Archaeomagnetic investigations in Bolgar (Tatarstan)

Archaeomagnetic investigations at the UNESCO World Heritage site of Bolgar, Tatarstan, have yielded high-quality geomagnetic field data for the period 1340–1360 C.E., contributing a well-dated point to the future palaeosecular variation (PSV) reference curve for western Russia. The study introduced innovations in palaeointensity analysis, including a redefined check for blocking/unblocking temperature equality and Bayesian approaches to average specimen archaeointensities while correcting for cooling rate effects, reducing uncertainty without time-consuming experiments. Magnetic mineralogy analysis revealed stable maghaemite, multi-domain haematite, and Al-substituted haematite, with congruent directions from alternating field demagnetisation and archaeointensity experiments. The results align with global geomagnetic models and regional PSV data, underscoring Bolgar's significance for geomagnetic research.

Kosareva, L. R., Kuzina, D. M., Nurgaliev, D. K., Sitdikov, A. G., Luneva, O. V., Khasanov, D. I., Suttie, N., & Spassov, S. (2020). Archaeomagnetic investigations in Bolgar (Tatarstan). Studia Geophysica et Geodaetica, 64(2), 255–292. https://doi.org/10.1007/s11200-019-0493-3