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This paper briefly summarizes an officially ratified Global Standard Stratotype-section and Point(GSSP) and a proposed GSSP for global stages of the Cambrian System.The Luoyixi section near Luoyixi town,Guzhang,northwestern Hunan is ratified as the boundary stratotype for the base of the global Guzhangian Stage,which is the upmost stage of an unnamed series termed provisionally as Cambrian Series 3.The GSSP position lies 121.3 m above the base of the Huaqiao Formation in the section,coinciding with the first appearance of the cosmopolitan agnostoid trilobite Lejopyge leavigata. The Duibian B section at Duibian village,Jiangshan,western Zhejiang,is proposed as the boundary stratotype for the base of the proposed global Jiangshanian Stage that is the second stage of the Furongian Series.The proposed GSSP position lies 108.12 m above the base of the Huayansi Formation in the section,coinciding with the first appearance of the cosmopolitan agnostoid trilobite Agnostotes orientalius.This horizon is also with the first appearance of the cosmopolitan polymerid trilobite Irvingella angustilimbata.
This paper briefly summarizes an officially ratified Global Standard Stratotype-section and Point (GSSP) and a proposed GSSP for global stages of the Cambrian System. Luoyixi section near Luoyixi town, Guzhang, northwestern Hunan is ratified as the boundary stratotype for the base of the global Guzhangian Stage, which is the upmost stage of an unnamed series termed provisionally as Cambrian Series 3. The GSSP position lies 121.3 m above the base of the Huaqiao Formation in the section, coinciding with the first appearance of the cosmopolitan agnostoid trilobite Lejopyge leavigata The Duibian B section at Duibian village, Jiangshan, western Zhejiang, is proposed as the boundary stratotype for the base of the proposed global Jiangshanian Stage that is the second stage of the Furongian Series. The proposed GSSP position lies 108.12 m above the base of the Huayansi Formation in the section, coinciding with the first appearance of the cosmopolitan agnostoid trilobite Agnostotes orientalius.This ho rizon is also with the first appearance of the cosmopolitan polymerid trilobite Irvingella angustilimbata.