辽西地区义县组沉积剖面结构分析与对比

THE STRUCTURAL ANALYSIS AND CORRELATION OF SEDIMENTARY SECTIONS OF YIXIAN FORMATION IN WESTERN LIAONING PROVINCE

辽西金岭寺-羊山盆地与阜新-义县盆地的沉积环境分析与对比,一直存在分歧.对两个盆地义县组典型剖面的沉积剖面结构分析,不仅揭示了两个盆地的沉积相特征,而且为两个盆地沉积相的对比提供依据.四合屯地区的沉积相可以划分为冲积扇-河流相、滨湖相、半深-深湖相;义县地区沉积相可以划分为冲积扇-河流相、河流相、滨浅湖与湖相.相同的沉积相由于具体沉积环境的不同而体现出一般性及特殊性.四合屯地区的尖山沟层及以下的沉积相与义县地区的砖城子层及以下的沉积相可对比.两剖面复成分砾岩杂色沉积、泥裂、石膏层等为该区可能存在的干旱气候提供了依据.

Arguments have long existed in the analysis and correlation of the sedimentary environment between Jinlingsi-Yangshan and Fuxin-Yixian basins in Western Liaoning Province. The structural analysis of sedimentary sections of Yixian formation in the two basins not only reveals the features of sedimentary facies, but also provides evidences for the correlation of the sedimentary facies. The sedimentary facies of Sihetun area may be divided into alluvial-fluvial, shore-lacustrine, semi-deep and deep lacustrine; while those in Yixian area can be classified into alluvial-fluvial, fluvial, shore-lacuatrine and lacustrine facies. Because of the differences in sedimentary environment, the same sedimentary facies display generality and particularity. The sedimentary facies of Jianshangou bed and lower strata in Sihetun area can be correlated with those of Zhuanchengzi bed and lower strata in Yixian area. The occurrence of variegated polymictic conglomerate sediment, mud cracks, gypsum strata and so on can provide evidences for aridity climate in Western Liaoning.