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[1] We report on new paleomagnetic and anisotropy of magnetic susceptibility (AMS) data from Plio-Pleistocene sedimentary units from Corinth and Megara basins (Peloponnesus, Greece). Paleomagnetic results show that Megara basin has undergone vertical axis CW rotation since the Pliocene, while Corinth has rotated CCW during the same period of time. These results indicate that the overall deformation in central Greece has been achieved by complex interactions of mostly rigid, rotating, fault bounded crustal blocks. The comparison of paleomagnetic results and existing GPS data shows that the boundaries of the rigid blocks in central Greece have changed over time, with faulting migrating into the hanging walls, sometimes changing in orientation. The Megara basin belonged to the Beotia-Locris block in the past but has now been incorporated into the Peloponnesus block, possibly because the faulting in the Gulf of Corinth has propagated both north and east. Paleomagnetic and GPS data from Megara and Corinth basins have significant implications for the deformation style of the continental lithosphere. In areas of distributed deformation the continental lithosphere behaves instantaneously like a small number of rigid blocks with well-defined boundaries. This means that these boundaries could be detected with only few years of observations with GPS. However, on a larger time interval the block boundaries change with time as the active fault moves. Paleomagnetic studies distinguishing differential rotational domains provide a useful tool to map how block boundaries change with time.

[1] Eight historical dacitic lava flows from Santorini with ages between 46 A.D. and 1950 A.D. (four of them within the past century) have been subjected to detailed rock magnetic analyses and various experiments of absolute paleointensity. Thermomagnetic measurements and acquisition of isothermal magnetization have revealed the presence of two physically distinct magnetic phases with Curie temperatures of 280°C and 500°C. In most of the samples, the second phase does not play a prominent role for the characteristic remanent magnetization, which is dominated by titanomagnetite. Magnetostatic interaction is very limited and does not considerably change upon heating. Back-field curve spectra indicate a good thermochemical stability of these dacitic lava samples, which is also supported by the absence of noticeable changes in the remanent coercive force prior heating to 450°C. Hysteresis measurements show typical pseudo-singledomain behavior without noticeable superparamagnetism. Such characteristics were favorable to conduct and to test the most widely used experimental approaches for absolute paleointensity determination. Despite a success rate of 38%, the microwave technique has provided rather scattered within-flow determinations. The results obtained from approaches involving alternating field demagnetization were biased by considerable differences between the NRM and the TRM coercive force spectra. We have also noticed that most determinations obtained by microwave heating differ from the historical field value at the site for the most recent flows. Last, techniques involving double-heating protocols were successful due to a dominant Copyright 2010 by the American Geophysical Union 1 of 22 low Curie temperature phase with a narrow grain size distribution. The results were characterized by low dispersion and were found in good agreement with the historical field.

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The present article comprises a multidisciplinary archaeometric approach for the study of Hellenistic and Early Roman kilns in Greece. A collection of previously published and new archaeomagnetic data are combined with new results from mineralogical analytical experiments. The sampled material came from four areas, covering different geological contexts: Katerini, Olympiada, and Polymylos in mainland Greece, and the island of Paros. Extensive rock-magnetic experiments, including identification of the dominant ferromagnetic minerals present, their domain state, and mineralogical alterations during laboratory treatments, have been carried out in order to examine the magnetic properties of the studied materials and prove their suitability for reliable archaeomagnetic determinations. Magnetic cleaning provided well-defined archaeomagnetic directions, and archaeointensity measurements were carried out using both the Thellier-Thellier and Triaxe protocols. Information from both magnetic and mineralogical properties referring to firing conditions is further discussed along with archaeological information. Finally, a new dating of the four sites together with other structures of similar age was carried out using the Pavón-Carrasco model.