Geological Characteristics and Significance of Glauconites in Stromatolite Rock-Reef of Mesoproterozoic Tieling Formation in Jixian County

Gglauconite,as a special indicative-facies mineral,has in terested geologists for some time.The Phanerozoic glauconites in this study show that they were formed in an environment of weak reduction and low sedimentation.However,the glauconites in stromatolite rock-reef of the Mesoproterozoic Tieling formation in the Jixian county were formed in a form of filmat the contact between stromato lite pillars and situated in a early high standard system tract (EHST) of the second member of the Tieling formation.This may imply a special benthal cementation and a normal,shallow marine environment,may be an insufficient oxygen environment,in the Precam brian (about 100 Ma).