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A B S TR A CT The Moldanubian zone in Austria comprises three major lithological units. Despite general agreement that nappe tectonics contributed to its current structure, the number and position of tectonic boundaries, or continental pieces that were involved in its evolution, as well as the age, extent and position of oceanic sutures are disputed. Recent models ascribe the Moldanubian tectonostratigraphic structure to its oblique, N-to NE-directed collision with Moravia only.The rocks of the Moldanubian Bunte series and Gfö hl unit experienced a common, intensive overprint in the range 700-800°C and 8-11 kbar. Textural evidence suggests that this overprint was attained during nearly isothermal decompression, so the rocks experienced higher pressures prior to this overprint. These conditions constrain a continent-continent collision environment that contributed to the formation of the Moldanubian granulites. The estimated metamorphic temperatures are close to T max . During this Hercynian, high-T overprint, the minerals underwent extensive diffusion-controlled homogenization of elements. The early stages of retrogression of these units were characterized by isobaric cooling at c. 6 kbar in the range 650-500°C that is related to the oblique collision of the Moldanubian and Moravian zones. Cooling to c. 400°C is demonstrated by unstrained, diasporized corundum inclusions in garnet of common Moldanubian granulites.The available age data (including cooling ages) from metamorphic rocks show a very wide variation between 490 and 280 Ma that depends on sample characteristics and the dating method used. They demonstrate clearly, however, that the metamorphic overprint is Hercynian. The possibility that the large variation in ages reflects homogenization, resetting and closure of the isotopic systems attained at different, sample-and method-specific times is discussed. Age data varying between c. 370 and c. 346 Ma tentatively date different stages during the Hercynian, high-T decompression. The majority of zircon and monazite U/Pb ages as well as the hornblende and muscovite Ar/Ar cooling ages cluster between c. 345 and c. 326 Ma and date the effective closure conditions and the onset of rapid, nearly isobaric cooling. The continentcontinent collision that formed the granulites pre-dates c. 370 Ma. The intra-Moldanubian nappe-stacking pre-dates thrusting of the Moldanubian zone over the Moravian zone. The range c. 340-335 Ma is the lower limit for completion of tectonic activity in the Moldanubian zone.The Moldanubian series are post-tectonically intruded by granitoids of the Southern Bohemian Pluton. Recent age determinations and geochemical evidence suggest that the formation of the early granitoid types took place in the lower crust in connection with the Hercynian high-grade overprint.The Moldanubian Monotone series in Austria is separated from the other Moldanubian units by a conspicuous tectonic horizon. It also differs from them by its characteristic high-T , low-P overprint, which is best demonstrated by a wides...

[1] New structural, petrologic, and thermochronologic data from Kea, West Cyclades, define a crustal-scale ductile shear zone and ductile/brittle low-angle normal fault (LANF) system. Both the greenschist-facies shear zone forming the footwall and the overlying LANF zone formed during constrictional strains, with a consistent top-to-SW-S shear sense, with increasing finite strains toward higher structural levels but decreasing temperatures from footwall to hanging wall. The tectonostratigraphy comprises a ∼450 m thick footwall of shallowly dipping schists and calcite marbles representing the Intermediate Unit of the Attic-Cycladic Crystalline (ACC). Above the footwall is a ∼60 m thick highly strained LANF zone, consisting of phyllonites, cataclastic schists, ultramylonitic calcite marbles, (proto) mylonitic calcite marbles, and cohesive cataclasites that arch over the whole island. These fault rocks exhibit multistage LANFs, evolving from ductile to brittle conditions. An up to ∼50 m thick brecciated limestone and dolostone sequence forms the unmetamorphosed hanging wall which is most probably part of the Upper Unit of the ACC. Multiequilibrium P-T estimates on chlorite-white mica pairs in the footwall yield 7-5.5 kbar/360°C-450°C for inclusions in albite and epidote, 5.5-3 kbar/400°C-350°C for the main foliation, and 3-2 kbar/350°C-280°C in localized shear bands (C and C′ foliations). The 40 Ar/ 39 Ar white mica footwall cooling ages demonstrate that greenschist-facies retrogression occurred between ∼21 and 17 Ma. Localized, late decimeter thick shear zones were active and dynamically recrystallized before ∼15 to 13 Ma. The LANF on Kea, together with similar structures in South Attica and the West Cyclades define the West Cycladic Detachment System, characterized by ductile to brittle top-SW-S shear sense.