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Magnetic susceptibility (MS) of the Quaternary long‐term mid‐latitude Maros fluvial fan (Pannonian Basin) was recorded to understand the stratigraphical features of source‐proximal fluvial depositional settings. Three fully cored 500‐m‐deep boreholes were sampled at 0.5‐m intervals; low‐field and frequency dependent MS were measured, and complementary hysteresis and SEM‐EDAX investigations were performed on selected samples. Logged susceptibility data were also used to log correlations established by a simultaneous comparison of wireline log and laboratory measurements. Time‐series analyses of the susceptibility records reveal a ~41‐ka and ~100‐ka cyclicity. Towards the source‐distal sections the intensity of the ~41‐ka cycles decreases, while that of the ~100‐ka cycles remains strong. Stratigraphical and spectral similarities were observed between the Maros fluvial fan and Chinese loess records; however, based on complementary magnetic data, the magnetic phase of the Maros Fan sections is related to the detrital magnetite that originates from the catchment during early postglacial permafrost degradations. The amplification of the ~41‐ka cycles can be attributed to the very high susceptibility values in source‐proximal settings and to the special stratigraphical feature of the distributive fluvial systems. This comprises the increased avulsion frequency on the fluvial fans in ‘glacial recession periods’, in concert with the ‘early postglacial’ occurrence of the permafrost‐related magnetite originating from the catchment. As a local phenomenon, this is significant since it records the obliquity‐driven variations in permafrost development in a catchment. However, fluvial and alluvial fans are widespread depositional landforms within the Eurasian mountain range and were possibly the same during the Quaternary deglaciations. Thus, obliquity‐driven magnetic susceptibility variations in source‐proximal fan deposits attached or adjacent to regions of loess deposition should also be considered when scanning for potential source material of aeolian deposits.

Correlation of the fluvial magnetic susceptibility (MS) record of borehole Devavanya-1 in the Kőrős Basin (eastern Hungary) with Chinese aeolian MS records (Jingbian, Lingtai) and the marine d18O record from the Equatorial Pacific (V28-239) is established here based on cross- orrelations and singular spectral analysis. A basin-scale well-to-well correlation based on magnetic susceptibility records was also performed involving unpublished cores. To refine the age model, a Monte Carlo simulation was conducted using the Chinese Jingbian section as a tuning target. Spectral analysis of the tuned record revealed c. 400, c. 100 and c. 41 ka cycles over the 2.5 million years of the Quaternary fluvial succession. To ensure a complementary palaeoclimate proxy, the full width at half maximum of smectites was measured as a facies-independent indicator of weathering intensity. This investigation was carried out on a subset of samples involved in MS measurements representing a c. 400 ka time interval across the top of the Olduvai subchron. A phase-shift between MS and weathering intensity recorded in the clay mineralogy indicates different response times of the considered proxies. The fluvial MS record is determined by the climatic control on delivery and preservation of magnetic minerals, mainly of magnetite. Under cold-and-dry climate these minerals were released owing to frost shattering in the adjacent hinterlands and were transported to alluvial plains in the early postglacial periods thanks to the increasing discharge of rivers. With further warming the weathering-sensitive magnetic minerals soon disappeared from the soils of the catchment area and thus from the fluvial load. As a result, in fluvial successions early postglacial warmings are expressed by the occurrences of MS maxima (magnetic episodes), while the palaeotemperature maximum and the subsequent cooling remain concealed within the tract of low MS values. The early postglacial magnetic episodes may serve as ideal stratigraphical markers in regional and global correlations.