太行山地区三山子白云岩沉积层序及矿产

Depositional Sequences and Minerals of Sanshanzi Dlostone in Taihang Mountains

三山子白云岩是一个分布非常广泛的穿时岩石地层单位，在太行山北段可以追索到它与下奥陶统冶里组和亮甲山组间的指状接触关系，中、南段，它下穿到凤山阶地层。三山子白云岩是受寒武纪－早奥陶世二级旋回海平面降低及古气候条件控制而形成的岩石地层体。由于古地理背景的差异，导致了三山子白云岩的岩相及区域分布的特殊性，从而表明了南高北低的古地理特征。三山子白云岩就是在这样南浅北深的沉积环境中伴随着三次三级海平面升降变化沉积及白云岩化作用而形成的岩层体。

anshanzi dolostone is a diachronous lithostratigraphic unit that is widespread. Thefingernail contact relationship between Sanshanzi dolostone and Yieli-Liangjiashan Formations oflow ordovician Series may be investigated in North area of Taihang Mountains. In South andMiddle Taihang Mountains, its base boundary surface crosses downwards Fengshan Stage. Sanshanzi dolostone is a lithostratigraphic body, whose genetation is dominated by paleoclimat andsea-level falling of second order cycle from Cambrian pened to early Ordovician Epoch. Owing tothe difference of the paleogagraphic setting, the lithofacies and arearial distribution of Sanshanzidolostone show distinctive features: the sea between shoals, shoal and tidal flat factes distributesmainly in Fengfeng area; sabkha and tidal flat factes distribute in the upper part of section, shoalfactes in the lower part of section in Jingxing aera; the ramp and restricted sea factes distributemainly in Laiyuan and Quyang aera, which show the paleogeographic nature of the falling fromSouth toward North. Sanshanzi dolostone is a lithestratigraphic they which was formed by thedePOsition and dolonlzation, with the three third order sea-level change in the sedimentary enviornment being shallow in South and deep in North.