川东地区嘉陵江组四段膏盐岩分布的沉积环境分析

四川盆地东部地区嘉陵江组嘉四段沉积环境是局限海台地蒸发岩相,水体封闭,有利成盐。以川东地区油气勘探的500余口实际钻井资料为基础,通过岩性微相的研究,探讨川东地区的古地貌特征,寻找成盐的微环境因素,有助于从区域上预测盐类的分布。T1j4盐湖主要分布在蒸发岩沉积中心——膏盆相,但位于膏盆相的周缘地带和膏盆内部堤坝周围,少部分分布在膏盆边缘相,区域上则主要分布在宣汉、达州、万县、云阳、垫江及渠县等地区,有一定的继承性。

Sedimentary Environment Analysis on T_1j_4 Gypsum-salt Rock in Eastern Sichuan Basin

Sedimentary environment of T_1j_4 in eastern Sichuan basin was an isolated and closed evaporation platform which being favorable to salt sediment. The paper discusses the distribution of salt mine by lithological microfacies and paleogeomorphology based on the data of more than 500 oil-gas explorations drilling wells in eastern Sichuan basin. It indicates that salt lakes which having geological succession were mainly distributed in the boundary region of the evaporative depocenter( gypsic-basin facies) and the surrounding of interior dyke, located in Xuanhan, Dazhou, Wanxian, Dianjiang and Quxian, while some saltlakes were distributed in the gypsic-basin marginal facies.