CAJ | 학술논문

四川盆地新场地区须四段储集砂岩在整体致密背景下发育较多的相对优质储层。作者使用显微镜观察、阴极发光分析及扫描电镜分析等手段，研究须四段相对优质储层特征，结果表明，相对优质储层一般发育在分选性中等-好的中粒砂岩中，塑性的沉积岩碎屑相对较少，胶结物尤其是碳酸盐胶结物含量相对较低，而硅质胶结物和自生高岭石含量则相对较高；储层的孔隙类型以长石溶蚀孔为主，原生粒间孔相对较少。在相对优质储层特征研究的基础上，通过储层初始孔隙度、压实作用损失孔隙度、溶蚀作用增加孔隙度以及胶结作用损失孔隙度的系统研究，恢复了须四段相对优质储层孔隙演化过程。结果显示，压实作用造成的须四段储层孔隙损失率在70％以上，是储层物性变差的第一重要因素；溶蚀作用对须四段储层孔隙的贡献值在3．49％左右；胶结作用损失的孔隙度在6．28％左右。在3种作用的共同影响下，须四段相对优质储层大致在蓬莱镇组沉积中期进入致密化阶段，现今孔隙度在8．9％左右。
사천분지신장지구수사단저집사암재정체치밀배경하발육교다적상대우질저층。작자사용현미경관찰、음겁발광분석급소묘전경분석등수단，연구수사단상대우질저층특정，결과표명，상대우질저층일반발육재분선성중등-호적중립사암중，소성적침적암쇄설상대교소，효결물우기시탄산염효결물함량상대교저，이규질효결물화자생고령석함량칙상대교고；저층적공극류형이장석용식공위주，원생립간공상대교소。재상대우질저층특정연구적기출상，통과저층초시공극도、압실작용손실공극도、용식작용증가공극도이급효결작용손실공극도적계통연구，회복료수사단상대우질저층공극연화과정。결과현시，압실작용조성적수사단저층공극손실솔재70％이상，시저층물성변차적제일중요인소；용식작용대수사단저층공극적공헌치재3．49％좌우；효결작용손실적공극도재6．28％좌우。재3충작용적공동영향하，수사단상대우질저층대치재봉래진조침적중기진입치밀화계단，현금공극도재8．9％좌우。
The sandstone reservoir in T3 x4 (Member 4 of Upper Triassic Xujiahe Formation)of the Xinchang area is the important gas reservoir in the West Sichuan tight sandstone gas region.The relatively high-quality reservoir which more develops under the overall dense background is the important feature of this set of the sandstone.The research shows that the relatively high-quality reservoir generally appears in the medium-grained sandstone whose sorting is medium-good,it has less plastic sedimentary debris,its total content of cements,especially the carbonate cements are relatively low,but its siliceous cement content and authigenic kaolinite content are relatively high.The reservoir pore type is mainly the feldspar dissolution pore,and the primary intergranular pore is relatively less.Based on the research of the characteristics of the relatively high-quality reservoir,and by systematically researching the initial porosity of the reservoir,the compaction making the porosity loss,the dissolution increasing porosity and the cementation causing porosity loss,the authors recovered the porosity evolution process of the relatively high-quality reservoir in T3 x4 .The research shows that the compaction causes the T3 x4 reservoir pore loss rate reach 70% or more,and is the first important factor that makes reservoir properties get poor,the dissolution makes the contribution of around 3.49% to the T3 x4 reservoir pore and the cementation causes the T3 x4 reservoir pore loss rate to be around 6.28%.Under the common effect of the three kinds of action,the relatively high-quality reservoir of T3 x4 roughly entered the densification stage in the middle deposition of Penglaizhen Formation.The current porosity is about 8.9%.