The North China Steptoean positive carbon isotope excursion and its global correlation with the base of the Paibian Stage (early Furongian Series), Cambrian

Abstract

The use of carbon isotope excursion in Cambrian stratigraphical correlation is a standard practice at both the intercontinental and intracontinental scales. The Steptoean positive carbon isotope excursion (SPICE) is one of the prime examples in this regard in correlating the base of the Paibian Stage and Furongian Series. A lack of definite SPICE evidence in the North China craton has been a challenge in precision correlation between North China and other palaeo-continents. This study provides new carbonates carbon isotope data from the type locality of the Changshan Formation in Hebei Province, North China. Our new δ13Ccarb data provide new objective evidence for the presence of the SPICE in North China. The sampling section is relatively condensed, and the interval of the SPICE curve is less than one and half-metres after analysing 64 samples (the sampling interval within the SPICE is less than 10 cm). The onset of the SPICE curve in Tangshan, Hebei, occurs in the barren interval between the Neodrepanura and Chuangia trilobite zones. Based on this study and previous work, this could imply the middle part of the Prochuangia-Paracoosia trilobite Zone in North China and can be correlated with the base of the Paibian Stage and Furongian Series.