勘探三队及地质物探队,在涇河流域某坝段进行工程地质测繪中,发現在中奧陶統的上部,覆盖一套深灰色厚层石灰岩,呈不等粒結构,出露厚度各处不一,最厚达443米。从中采得数种海相动物化石,經西北地貭科学研究所鉴定,其中有一种是Favistella inter- In the upper part of the Middle Ordovician, an exploration team and a geophysical team were enrolled in a geological survey of a dam in the Jinghe River basin to cover a set of dark gray thick limestone with unequal grain structure and exposed thickness Different locations, the maximum thickness of 443 meters. Several marine animal fossils have been collected from them and identified by the Northwest Institute of Dioscorea, one of which is Favistella inter-