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Lithospheric extension during the Miocene is well documented in the Aegean. Within the Central and Western Cyclades extension has been documented in detail by the formation of Metamorphic Core Complexes and movement along low-angle normal faults (LANFs). Focusing on a hitherto unrecognised main low-angled fault geometry outcropping on northern Kea, this work presents pervasive evidence of top-to-south kinematics. [ABSTRACT FROM AUTHOR]

The geology of Kea Island shows further evidence for low-angle normal fault (LANF) formation in the Western Cyclades. Structural investigations have demonstrated the existence of a hitherto unrecognised ductile-brittle shear zone with strikingly consistent top-to-SSW extensional kinematics together with a WNW-ESE oriented shortening component. The tectonostratigraphy comprises a >380 m thick, shallowly-dipping schist-calcite marble unit, overlain by ca. 150 m thick fault rocks consisting of cohesive cataclasites, ultramylonitic calcite marbles, brecciated dolostones and protomylonitic calcite marbles. The presence of blueschist-facies lenses and 40Ar/39Ar geochronology point to a significant role of LANFs in exhumation processes and greenschist-facies overprint during Miocene crustal evolution. [ABSTRACT FROM AUTHOR]

On the island of Serifos SSW-directed low-angle faults accommodated crustal thinning during Miocene extension. Cross-cutting relationships suggest that the low-angle faults interacted with WNW-ESE striking conjugate high-angle normal faults in both the hanging and the footwall. Although high- and low-angle faults were likely synkinematic, the deformation mechanism differs significantly in both systems. The low-angle faults are characterized by several meters of low-grade, ultrafine grained marble mylonites below several decimetres of ultracataclasites. The high-angle faults represent mainly brittle deformation resulting in slickensides, cataclasites and pseudotachylites. The Ar/Ar mica geochronology yields uniform ages across the low-angle faults suggesting a nearly horizontal detachment at temperatures coincident with the brittle-ductile transition zone. [ABSTRACT FROM AUTHOR]

The Khlong Marui Fault, lying to the NNE of Phuket, has a strong geomorphic signal, with marked fault-strike parallel topographic ridges. The fault is ca. 150 km long with a 210-030° trend. The lithologies within the strike-slip zone mainly consist of vertical layers of mylonitic metapelites, migmatitic gneiss, mylonitic granite, pegmatites and cataclasites. The foliation and stretching lineations in ductile rocks indicate a dextral strike-slip displacement at mid- to upper-crustal levels. Pegmatites cross-cut the mylonitic foliation but are in turn sheared at their margins, indicating synkinematic emplacement. Although clear age-constraints are still lacking, the dextral strike-slip kinematics of the Khlong Marui fault is likely to be related to the escape tectonics arising from the India-Asia collision. [ABSTRACT FROM AUTHOR]

Spectacular folded, but virtually unconsolidated sediments in a sand pit in the Vienna basin have been used as one of the key arguments of an E-W shortening event during the Late Miocene in the eastern Alps and western Carpathians. The outcrop has been re-excavated recently and several new observations like the occurrence of refold structures, the fold shapes and the large amount of localized shortening bring into question the established tectonic interpretation. Alternatively, we propose that gravitational forces caused the folding in the frontal part of a slump along the eastern slope of the Vienna basin. [ABSTRACT FROM AUTHOR]

Recent field investigations have revealed a high-strain zone in the south of Kythnos (Greece). Massive layers of ultrafine-grained Mn-rich calcitic mylonitic marbles and several generations of cataclasites hint at a high-strain event in the crust and are associated with a low-angle shear zone. We investigate fold-fault-relationships and deformation events preceding and post-dating normal faulting and compare the tectono-metamorphic history with adjacent islands in the Western Cyclades. [ABSTRACT FROM AUTHOR]

In a gravel pit (SE Vienna basin), metre-thick bedded successions of conglomerate and sand layers of Miocene age are exceptionally well exposed along a W-E-striking wall. The sediments are cut by numerous N-Sstriking, high-angle normal faults. The faults have a marked displacement gradient and offset marker layers of up to several metres. Using ground penetrating radar, we measured ten sections parallel to the W-E-striking wall in order to construct a three-dimensional structural model. Exact positioning of the radargrams was achieved with the help of differential GPS and compilation of the data with a terrestrial laser scan of the outcrop. [ABSTRACT FROM AUTHOR]