Why is intercontinental correlation within the Lower Cambrian so difficult?

نویسندگان

چکیده

Correlation of Lower Cambrian rocks is hampered because there are no widespread and rapidly evolving organisms such as the later agnostids, graptolites, conodonts, ammonites, or planktonic foramini fers, that might provide basis for a consistent intercontinental biostratigraphy. Four problems illustrate issue: 1) age oldest trilobites China; 2) acritarch correlations between Siberia Baltica; 3) conflicts archaeocyath trilobite correlations; 4) location Cambrian/Middle boundary. There an internationally useful set stages at this time.

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ژورنال

عنوان ژورنال: Spanish journal of palaeontology

سال: 2022

ISSN: ['2660-9568', '2255-0550']

DOI: https://doi.org/10.7203/sjp.23974