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S U M M A R YSeveral rock magnetic properties are reported for remagnetized biohermal carbonate rocks, platform carbonate rocks and siliciclastic rocks from the NE Rhenish massif, Germany. Thermal demagnetization of a triaxial isothermal remanent magnetization (IRM) applied at room temperature identifies a variety of magnetic minerals in the sample set. Magnetite is the predominant magnetic phase and carries a Late Palaeozoic remagnetization component and can be accompanied by haematite and pyrrhotite as the carrier of remagnetization. High haematite contents are characteristic for samples carrying a remagnetization of Triassic age. Zero field heating of remanence acquired at 10 K indicates significant contribution from magnetic material with blocking temperatures between 10 and 100 K. The Verwey transition at 120 K is much more pronounced in siliciclastic rocks than in carbonate rocks and is presumably related to the presence of detrital multidomain (MD) magnetite. Samples from biohermal carbonate rocks have hysteresis properties with high M rs /M s and H cr /H c ratios similar to those from remagnetized carbonate rocks from North America. In those lithologies, the intensity decrease of a low temperature IRM during heating from 10 to 100 K combined with the absence of paramagnetic minerals, high hysteresis ratios, magnetic viscosity and frequency dependence of susceptibility give strong evidence for the presence of superparamagnetic (SP) magnetite. This supports the hypothesis of a chemical remagnetization event in the NE Rhenish massif during the Late Carboniferous. The rock magnetic properties of siliciclastic rocks are characterized by high amounts of paramagnetic material and MD magnetite. MD material obscures the contributions of other material to the bulk magnetic properties completely in most siliciclastic rocks and partly in platform carbonate rocks.

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[1] The paleogeography of the Altaids and its kinematic and tectonic evolution during the final collision and amalgamation of Eurasia is still poorly known. Addressing this problem, a paleomagnetic study has been undertaken on Paleozoic sedimentary rocks from the Karatau, Southern Kazakhstan. Stepwise thermal demagnetization reveals the presence of a high-temperature component of magnetization in most samples. Fold tests indicate a syn-folding age of magnetic remanence acquisition at three of the five areas studied. Directional data of Devonian and Permian rocks yield a positive fold test, implying a primary magnetization. Resulting prefolding paleolatitudes for Permian and Devonian rocks show the proximity of the Karatau to Baltica during those times. Syn-and post-folding magnetizations result in paleolatitudes for Karatau, which intersect the paleolatitude curve based on the Baltica apparent polar wander path (APWP), at times, which can be correlated to major deformational events at 280 Ma, 260 Ma, and 230 Ma, respectively. We interpret this with complicated pattern of remagnetization events accompanying deformation, which can include syn-folding remagnetization events and areas of primary magnetic signals. Additionally, the differences between reference declinations based on the APWP for Baltica and observed declinations suggest successive counterclockwise rotational reorganization of the Karatau during the late Paleozoic to Early Mesozoic, with maximal rotation values of 65 ı with respect to Baltica. The remagnetization events are correlated with latest intracontinental stages of orogenic evolution in the Ural mountains and thus the Paleozoic amalgamation of the Eurasian continent and suggest synchronous and coherent tectonic evolution in the Urals and Karatau mountains.