CAJ | 학술논문

鄂尔多斯盆地镇泾区块长8致密砂岩储层普遍发育钙质夹层，本文利用露头、岩芯、薄片及测井等资料，对钙质夹层的岩性特征、电性特征、分布规律以及与天然裂缝分布的关系进行了研究。研究表明，钙质夹层具有明显的低伽马、低声波时差、高密度、高感应的特点，电成像测井表现为明显的亮色条带。钙质夹层主要分布在部分水下分流河道砂体的中部或下部及河口坝砂体的中部或上部，同时也发育在一些分选较好、颗粒支撑的薄层细砂岩中以及砂泥岩的接触地带。钙质夹层内主要发育高角度构造裂缝，不发育近水平成岩裂缝；与非钙质胶结致密砂岩储层相比，钙质夹层脆性较大，天然裂缝更为发育，且大部分裂缝被方解石充填，为无效裂缝；钙质夹层层厚及岩性界面控制着裂缝纵向延伸高度。论文成果对进一步研究致密储层天然裂缝的分布模式，弄清裂缝对注水开发的影响具有重要意义。
악이다사분지진경구괴장8치밀사암저층보편발육개질협층，본문이용로두、암심、박편급측정등자료，대개질협층적암성특정、전성특정、분포규률이급여천연렬봉분포적관계진행료연구。연구표명，개질협층구유명현적저가마、저성파시차、고밀도、고감응적특점，전성상측정표현위명현적량색조대。개질협층주요분포재부분수하분류하도사체적중부혹하부급하구패사체적중부혹상부，동시야발육재일사분선교호、과립지탱적박층세사암중이급사니암적접촉지대。개질협층내주요발육고각도구조렬봉，불발육근수평성암렬봉；여비개질효결치밀사암저층상비，개질협층취성교대，천연렬봉경위발육，차대부분렬봉피방해석충전，위무효렬봉；개질협층층후급암성계면공제착렬봉종향연신고도。논문성과대진일보연구치밀저층천연렬봉적분포모식，롱청렬봉대주수개발적영향구유중요의의。
Calcareous interbeds develop widely in Chang 8 tight sandstone reservoirs,Zhenjing Area,Ordos Basin.This paper reported the lithology,electricity,distributing characteristies of the calcareous interbed and the relationship with the distribution of natural fractures based on outcrops,cores and logs data.Studies have shown that calcareous interbeds have the following electrical characteristics.Natural gamma ray log is low.Longitudinal wave offset and transverse wave offset time are also low.The value of density logging is high and induction logging is obvious high.Electric imaging logging has the characteristic of clear light yellow (light).Good development of calcareous interbeds presents at the middle or bottom of underwater distributary channel sand body and at the top or middle of mouth bar sand body in delta front.Besides,calcareous interbeds are distributed in well-sorted,grain supported fine sandstones and contact zones of mudstones and sandstones.There are mainly high angle tectonic fractures in calcareous interbeds with little nearly horizontal diagenetic fractures.Calcareous interbeds are brittler than non-calcareous cementation tight sandstone.In consequence there are more natural fractures and the majority of them are filled with calcite taken as invalid.The thickness and lithologic interface of calcareous inerbeds determine the longitudinal height of fractures.All the achievements of this thesis are significant to study the distribution patterns of natural fractures and the effect of fractures on water flooding development.