摘要
This study represents the chemostratigraphical work on limestones covering the Polygnathus xylus ensensis to lower varcus zones at Liujing section, Guangxi, South China. In conjunction with biostratigraphic abservations, values/contents and trends of Ce/La, Ni/La, δ13Ccarb of unaltered limestones presented in this study provide the most powerful biochemostratigraphic tool in recognizing a series of anoxic events, Nickel-events and bio-events. Together with the large positive excursion of δ13Ccarb just on the Eifelian-Givetian boundary reflecting higher productivity and burial of organic matter, the essentially pronounced negative excursions near the boundary relating to the global kacak-otomari event are well correlated by those of Volf Gorge and U dubu sedmi bratri in the Barrandian Basin, Czech Republic.