VOI. 42 NO. 3 SCIENCE IN CHINA (Series D) June 1999 High-resolution Givetian-Frasnian boundary recognition from conodont-chemo-stratigraphic correlation at Liujing , Guangxi, South China JIANG Dayong ( k ) , HA0 Weicheng (@ % ?& ) , DING Gan ( T T ) and BAI Shunliang ( & ) (Department of Geology, Peking University, Beijing 100871 , China) Received September 18, 1998 Abstract The Givetian-Frasnian boundary at Liujing, Guangxi, South China is for the first time recognized and cor- related in high resolution using characteristic chemocycles of element abundance fluctuation integrated with conodont biostratignphy . The first appearance of Ancyodella rot&& early form is as a biomarker, and the bound& of lower- ing fluctuation of element abundance followed by a sequence of characteristic chemocycles with a sequence of cmodonts is as an abiotic auxiliary marker. The error is not more than 0.10 Ma. The study indicates that in a quiet interval, char- acteristic chemocycles integrated with biomarkers can be used for boundary recognition and regional cormlation in high resolution, and this method has potential for intercontinental correlation Keywords: Givetian-Frasnlsn boundary . high rea01ution. correlation , fhemocyde, coaodont . The boundary stratotype for Givetian-Frasnian ( G F ) boundary, i. e . the global stratotype sec- tion and point (GSSP) of Middle Devonian-Upper Devonian series boundary has been ratified at Col du Puech de la Seque Section E in the Montagne Noire, southern France in 1987['-31. The "golden spike " (level of the G F boundary) defined by the first occurrence of conodont Ancy- rodella rotundiloba ( Bryant, 1921 ) early form (Klapper, 1985) is placed at the base of the bed. 42a' . However, there are some arguments about this GSSP[~-~] . The Devo- nian and the G-F boundary beds are well de- veloped in South China, especially at Liujing and Dale in the Guangxi Zhuang Autonomous Region (fig. 1 ) . The urgent task then is to Fig 1 . Location of the Liujing and Dale sections, Guangxi, South recognize the GF boundary and establish the China. reference section at Liujing and Dale in South China, which should agree with international GF standard level and can be correlated with the GSSP in high resolution. The G F boundary at Dale has been studied in but 1 ) Jiang , D . Y . , Conodont zonation and correlation of the GF boundary beds at Liujing , Guangxi (in Chinese with English ab- stract) , Ph . D . Dissertation , Peking University, 1997, Beijing .