CAJ | 학술논문

四川盆地西北部下侏罗统白田坝组砂砾岩型储层分布面积广，为盆内碎屑岩气藏的扩大勘探展示了全新领域。通过野外剖面观察、地层及砂砾岩追踪对比、典型相序精细描述等方法，首次对地质背景、物源展布规律、沉积体系及演化模式进行了系统研究。研究表明中三叠世末的印支运动奠定了四川盆地西北部下侏罗统沉积早期“西陡北缓”的古构造格局的基础，东北侧米仓山前缘为向盆内形变强度逐减的紧密阶梯状冲断褶皱带，有利于沉积物长距离搬运，为盆内的主要物源。西北侧龙门山表现为挤压造山运动，地势较陡，季节性山区河流在山前形成大小不等的冲积扇体，为次要物源。山前-盆内依次发育为冲积扇-扇三角洲-湖泊沉积体系。
사천분지서북부하주라통백전패조사력암형저층분포면적엄，위분내쇄설암기장적확대감탐전시료전신영역。통과야외부면관찰、지층급사력암추종대비、전형상서정세묘술등방법，수차대지질배경、물원전포규률、침적체계급연화모식진행료계통연구。연구표명중삼첩세말적인지운동전정료사천분지서북부하주라통침적조기“서두북완”적고구조격국적기출，동북측미창산전연위향분내형변강도축감적긴밀계제상충단습추대，유리우침적물장거리반운，위분내적주요물원。서북측룡문산표현위제압조산운동，지세교두，계절성산구하류재산전형성대소불등적충적선체，위차요물원。산전-분내의차발육위충적선-선삼각주-호박침적체계。
Glutenite reservoirs are widespread in the Baitianba Formation of the Lower Jurassic in the northwest-ern Sichuan Basin, showing a new field for expanding exploration of intrabasinal clastic rock gas pools. Based on detailed field profile observation, tracking contrast of strata and glutenite, and fine description of typical phase sequence, systematic studies of geologic background, source distribution, depositional system and evolution mode have been carried out. During the late Triassic, the Indosinian Movement laid the palaeostructure pattern of “steep west and gentle north” in early deposits of the Lower Jurassic in the northwestern Sichuan Basin. In the front of the Micang Mountain in the northeast, there was a closed stair-step thrust fold belt and the deformation intensity decreased progressively to the basin, which was favorable for the long distance transportation of deposits and served as the main sources. In the Longmen Mountain in the northwest, compressive orogenic activities took place, leading to steep terrain. Different sizes of alluvial fans formed from seasonal mountain stream before mountain, serving as the secondary sources. From mountain front to basin center, a depositional system from alluvial fan, fan delta to lacustrine developed.