鲁西寒武系—下奥陶统层序地层研究新进展

NEW ADVANCES IN THE STUDY OF THE CAMBRIAN TO LOWER ORDOVICIAN SEQUENCE-STRATIGRAPHY IN THE WEST SHANDONG

鲁西寒武系—下奥陶统层序地层可划分为2个二级层序、12个三级层序,二级层序界面在馒头组下页岩段与馒头组上页岩段之间或馒头组洪河段与张夏组下灰岩段之间,该界面在鲁西地区普遍存在,延伸稳定,自西北向东南由假整合向似整合过渡,界面类型属型不整合。

Based on the sequence-stratigraphic data from the regional geologic survey, a study of the Cambrian to Early Ordovician sequence-stratigraphy of the West Shandong has been made,and these strata may be divided into 2 second-order and 12 third-order sequences. A second-order sequence interface has been found between the Upper and Lower Shale Members of the Mantou Formation or between the Honghe Member of the Mantou Formation and the Lower Limestone Member of the Changhia Formation. This interface is common in the West Shandong area and has a stable extension, transitional from pseudoconformity to parapseudoconformity in the northwest-southeast direction. Interface belongs to Type Ⅱ disconformity.