对古生物群化石组合,黏土矿物,岩性、电性等特征的研究实现层序界面的识别和对比;通过钙质夹层,泥岩电阻率差异,地层倾角模式的研究实现层组界面的识别和对比.研究发现,泥岩电阻率差异反映出泥岩的沉积物源或沉积相带不同,利用泥岩电阻率差异可以确定层组的叠置关系,判断储层连通性;相同的层组单元中的倾角模式具有可对比性,通过邻井倾角模式的对比可以确定层组的空间展布形态.据此,建立了准噶尔盆地石南油田西山窑组含油层段等时地层格架,定性、定量地表征出该等时地层格架内层组的发育顺序、叠置关系、空间展布形态、以及彼此之间的连通性.

A new approach to studying high-resolution sequence stratigraphy——taking Shinan Oilfield of Junggar Basin as an example

The study of high-resolution sequence stratigraphy must be combined with high-resolution technology.Taking the identification and contrast of sequences and bed sets of Shinan Oilfield in Junggar Basin as an example,a new method is put forward for the study on high-resolution sequence stratigraphy by comprehensively using logging data,drilling data,etc.The identification and contrast of the interfaces between the sequences are finished through the research of characteristics of palaeo-biota fossil combination,clay mineral,reservoir lithology and electricity,and the identification and contrast of the interfaces between the bed sets are finished through the research of calcareous interlayers,difference of shale resistance and pattern of deformation dip.The results shows:the difference of shale resistance reflects the difference of the material sources or facies belts of the shale sediments,the stack relationships between the bet sets and the connectivity among them can be determined by means of the difference of shale resistance;the special distribution of the bed sets can be determined through the comparison of the dip models of adjacent wells.On the basis of the research results,the high-resolution chrostratigraphic framework of the oil-bearing interval of Xishayao member of the oilfield is established,the development order,stack mode,special distibution and connectivity of the bed sets are qualitatively and quantitatively characterized.