川东沙罐坪石炭系沉积微相特征及其储渗单元

SEDIMENTARY MICROFACIES FEATURE AND THE RESERVOIR PERMEABILITY UNITS IN CARBONIFEROUS,SHAGUANPING,EASTERN SICHUAN

石炭系气藏是川东地区沙罐坪气田的主力气藏,属裂缝-孔隙型气藏,随着勘探开发的深入,系统研究黄龙组沉积体系的内部构成、空间配置与沉积相模式,理清储集体的分布规律,对划分气藏的储渗单元显得十分迫切。在充分利用地质、测井、薄片等资料的基础上,采用沉积体系分析方法,对黄龙组的岩相组合和沉积环境做了详细研究,识别出3种亚相、8种微相,研究了各亚相的沉积特征和沉积条件。对石炭系气藏进行中-高渗区、低渗区的储渗单元划分,储渗单元在含气范围内呈"主体高外围低"的整体分布态势,单元划分为气田中后期开发调整方案的制定提供了科学依据。

The Carboniferous gas reservoir is the key one in Shaguanping gas field,eastern Sichuan,it belongs to fracture-pore-typed gas reservoir.It is critically important to divide reservoir units that study systematically the internal texture,spatial allocation and sedimentary facies model of Huanglong Formation and identify the distribution law of the units.Based on the data of geology,well logging and thin sections,by using sedimentary system analysis,lithologic facies association and sedimentary environment of Huanglong Formation are studied in detail,three sub-facies and eight micro-facies are figured out,all the sedimentary features and conditions of the sub-facies are researched.The reservoir permeability units in Carboniferous gas reservoirs are grouped into high-medium permeable zones and low permeable zone,in general,the units appear 'high permeability internally and low permeability marginally'.The division provides scientific reference for middle-late period development.