the National Natural Science Foundation of China(Grant No.40062001);the Governor Foundation of Guizhou Province;the Post-doctoral Foundation of Guizhou University of Technology and the Excellent Youth Scientists and Technicians Foundation of Guizhou Province,and a special program by MSTC(Grant No.2002CCC02600).
The stratigraphic division and correlation of the Lower/Middle Cambrian boundary is a global problem that has not yet been perfectly solved up to now. That is because there existed two global biogeographic regions dur...