A certain amount of bioherm are developed in the Lower Silurian Shiniulan Formation in southeastern Chongqing.Taking the Jiqiangtai outcrop in Wansheng of Chongqing and Houtan outcrop in Xishui of Guizhou as the main study targets

we studied in detail the bioherm in the Lower Silurian Shiniulan Formation through field observation

ordinary thin section observation and carbon/oxygen isotope measurement.The bioherms mainly occur in the Upper and Middle Shiniulan in the study area and have a certain scale.Rock structure and carbon/oxygen isotopes reveal a change of sea level from slow rising to sharp declining.Depositional environment developed from shallow mixed continental shelf in the early stage to biological reef-shoal in the middle stage and finally to reef-front slope in the late stage.The aquatic environment was suitable for the coral bioherms and biological communities to thrive.The development of bioherm in the Lower Silurian Shiniulan in southeastern Chongqing was mainly affected by sea-level changes and terrigenous clastics input.Slow change of sea level was the basic condition for bioherm growth and the amount of terrigenous clastics input controlled the process of bioherm development.