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In this study we utilize regional and teleseismic earthquake moment tensor solutions in order to infer the contemporary crustal stress in the Greek region. We focus on crustal earthquakes and select only solutions with good waveform fits and well-resolved nodal planes. A data set of 1614 focal mechanisms is used as input to a regional-scale damped stress inversion algorithm over a grid whose node spacing is 0.35°. Several resolution and sensitivity tests are performed in order to ascertain the robustness of our results. Our findings show that for most of the Greek region the largest principal stress σ1 is vertically oriented and that the minimum principal stress axis σ3 are subhorizontal with a predominant N-S orientation. In the SW Peloponnese the orientation of σ3 axes rotates clockwise and in SE Aegean counterclockwise. These results are in agreement with the generally accepted model that slab rollback combined with gravitational spreading of the Aegean lithosphere are the main causes of the extension. Transitions between different faulting types in NW Greece or in the Aegean occur within narrow zones in the order of tens of kilometers. A visual comparison of the principal horizontal stress axes and the principal strain axes derived from GPS observations shows good agreement, suggesting that the crust in the Greek region behaves largely in an elastic manner.

[1] We present a 2.14-Myr astronomically tuned relative geomagnetic paleointensity record from the western Philippine Sea. Pseudosingle-domain titanomagnetite is the only magnetic mineral identified and variations in titanomagnetite concentration fall well within the accepted limits for relative paleointensity variations. No significant temporally persistent periodicities are observed in wavelet analyses of the paleointensity time series or in the rock magnetic parameters used for relative paleointensity normalization. This suggests that our paleointensity record is largely free of rock magnetic or lithological artefacts and that it represents a reliable record of geomagnetic behavior with no evidence for modulation of the field at Earth orbital periods. The paleointensity record is highly coherent with the Sint-800 global paleointensity stack for the last 800 kyr and with a coeval record from the West Caroline Basin. Our record confirms that it is normal for the geomagnetic field to undergo dynamic changes within polarity intervals, with relatively frequent collapses of the field to low paleointensities and concomitant deviations away from the stable field direction. We do not observe an asymmetrical sawtooth form in our paleointensity record, which might suggest that previously observed asymmetrical sawtooth paleointensities result from rock magnetic artefacts. Also, we do not observe a persistent 100-kyr inclination periodicity, in contrast to the suggestion that geomagnetic field directions are modulated by orbital eccentricity. Good agreement between our paleointensity record and the coeval West Caroline Basin record provides the beginning of a detailed view of geomagnetic field behavior between 0.8 and 2.14 Ma.