Biostratigraphy and palaeoecology of Middle and Late Ordovician conodonts from the Hulo and Yenwashan formations, western Zhejiang, south‐eastern China

Abstract

A total of 5,918 conodonts have been recovered from the upper Hulo Formation and the lower Yenwashan Formation in the Hengdu section, Jiangshan County, Zhejiang Province, south‐eastern China, spanning the interval from the middle Darriwilian to the early Sandbian. Thirty‐three species, belonging to 24 genera, have been identified with three biozones (i.e., the Dzikodus tablepointensis Biozone, the Histiodella kristinae Biozone, and the Pygodus anserinus Biozone) recognized in the region. Using multivariate analysis, the Periodon–Protopanderodus biofacies is recorded from the upper Hulo Formation, and the Periodon–Pygodus biofacies and the Protopanderodus–Baltoniodus biofacies are recorded from the lower Yenwashan Formation. The Periodon–Protopanderodus biofacies and the Periodon–Pygodus biofacies represent a deep‐water environment, such as the margin of the platform and/or slope environment, deeper than that of the Protopanderodus–Baltoniodus biofacies.

Middle Ordovician (Darriwilian) conodonts from southern Tibet, the Indian passive margin: implications for the age and correlation of the roof of the world

“…An et al 1981An et al , 1985Ni & Li, 1987;, 1989Chen et al 1983). Newer information is provided by Wang & Bergström (1995, 1999, Wang et al (1996), Zhang (1998a, b), Chen et al (2006Chen et al ( , 2011, Wu et al (2016Wu et al ( , 2019, Wang et al (2017cWang et al ( , 2019 and summarized by Zhang et al (2019). The stratigraphic nomenclature of Zhan & Jin (2007) and the formally defined conodont zonation by Zhang (1998a) and Wang et al (2019) are used here as evidence for this correlation.…”

“…Species of Histiodella are widely distributed in Asia, including China (e.g. Zhang 1998a; Du et al 2005;Stouge et al 2011;Wang et al 2013c;Jing et al 2016a;Wu et al 2016Wu et al , 2019. The species dealt with here and used for correlation comprise Histiodella holodentata Ethington & Clark, Histiodella sp.…”

“…Except for Histiodella sp. A each of these Histiodella species is the zonal nominate species at zonal or subzonal levels in China, elsewhere in Asia, Argentina and Laurentia (e.g., Stouge 1984Stouge , 2012Feltes et al 2013Feltes et al , 2016Serra et al 2015Serra et al , 2017aSerra et al , b, 2019Jing et al 2016a;Wu et al 2016Wu et al , 2019. Wang et al (2013c) formally introduced Histiodella wuhaiensis recorded from Inner Mongolia (margin of the North China Plate); however, this species is not well known.…”

“…A and Histiodella kristinae are present in the middle to upper part of the Kuniutan Formation Zhang, 1998a). Wu et al (2016Wu et al ( , 2019 recorded Histiodella sp. A (= Histiodella cf.…”

“…A informal zone with the Holmograptus spinosus graptolite Zone (Maletz, 2009;Stouge, 2012;Albanesi & Ortega, 2016;Serra et al 2017aSerra et al , b, 2019, which largely corresponds to the Nicholsonograptus fasciculatus graptolite Zone of South China (Wu et al 2019;Zhang et al 2019). The Histiodella kristinae and H. bellburnensis subzones of the Periodon zgierzensis Zone corresponds to the Nicholsonograptus fasciculatus graptolite Zone and pars the Pterograptus elegans graptolite Zone (Maletz, 2009;Stouge, 2012;Albanesi & Ortega, 2016;Serra et al 2017a, b;Wu et al 2019;Zhang et al 2019). This is equivalent to Stage slice (Dw2) of Bergström et al (2009) and suggests that the main part of the strata of the Lower Formation accumulated during middle Darriwilian time (Fig.…”