川中-川南过渡带雷口坡组沉积相特征

Sedimentary Facies of the Triassic Leikoupo Formation in the Central-South Sichuan Intermediate Zone

根据四川盆地中三叠统雷口坡组的区域背景资料,对川中—川南过渡带雷口坡组的沉积特征进行研究,认为雷口坡组属于陆表海型局限～蒸发海台地相沉积,可进一步划分为粒屑滩、半局限泻湖、局限泻湖、蒸发泻湖等4种亚相及10余种微相,其中,雷一1亚段的颗粒滩亚相是本区雷口坡组主要的有利储集相带。通过对重点层段雷口坡组雷一1亚段的沉积微相平面展布特征分析,建立了该亚段颗粒云岩沉积期的陆表海碳酸盐岩台地相的沉积演化模式,并认识到本区雷口坡组沉积相受古气候、相对海平面变化、构造活动以及继承性古隆起的影响,在纵向上具有继承性,平面上分布稳定。

The study indicates that the Middle Triassic Leikoupo Formation in the central-south Sichuan intermediate zone belongs to restricted platform and evaporate platform facies which may be divided into 4 subfacies such as grain dust beach,semirestricted lagoon,restricted lagoon and evaporate lagoon and more than 10 microfacies.Study of the first submember of the first Member of the Leikoupo Formation indicates that paleoclimate,eustacy,tectonism and old uplift had an effect on sedimentation of the Leikoupo Formation.