TY - JOUR

T1 - Low Geomagnetic Field Paleointensity on the Permian–Triassic Boundary from Study of the Kuznetsk Basin Traps (Southern Siberia)

AU - Eliseev, A. A.

AU - Shcherbakova, V. V.

AU - Metelkin, D. V.

AU - Mikhaltsov, N. E.

AU - Zhidkov, G. V.

AU - Abashev, V. V.

AU - Rogov, A. M.

N1 - Funding Information: This study was financially supported by the RSF (project no. 19-17-00091), the RFBR (projects no. 18-05-70035, 18-05-00234), the Ministry of Science and Higher Education of the RF (project no. FSUS-2020-0039), the state assignment of IPE RAS, and the state assignment for research of Kazan Federal University no. 671-2020-0049. Publisher Copyright: Russian Geology and Geophysics © 2022, Novosibirsk State University.

PY - 2022/2

Y1 - 2022/2

N2 - Here we report the first data on the absolute intensity value of the geomagnetic field on the Permian–Triassic boundary from basalts of the Kuznetsk basin. The latter are considered as one of the manifestations of the initial stage of trap magmatism during the formation of the Siberian large igneous province. The good preservation of information on the ancient geomagnetic field in the Mal’tsevskaya Formation basalts is due to the presence of small single domain and pseudo-single domain grains of primary magmatic titanomagnetite in the groundmass. The paleointensity values obtained following the Thellier-Coe method correspond to the generally accepted criteria of reliability and indicate that the geomagnetic field intensity during the formation of the Kuznetsk basin traps on the Permian–Triassic boundary was almost an order of magnitude lower than the present-day one. Moreover, the mean values of the virtual dipole moment for the Kozhukhta and the Vlasov units in the lower and middle Mal’tsevskaya Formation ((1.9 ± 0.6) ⋅ 1022 A ⋅ m2 and (1.1 ± 0.7) ⋅ 1022 A ⋅ m2, respectively) are in good alignment with determinations of the paleointensity during the accumulation of the Ivakinsky Formation of the Norilsk Region in the Siberian province, which confirms the accuracy of traditional regional correlations.

AB - Here we report the first data on the absolute intensity value of the geomagnetic field on the Permian–Triassic boundary from basalts of the Kuznetsk basin. The latter are considered as one of the manifestations of the initial stage of trap magmatism during the formation of the Siberian large igneous province. The good preservation of information on the ancient geomagnetic field in the Mal’tsevskaya Formation basalts is due to the presence of small single domain and pseudo-single domain grains of primary magmatic titanomagnetite in the groundmass. The paleointensity values obtained following the Thellier-Coe method correspond to the generally accepted criteria of reliability and indicate that the geomagnetic field intensity during the formation of the Kuznetsk basin traps on the Permian–Triassic boundary was almost an order of magnitude lower than the present-day one. Moreover, the mean values of the virtual dipole moment for the Kozhukhta and the Vlasov units in the lower and middle Mal’tsevskaya Formation ((1.9 ± 0.6) ⋅ 1022 A ⋅ m2 and (1.1 ± 0.7) ⋅ 1022 A ⋅ m2, respectively) are in good alignment with determinations of the paleointensity during the accumulation of the Ivakinsky Formation of the Norilsk Region in the Siberian province, which confirms the accuracy of traditional regional correlations.

KW - Kuznetsk basin

KW - Mal’tsevskaya Formation

KW - Mesozoic Dipole Low

KW - paleointensity

KW - Siberian trap province

KW - Thellier-Coe method

UR - http://www.scopus.com/inward/record.url?scp=85127387394&partnerID=8YFLogxK

UR - https://www.elibrary.ru/item.asp?id=48304762

UR - https://www.mendeley.com/catalogue/874e74a1-bdbb-32d9-b443-77b196ba271a/

U2 - 10.2113/RGG20204330

DO - 10.2113/RGG20204330

M3 - Article

AN - SCOPUS:85127387394

VL - 63

SP - 193

EP - 207

JO - Russian Geology and Geophysics

JF - Russian Geology and Geophysics

SN - 1068-7971

IS - 2

M1 - 6

ER -