汝州阳坡的洛峪口组

THE LUOYUKOU FORMATION IN YANGPO OF RUZHOU

汝州阳坡一带的洛峪口组，归属于上元古界洛峪群。洛峪口组自下而上可划分出四个岩性段，其中一、二段相当于汝阳洛峪口村附近建组剖面上的洛峪口组，三、四段则为汝州地区新发现的地层，它们之间均呈整合接触关系，时代归属晚元古代青白口纪。洛峪口组四个段，在岩性组合上具有较强的规律性，反映出潮下、潮间、潮上的沉积环境交替出现。海平面振荡频繁，发育三个Ⅱ类层序，除Ⅱ３顶部为Ⅰ型层序界面外，其他层序的顶底界面均为Ⅱ型层序界面。三个层序均具有共同的沉积特征，海侵体系域不发育。

The Luoyukou Formation of the Upper Proterozoic Luoyu Group in Yangpo of Ruzhou can be divided into four members in ascending order according to the lithologic assemblage. The first and second members correspond to the Luoyukou Formation in the section proposed the Formation near Luoyukou village of Ruyang, the third and fourth members belong to the new discovered strata in Ruzhou area. These four members are all conformable each other,and all belong to Qingbaikou period of the Late Proterozoic era, and have more distinct regularity on the lithologic assemblage, indicating the sedimentary environments of subtide, intertide and supratide occured alternately, and the sea level has taken place much more oscillatory movement frequently. Three Ⅱ type sequences have been built. The top and bottom surfaces of these sequences all belong to the Ⅱ type sequence boundary lines except that the top surface of the third sequence which are the Ⅰ type sequence boundary line. These sequences all have same sedimentary character that transgressive system tracts are not development and the condensed sections occured in the lower horizon.