Carbon isotope and magnetic polarity evidence for non-depositional events within the Cambrian-Ordovician Boundary section near Dayangcha, Jilin Province, China

Abstract

Abstract-Carbon isotope and magnetic polarity stratigraphic results from the Cambrian-Ordovician Boundary section at Xiaoyangqiao, near Dayangcha, Jilin Province, China, in comparison to a contemporaneous section at Black Mountain, Australia, indicate strata equivalent to major portions of the Australian sequence are either absent or are restricted to highly condensed intervals. These intervals are correlative with regressive sea level events identified in Australia and western orth America, suggesting regional or eustatic sea level changes strongly influenced deposition of the Xiaoyangqiao sequence. These results also suggest the Xiaoyangqiao section is unfavourable as the site of the Cambrian-Ordovician Boundary Global Stratotype Section and Point.

Proposed stratotype for the base of the Lawsonian Stage (Cambrian Stage 10) at the First Appearance Datum of Eoconodontus notchpeakensis (Miller) in the House Range, Utah, USA

“…5) produced a carbon-isotope profile from the Tarim Plateau in far western China and used conodont biostratigraphy to assist their correlations to other areas. They obtained carbon-isotope profiles from the Dayangcha section in Jilin Province, China (Ripperdan et al 1993, Chen et al 1995, from the Green Point section in Newfoundland, Canada (Cooper et al 2001), and from the Black Mountain section in Queensland, Australia and the Lawson Cove section in Utah (Ripperdan & Miller 1995).…”

The SPICE carbon isotope excursion in Siberia: a combined study of the upper Middle Cambrian–lowermost Ordovician Kulyumbe River section, northwestern Siberian Platform

“…Although the carbon isotopic record from the Cambrian-Ordovician boundary stratotype at Green Point seems to be distorted by diagenesis (Cooper, Nowlan & Williams, 2001), a combination of data from other sections, such as Dayangcha in China (Ripperdan, Magaritz & Kirschvink, 1993), Black Mountain in Australia Miller et al 2006) and Lawson Cove in Utah (Ripperdan & Miller, 1995;Miller et al 2006) enabled a generalized (global) curve to be compiled (Cooper, Nowlan & Williams, 2001, fig. 4; Fig.…”

“…Upper Cambrian-Lower Ordovician magnetostratigraphic results from several sections, such as the Black Mountain in Australia , Dayangcha (Ripperdan, Magaritz & Kirschvink, 1993) and Tangchan (Yang et al 2002) in China, Green Point in western Newfoundland, Bartyrbay in Kazakhstan, and from Texas (Ripperdan & Kirschvink, 1992) do not, however, provide a standardized magnetostratigraphic scale through the Cambrian-Ordovician interval (Cooper, Nowlan & Williams, 2001). A tentative correlation of magnetostratigraphic zones of the Upper Cambrian-Lower Ordovician of China and Australia with the Kulyumbe section was suggested by Pavlov & Gallet (2005).…”

Carbon isotope composition and correlation across the Cambrian-Ordovician boundary in Kalpin Region of the Tarim Basin, China

“…Since the 1990s, research of stable carbon isotope profiles combined with conodont biostratigraphy has made remarkable progress [4][5][6][7][8][9][10] . At several international key sections of the Cambrian-Ordovician boundary well-marked relations have been established for large intercontinental areas.…”

“…At several international key sections of the Cambrian-Ordovician boundary well-marked relations have been established for large intercontinental areas. Nevertheless, in China, research on systematic and high-resolution carbon isotope stratigraphy was carried out only at the Dayangcha section [5,8,11,12] located in Hunjiang (Baishan today) of the Jilin Province, as one of the GSSP candidate sections for the Cambrian-Ordovician boundary. But because of the several depositional breaks within the boundary interval, correlation of carbon isotope curve of the Dayangcha section [5] with sections outside of China is not very satisfactory.…”