Magnetic enhancement model for southern Ukraine loess on the example of the Middle Pleistocene sequence at Dolynske

• Datum: 2025
• 1. Verfasser: Hlavatskyi, D.V.
• Format: Artikel
• Sprache: Ukrainisch
• Veröffentlicht: S. Subbotin Institute of Geophysics of the NAS of Ukraine 2025
• Schlagworte: Danube basin; loess-palaeosol sequence; magnetic susceptibility; rock magnetism; pedogenic model; Mid-Brunhes transition
• Online Zugang: https://journals.uran.ua/geofizicheskiy/article/view/323058
• Назва журналу: Geofizicheskiy Zhurnal

Rock magnetic parameters of loess-palaeosol sequences, primarily, magnetic susceptibility and its frequency-dependence factor, play a significant role in the Pleistocene climate studies. Usually, the interpretation of loess magnetic patterns is based on two commonly accepted models: the pedogenic («Chinese») magnetic enhancement and reducing-pedogenic («Alaskan») models. However, there is an increasing number of cases where each model cannot be applied alone (the so-called transitional model), in particular in northwestern Ukraine. This study provides rock magnetic data from the Middle Pleistocene loess sequence at Dolynske in southern Ukraine. Combined with previously obtained data from the Roksolany and other sections in the region, the results show high concentration of ferrimagnetic minerals, in particular, superparamagnetic magnetite, in palaeosols. This proves the predominance of the typical pedogenic magnetic enhancement model for southern Ukraine, as well as for the most of Ukraine. According to the rock magnetic indices, in the Middle Pleistocene, seven interglacials were identified in the interval of the loess-soil series of southern Ukraine. They correspond to the marine isotope stages MIS 19, MIS 17, MIS 15, MIS 13, MIS 11, MIS 9, and MIS 7. The rhythms have been established for individual climatic optima (interstadials), particularly for MIS 15e, MIS 15a, MIS 13c, MIS 13a, MIS 9e, MIS 9a, MIS 7e, and MIS 7a—c, which are clearly detected by magnetic methods. The paper considers several (chrono-)stratigraphic problems in the Middle Pleistocene loess formation of southern Ukraine and compares palaeogeographic stages of the Ukrainian climatostratigraphic system with major global and regional palaeoclimatic trends.