TY - JOUR
T1 - Cambrian Explosion Condensed: High-Precision Geochronology of the Lower Wood Canyon Formation, Nevada
T2 - High-precision geochronology of the lower Wood Canyon Formation, Nevada
AU - Nelson, Lyle L.
AU - Crowley, James L.
AU - Smith, Emily F.
AU - Schwartz, Darin M.
AU - Hodgin, Eben B.
AU - Schmitz, Mark D.
PY - 2023/7/25
Y1 - 2023/7/25
N2 - The geologically rapid appearance of fossils of modern animal phyla within Cambrian strata is a defining characteristic of the history of life on Earth. However, temporal calibration of the base of the Cambrian Period remains uncertain within millions of years, which has resulted in mounting challenges to the concept of a discrete Cambrian explosion. We present precise zircon U–Pb dates for the lower Wood Canyon Formation, Nevada. These data demonstrate the base of the Cambrian Period, as defined by both ichnofossil biostratigraphy and carbon isotope chemostratigraphy, was younger than 533 Mya, at least 6 My later than currently recognized. This new geochronology condenses previous age models for the Nemakit–Daldynian (early Cambrian) and, integrated with global records, demonstrates an explosive tempo to the early radiation of modern animal phyla.
AB - The geologically rapid appearance of fossils of modern animal phyla within Cambrian strata is a defining characteristic of the history of life on Earth. However, temporal calibration of the base of the Cambrian Period remains uncertain within millions of years, which has resulted in mounting challenges to the concept of a discrete Cambrian explosion. We present precise zircon U–Pb dates for the lower Wood Canyon Formation, Nevada. These data demonstrate the base of the Cambrian Period, as defined by both ichnofossil biostratigraphy and carbon isotope chemostratigraphy, was younger than 533 Mya, at least 6 My later than currently recognized. This new geochronology condenses previous age models for the Nemakit–Daldynian (early Cambrian) and, integrated with global records, demonstrates an explosive tempo to the early radiation of modern animal phyla.
KW - Cambrian explosion
KW - Ediacaran-Cambrian boundary
KW - U-Pb geochronology
KW - carbon isotope excursions
KW - geologic time scale
UR - https://scholarworks.boisestate.edu/geo_facpubs/780
UR - http://www.scopus.com/inward/record.url?scp=85165064847&partnerID=8YFLogxK
U2 - 10.1073/pnas.2301478120
DO - 10.1073/pnas.2301478120
M3 - Article
C2 - 37459545
VL - 120
SP - e2301478120
JO - Proceedings of the National Academy of Sciences
JF - Proceedings of the National Academy of Sciences
IS - 30
ER -