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We demonstrate the use of the anisotropy of magnetic susceptibility (AMS) method to determine the orientation of the principal tectonic strain directions developed during the formation of the West Spitsbergen Fold-and-Thrust Belt (WSFTB). The AMS measurements and extensive rock-magnetic studies of the Lower Triassic rocks reported here were focused on the recognition of the magnetic fabric, the identification of ferromagnetic minerals and an estimation of the influence of ferro- and paramagnetic minerals on magnetic susceptibility. At most sites, the paramagnetic minerals controlled the magnetic susceptibility, and at only one site the impact of ferromagnetic minerals was higher. The AMS technique documented the presence of different types of magnetic fabrics within the sampled sites. At two sites, a normal (Kmin perpendicular to the bedding) magnetic fabric of sedimentary origin was detected. This was associated with a good clustering of the maximum AMS axes imposed by tectonic strain. The Kmax magnetic lineation directions obtained here parallel the general NNW–SSE trend of the WSFTB fold axial traces and thrust fronts. The two other investigated sites possessed mixed and inverted fabrics, the latter of which appear to reflect the presence of iron-bearing carbonates.

Industrial and urban dusts were characterized by investigating their magnetic properties. Topsoil composed of technogenic magnetic particles (TMP) originating from areas affected by three ironworks, street dust mainly composed of traffic-related pollution, and particulate matter (PM) from urban agglomeration in Warsaw, Poland were investigated. Several magnetic methods, namely magnetic susceptibility, thermomagnetic curves, hysteresis loops, decomposition of isothermal remanent magnetization acquisition curves, and first-order reversal curves, were performed to evaluate the magnetic fraction of dust. Magnetite was the main magnetic phase in all types of samples, with a small amount of high-coercive hematite within ironworks and street dust samples. Significant differences were observed in the domain structure (grain size) of industrial and traffic-related magnetic particles. The grain size of TMP obtained from steel production was in the range of 5–20 µm and was predominated by a mixture of single-domain (SD) and multidomain (MD) grains, with the prevalence of SD grains in the topsoil affected by Třinec ironwork. The traffic-related dust contained finer grains with a size of about 0.1 µm, which is characteristic of the pseudo-single-domain (PSD)/SD threshold. Street dusts were composed of a slightly higher proportion of MD grains, while PM also revealed the typical behavior of superparamagnetic particles.