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  • Author or Editor: Pethe Mihály x
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Systematic structural and anisotropy of magnetic susceptibility (AMS) measurements were carried out on Cenozoic clay-rich deposits from the Transdanubian Range, central part of the Alcapa Unit. The aim was to improve the knowledge of the Neogene tectonic evolution of the area and of the connection of the stress field and the magnetic fabric of the sediments. The measurements of AMS revealed dominant foliation with weak lineation for Middle Eocene-Lower Miocene sediments. The directions of AMS lineation are aligned either with the direction of NNE-SSW extension of a strike slip phase (30–19 Ma) or with the direction of NE-SW extension of the main rifting phase of the Pannonian Basin (19–14 Ma).The studied Late Miocene sediments have foliated AMS fabric, maximum and intermediate AMS directions are intermixed, and the AMS fabrics do not show any sign of tectonic deformation. In contrast, joints and faults were observed in the same rocks. Detailed structural analysis shows two extensional phases between ca. 10–4 Ma, with E-W to WNW-ESE and with NW-SE extension, respectively, and the youngest neotectonic strike-slip phase. The contrast between the presence of markers of brittle deformation and the absence of tectonically-induced AMS lineation is striking, since the same types of sediments in the South Pannonian basin show just the opposite. The explanation may be that northward-moving and CCW-rotating Adria caused strong compression in the southern Pannonian Basin, resulting in ductile deformation of the clay-rich sediments and systematic reorganization of AMS texture, while in our study area sediments of similar character and age were at a larger distance from the strongly deforming basin part.

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Abstract

Ferromagnetic grains in airborne dust are important indicators of vehicle traffic, some industrial sources and combustion/heating. Settled dust consists mainly of diamagnetic material; therefore accessory ferromagnetic grains are readily indicated by magnetic measurements. In this paper settled dust samples collected on a monthly basis in the years 2008–2011 were studied. Non-destructive magnetic measurements were followed by geochemical and mineralogical analyses. In selected samples we identified airborne anthropogenic materials (e.g. silicate and magnetite spherules), minerals from the natural environment and organic material. Seasonally appearing materials (e.g. soot in winter, plant fragments and pollen in summer) increased the mass of the settled dust, but not the magnetic susceptibility. Thus, we realized that the generally interpreted mass susceptibility in environmental magnetic studies would not always appropriately characterize the magnetic pollution. In the interpretation we gave preference to total susceptibility because of its direct connection to the pollution, except in comparison with metal concentrations.

Trends in magnetic pollution were eventually analyzed for 19 sampling sites. Irrespective of the degree and source of the pollution the monthly variation curves of magnetic susceptibility exhibit a general maximum (March-April), followed by gradual decrease. A corresponding peak is observed in the amounts of dust. Both can be explained by re-suspension of dust settled in winter. The additional maxima in the mass of the dust (June and August, respectively) are probably due to contribution from vegetation and/or an artifact from algaecide. For three key sampling sites comparison was made between the concentrations of 12 metals and the respective mass susceptibilities and good linear correlation was found for Fe, Mn and Zn for all, for Cr, Cu, Pb, V, Ba, Sr and Zr for two sampling sites. Cd, which is enriched in all samples, does not correlate with the magnetic susceptibility.

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Archaeologiai Értesítő
Authors: P. Barna Judit, Tokai Zita Mária, Eke István, Pásztor Emília, T. Biró Katalin, Mesterházy Gábor and Pethe Mihály

Bezeréd-Teleki-dűlő II. lelőhelyen terepbejárás és geofizikai felmérés eredményeként a késő neolitikus lengyeli kultúra körárka vált ismertté. A feltűnően szimmetrikus alaprajzú, kettős körárok mindkét árkán 8–8 bejárat figyelhető meg, melyek némelyike előtt félköríves toldalékok jelentkeztek. A belső árok mindkét oldalán paliszádárkok mutatkoztak. A kapuk tájolása megfelel a dunántúli lengyeli körárkokra jellemző mintázatnak. A körárok belsejében kirajzolódó épületek, a körárok körüli lengyeli kultúrás lelőhelyek, továbbá a körárok időrendi viszonya egyelőre nem tisztázott.

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