勉略宁地区系指陕西汉中西部的勉县、略阳、宁强三县相交地区,西与甘肃、四川毗邻,通常称勉略宁“三角”地带。该区地质构造复杂,震旦亚界目前除未发现青白口系外,其它各系的层序、岩性与我国南、北方震旦亚界的震旦系、蓟县系、长城系基本可以对比。作为震旦亚界的碧口群分布尤广(图1)。 The region of Mianlianning, Mianxian, Lueyang and Ningqiang counties in the western part of Hanzhong in Shaanxi Province is the intersection of Gansu and Sichuan in the west and the “Triangle” belt of the Mianlianning in the west. The geological structure of the area is complex. In addition to the absence of the Qingbai Estuary, the sequence and lithology of other facies in Sinian sub-region can basically be compared with the Sinian, Jixian and Great Wall series of the Sinian sub-region in southern and northern China . As the Sinian sub-bikin group widely distributed (Figure 1).