Paleointensity determination on Neoarchaean dikes within the Vodlozerskii terrane of the Karelian craton

• Published in: Izvestiya. Physics of the solid earth Vol. 53; no. 5; pp. 714 - 732
• Main Authors: Shcherbakova, V. V., Lubnina, N. V., Shcherbakov, V. P., Zhidkov, G. V., Tsel’movich, V. A.
• Format: Journal Article
• Language: English
• Published: Moscow Pleiades Publishing 01-09-2017; Springer Nature B.V
• Subjects: Contact; Cratons; Dikes; Dipole moments; Earth and Environmental Science; Earth Sciences; Embankments; Geophysics/Geodesy; Magnetism; Paleoecology; Paleomagnetic studies; Paleomagnetism; Precambrian; Ultrasonic testing; Karelian craton; paleointensity; Thellier technique; Neoarchaean dikes; paleodirections
• ISSN: 1069-3513; 1555-6506
• DOI: 10.1134/S1069351317050111

The results of paleomagnetic studies and paleointensity determinations from two Neoarchaean Shala dikes with an age of ~2504 Ma, located within the Vodlozerskii terrane of the Karelian craton, are presented. The characteristic components of primary magnetization with shallow inclinations I = −5.7 and 1.9 are revealed; the reliability of the determinations is supported by two contact tests. High paleointensity values are obtained by the Thellier–Coe and Wilson techniques. The calculated values of the virtual dipole moment (11.5 and 13.8) × 10
22
A m
2
are noticeably higher than the present value of 7.8 × 10
22
A m
2
. Our results, in combination with the previous data presented in the world database, support the hypothesized existence of a period of high paleointensity in the Late Archaean–Early Proterozoic.