{"title":"Global correlation of the Guadalupian–Lopingian transition and associated events using a quantitative conodont-based biostratigraphic scheme","authors":"Shu-han Zhang , Dong-xun Yuan , Shu-zhong Shen","doi":"10.1016/j.palaeo.2024.112502","DOIUrl":null,"url":null,"abstract":"<div><p>The Guadalupian–Lopingian boundary (GLB) interval contains global-scale changes in biota and environment. The establishment of a uniform time scale and a robust system of global correlation are critical in order to unravel the tempo of these events. Conodonts are key biostratigraphic tools; however, major discrepancies exist in conodont taxonomy and correlation in this interval. In this paper, we compile conodont data from 17 well-studied sections in South China, Japan, Oman and North America, comprising 206 occurrences and 100 species, based on previous publications and our own revisions, to test the reproducibility and correlation value of formerly established interval zones. The Unitary Association method (UAM), a quantitative stratigraphic method for the construction of biozones, is applied to construct a robust conodont biozonation for the GLB. Eleven unitary associations (UAs) and eight unitary association zones (UAZs) are recognized to establish biozones and the GLB was constrained within the UAZ5. According to the reproducibility of these UAZs, the correlation of the Lopingian is generally better than the Guadalupian. Apparent contradictions revealed by the UAZs suggest that biostratigraphic and/or taxonomic issues are present within the <em>Clarkina liangshanensis</em>, <em>C. leveni</em>, <em>C. transcaucasica</em> interval zones. The interval between UAZ4 and UAZ5 records the conodont turnover event from <em>Jinogondolella</em> to <em>Clarkina</em> in the paleoequatorial region. Our results suggest that the UAZs are more reliable for correlation. By contrast, some taxonomic and phylogenetic issues are present in the interval zones based on the conodont succession around the GLB. Although at a coarser stratigraphic resolution, removing all the contradictions enables UAZs to better correlate global sections compared with interval zones. The newly established UAZs indicate that the previously reported isotope excursions around the GLB in different regions may be temporally inconsistent.</p></div>","PeriodicalId":19928,"journal":{"name":"Palaeogeography, Palaeoclimatology, Palaeoecology","volume":"655 ","pages":"Article 112502"},"PeriodicalIF":2.6000,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Palaeogeography, Palaeoclimatology, Palaeoecology","FirstCategoryId":"89","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0031018224004917","RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"GEOGRAPHY, PHYSICAL","Score":null,"Total":0}
引用次数: 0
Abstract
The Guadalupian–Lopingian boundary (GLB) interval contains global-scale changes in biota and environment. The establishment of a uniform time scale and a robust system of global correlation are critical in order to unravel the tempo of these events. Conodonts are key biostratigraphic tools; however, major discrepancies exist in conodont taxonomy and correlation in this interval. In this paper, we compile conodont data from 17 well-studied sections in South China, Japan, Oman and North America, comprising 206 occurrences and 100 species, based on previous publications and our own revisions, to test the reproducibility and correlation value of formerly established interval zones. The Unitary Association method (UAM), a quantitative stratigraphic method for the construction of biozones, is applied to construct a robust conodont biozonation for the GLB. Eleven unitary associations (UAs) and eight unitary association zones (UAZs) are recognized to establish biozones and the GLB was constrained within the UAZ5. According to the reproducibility of these UAZs, the correlation of the Lopingian is generally better than the Guadalupian. Apparent contradictions revealed by the UAZs suggest that biostratigraphic and/or taxonomic issues are present within the Clarkina liangshanensis, C. leveni, C. transcaucasica interval zones. The interval between UAZ4 and UAZ5 records the conodont turnover event from Jinogondolella to Clarkina in the paleoequatorial region. Our results suggest that the UAZs are more reliable for correlation. By contrast, some taxonomic and phylogenetic issues are present in the interval zones based on the conodont succession around the GLB. Although at a coarser stratigraphic resolution, removing all the contradictions enables UAZs to better correlate global sections compared with interval zones. The newly established UAZs indicate that the previously reported isotope excursions around the GLB in different regions may be temporally inconsistent.
期刊介绍:
Palaeogeography, Palaeoclimatology, Palaeoecology is an international medium for the publication of high quality and multidisciplinary, original studies and comprehensive reviews in the field of palaeo-environmental geology. The journal aims at bringing together data with global implications from research in the many different disciplines involved in palaeo-environmental investigations.
By cutting across the boundaries of established sciences, it provides an interdisciplinary forum where issues of general interest can be discussed.