ABSTRACT
Bingmagou Formation is firstly named by regional geological team of Henan (1964) in 1:0.2 Million Regional Geological Measurement Report of Linrufu Region. It exists in Bingmagou nearby of Yichuan in Henan. The outcrop of Bingmagou Formtaion here is 5 km from east to west, and 100∼1000 m from south to north. Dengfeng Group of Archean is covered in unconformity by it, and Xionger Formation is partly covered in unconformity by it too[1-2]. Maanshan Formation of wufo Group of mesoProterozoic erathem parallel unconformably onlaps it. The section of Bingmagou which is measured is in Wananshan of Lvdian Yichuan. The outcrop of it is very little, and the thickness of it is unstable. From bottom to top the rock grain size of section is from crude to thin section. The distribution of gravel is from close to thin. A sedimentary cycle is formed by the mode of conglomerate-sandy conglomeratesandstone-shale of silt, and secondary rhythm of sedimentary is so much. Parallel bedding and cross bedding could be noticed in sandy conglomerate and sandstone. A similar strata which was named Xiaobeigou Formation was found by Wangzhihong (1979) and the NO 2 geological team of Henan (1981) in Wangwushan of Jiyuan. The time and space and the lithology are considered similar by both regional geological team of Henan (1981) and Regional Geological Book of Henan Province (1989) later time. It should be considered as one Formation, which named by Bingmagou. The outcrop of Bingmagou Formtaion was found better in Wugang too. And the section of Bingmagou which was found recently is in Lushan. The four distribution of Bingmagou Formation metioned
Generally speaking it’s the core of domal structure. The main lithology is plagioclase-hornblend. Schist which is sedimentary normally and low metamorphic consist of the top of Group, and flysch construction could be seen here. The Group lies in Dengfeng County, the lower part of horizon could be seen in Linshan of Jiyuan and Linzhou-Huixian of Taihang mountain area. The upper part of horizon could be seen better in Songshan region. The separatrix of Bingmagou Formation and Dengfeng Group of Archean found on field (Fig. 1).
