Problems of magnetostratigraphy of Pleistocene loess-soil deposits of the South of Ukraine

Early–Middle Pleistocene Magnetostratigraphic and Rock Magnetic Records of the Dolynske Section (Lower Danube, Ukraine) and Their Application to the Correlation of Loess–Palaeosol Sequences in Eastern and South-Eastern Europe

“…As typical for southern Ukrainian loess [263], the data from thermal demagnetisation seem more informative: there is less scatter between demagnetisation steps, and conformity with the results of neihbouring specimens is observed. Multicomponent analysis of demagnetisation paths revealed that the NRM was composed of two components.…”

“…The ChRM components for most samples separated between 240 °C and 295 °C, and 10-20 mT. In most specimens from the D-S5, D-S6 and D-S7 soil units these stable high temperature components decayed with increasing temperature towards the origin along nearly the same trajectory as the medium temperature components (e.g., Figure 7A-C) As typical for southern Ukrainian loess [263], the data from thermal demagnetisation seem more informative: there is less scatter between demagnetisation steps, and conformity with the results of neihbouring specimens is observed. Multicomponent analysis of demagnetisation paths revealed that the NRM was composed of two components.…”

Magnetostratigraphy and magnetic susceptibility of the best developed Pleistocene loess-palaeosol sequences of Ukraine: implications for correlation and proposed chronostratigraphic models

“…It is dif fi cult in prac tice to conduct chem i cal de mag ne ti za tion on loess sam ples (Liu et al, 2015). AF de mag ne ti za tion is of ten not ef fec tive at re mov ing sec ond ary (vis cous) com po nents from Chi nese (Jin and Liu, 2011;Liu et al, 2015) and Ukrai nian (Bakhmutov and Glavatskiy, 2016) loess, be cause low-tem per a ture ox i da tion of de tri tal mag ne tite can sig nif i cantly in crease its coercivity. In addi tion, the pres ence of superparamagnetic grains in palaeosols Ta ble 3 The po si tion of geo mag netic ex cur sions re corded in the sec tions stud ied does not al low suc cess ful de mag ne ti za tion of the sam ples without plac ing the equip ment in a mag net i cally shielded space.…”

“…Ther mal de mag ne ti za tion be comes the most widely used method to re move sec ond ary com po nents of mag ne ti za tion over prints. Usu ally, in Ukrai nian loess and palaeosols, heat ing of sam ples to 200-250°C is enough to dis tin guish the ChRM com po nent (Bakhmutov and Glavatskiy, 2016).…”

Significance of the Ukrainian loess-palaeosol sequences for Pleistocene climate reconstructions: rock magnetic, palaeosol and pollen proxies

“…The study of the magnetic properties of these rocks began in the 1970s [Tretyak, Volok, 1976;Tretyak, 1980Tretyak, , 1983Tretyak et al, 1987Tretyak et al, , 1989Tretyak, Vigilyanskaya, 1994] and have been continued during the last 20 years [Vigilyanskaya, Tretyak, 2001Bakhmutov et al, 2005Bakhmutov et al, , 2017Bakhmutov, Hlavatskyi, 2014;Bakhmutov, Glavatskіy, 2016;Hlavatskyi et al, 2016a,b;Hlavatskyi, 2019;Hlavatskyi, Bakhmutov, 2019, 2020Nawrocki et al, 1999Nawrocki et al, , 2002Nawrocki et al, , 2016Gendler Fig. 1.…”