TY - JOUR

T1 - The first CA-ID-TIMS U-Pb dating of the Tithonian/Berriasian boundary beds in a Boreal succession

AU - Rogov, M.A.

AU - Panchenko, I.V.

AU - Augland, L.E.

AU - Ershova, V.B.

AU - Yashunsky, V.Yu.

PY - 2023/6/1

Y1 - 2023/6/1

N2 - The Tithonian/Berriasian (T/B) boundary has attracted increasing attention in recent decades, but there are currently only a few numerical ages for this boundary, nearly all of which are derived from sections located in Central and South Americas. Here we present the first reliable geochronological data immediately below the T/B boundary from the West Siberia sedimentary basin, based on the dating of zircon grains derived from a single tuff bed sampled from three different drill cores. This represents the first high precision dates from the latest Jurassic succession of the Panboreal Superrealm. The ages of the studied comagmatic zircon grains from the topmost middle Volgian (equivalent to the middle part of the upper Tithonian) tuffs, based on material from 3 wells, range between 141.83 and 141.11 Ma, where the youngest zircon is interpreted to represent the depositional age of the volcanic horizon. Based on detailed biostratigraphy, our studied succession can be correlated with the middle part of the M20n magnetochron, allowing correlation with coeval J/K boundary successions worldwide. Our data support a re-consideration of the T/B boundary age currently accepted in the international chronostratigraphic chart and are supported by previously published U-Pb ages from Argentina and Mexico.

AB - The Tithonian/Berriasian (T/B) boundary has attracted increasing attention in recent decades, but there are currently only a few numerical ages for this boundary, nearly all of which are derived from sections located in Central and South Americas. Here we present the first reliable geochronological data immediately below the T/B boundary from the West Siberia sedimentary basin, based on the dating of zircon grains derived from a single tuff bed sampled from three different drill cores. This represents the first high precision dates from the latest Jurassic succession of the Panboreal Superrealm. The ages of the studied comagmatic zircon grains from the topmost middle Volgian (equivalent to the middle part of the upper Tithonian) tuffs, based on material from 3 wells, range between 141.83 and 141.11 Ma, where the youngest zircon is interpreted to represent the depositional age of the volcanic horizon. Based on detailed biostratigraphy, our studied succession can be correlated with the middle part of the M20n magnetochron, allowing correlation with coeval J/K boundary successions worldwide. Our data support a re-consideration of the T/B boundary age currently accepted in the international chronostratigraphic chart and are supported by previously published U-Pb ages from Argentina and Mexico.

KW - Berriasian

KW - Numerical age

KW - Tithonian

KW - Volgian

KW - West Siberia

UR - https://www.mendeley.com/catalogue/e78ea093-0187-339f-a59d-4a641f0b75f6/

U2 - 10.1016/j.gr.2023.02.010

DO - 10.1016/j.gr.2023.02.010

M3 - Article

VL - 118

SP - 165

EP - 173

JO - Gondwana Research

JF - Gondwana Research

SN - 1342-937X

ER -