Genesis of the Cambrian-Ordovician dolostones in the eastern Tarim Basin,Xinjiang

The laterally persistent dolostones in the eastern Tarim Basin,Xinjiang are of important significance of research.Three genetic models are constructed on the basis of lithology,carbon and oxygen isotopes,strontium isotopic ratios,and ordering degree.The penecontemporaneous micritic dolostones are generated by the sea-water pumping due to tidal effects in the subtidal reducing conditions during the penecontemporaneous stages.The fine-to medium-crystalline dolostones and coarse-crystalline dolostones result from regulation dolomitization in the burial diagenetic conditions,and hydrothermal dolomitization in the deeper parts.