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The Kallintiri area (SW Byala Reka–Kechros Dome, Rhodope) hosts a polymetallic (critical, base, and precious metals) ore deposit, tectonically controlled by the late Eocene–Oligocene, top-to-SW Kallintiri Detachment System. The earliest structure associated with the Kallintiri Detachment is a ductile shear zone at the interface between the high-grade footwall gneisses of the Lower and Intermediate Rhodope Terranes. The detachment zone encompasses the uppermost part of the gneisses and the ultramylonitic Makri Unit marble. The marble is bound by a brittle–ductile shear zone at the base and a knife-sharp, low-angle normal fault at the roof, exhibiting considerable brecciation and ultracataclasite development. The hanging wall includes the Makri Unit phyllites and the overlying mid–late-Eocene–Oligocene supra-detachment sediments, which show syn-depositional slump structures and brittle deformation with low- and high-angle faulting and non-cohesive cataclasites. Extensive hydrothermal fluid circulation along the detachment zone and through NW tension gashes and high-angle faults led to pronounced silicification and ore deposition. Field observations and mineralogical and geochemical analyses revealed two primary types of ore mineralization spatially and temporally associated with different structures. Base and precious metals-rich ores are associated with the detachment, while Sb ore deposition is localized mostly within the NW-trending tension gashes and high-angle faults. [ABSTRACT FROM AUTHOR]

Tectonic and lithological correlations between the Cycladic Blueschist Unit of the Aegean domain and Pelagonian domain of the western Turkey have rarely been proposed. Herein, we focus on the pre‐volcanic geology of Kos, and investigate the tectonic history of the central Dodecanese Islands and the general correlation between the two domains. Raman Spectroscopy of Carbonaceous Material analyses combined with white mica 40Ar/39Ar and zircon (U‐Th)/He geochronology were carried out to determine peak temperatures and the timing of tectonothermal events recorded by the various units. Three tectonic units were identified: (a) the Dikeos Unit including the Paleozoic Unit overlain by the Permo‐Triassic Wildflysch Unit, whose rocks have reached a maximum temperature of 300°C; (b) the Marina Basement Unit was thrusted onto the Dikeos Unit with top‐to‐N kinematics during the Paleocene, reaching a maximum temperature of 565°C; (c) the Marina Cover Unit is preserved as isolated klippen juxtaposed onto the Dikeos Unit along the Oligocene top‐to‐SSE Kos Detachment. The Dikeos Unit was then intruded by a c. 10 Ma monzonite, creating a few hundred meters wide metamorphic aureole. At the regional scale, we propose that units from Kos belong to the Pelagonian domain and that post‐orogenic N‐S bivergent extension started in the Oligocene. Over the same time, the deformation started to propagate to deeper structural levels affecting the rocks of the Cycladic Blueschist Unit. Unfortunately, the lack of consensus on the deformation history in southwestern Turkey does not unequivocally allow the constraints to be extended eastward. Finally, mid‐Neogene to recent extension continues within a consistent N‐S direction, which is related to slab retreat and tearing. Key Points: All units from Kos belong to the Pelagonian domainPost‐orogenic N‐S bivergent extension started in the Oligocene in the Pelagonian domainMid‐Neogene to recent extension related to slab retreat and tearing maintains a constant N‐S direction [ABSTRACT FROM AUTHOR]

This manuscript presents a multidisciplinary study that proposes a methodology for delineating and categorizing vulnerability at rockfall risk areas to avoid human injuries and infrastructure damage caused by rockfalls. The presented workflow includes (i) classical geological mapping, (ii) the interpretation of high-resolution satellite data for observing the spatial distribution of fallen boulders, (iii) analytical hierarchy processing of spatial information within a Geographical Information System (GIS) platform, (iv) close-range remote sensing campaigns with Unmanned Aerial Systems (UASs), and (v) integrated simulation of rockfall events. This methodology was applied to Kalymnos Island, which belongs to the Dodecanese Islands complex of the southeastern Aegean Sea in Greece. It is characterized by unique geomorphological features, including extensive vertical limestone cliffs that span the island. These cliffs make it one of the world's most densely concentrated areas for sport climbing. The results highlighted the areas that the local authorities need to focus on and suggested measures for increasing the safety of climbers and infrastructure. [ABSTRACT FROM AUTHOR]

The main purpose of this study is the subsurface investigation of two complex geological environments focusing on the improvement of data acquisition and processing parameters regarding electric and seismic tomographic techniques. Two different study areas, in central–east Peloponnese and SE Attica, were selected, where detailed geological mapping and surface geophysical survey were carried out. The applied geophysical survey included the application of electrical resistivity tomography (ERT), seismic refraction tomography (SRT) and ground penetrating radar (GPR). The geoelectrical measurements were acquired with different arrays and electrode configurations. Moreover, various types of seismic sources were used at seventeen shot locations along the seismic arrays. For the processing of geoelectrical data, clustered datasets were created, increasing the depth of investigation and discriminatory capability. The seismic data processing included the following: (a) the creation of synthetic models and seismic records to determine the effectiveness and capabilities of the technique, (b) spectral analysis of the seismic records to determine the optimal seismic source type and (c) inversion of the field data to create representative subsurface velocity models. The results of the two techniques successfully delineated the complex subsurface structure that characterizes these two geological environments. The application of the ERT combined with the SRT are the two dominant, high-resolution techniques for the elucidation of complex subsurface structures. [ABSTRACT FROM AUTHOR]

Miocene extension in the back arc of the retreating Hellenic subduction zone resulted in metamorphic core complex formation and exhumation of the Cycladic HP‐LT rocks. The extension was accommodated by bivergent detachment systems, generally occupying the interface between the Cycladic Blueschist Unit (CBU) and overlying Pelagonian units. However, the nature and kinematic history of the contact between the CBU and underlying Cycladic Basement (CB) in the southern Cyclades remains debated due to the presence of both top‐to‐the‐N and top‐to‐the‐S kinematics and ambiguities dating the final exhumation stages. Zircon and apatite (U‐Th)/He data and thermal modelling for the CB and CBU on Ios and Sikinos show that both units were likely exhumed as a coherent footwall block in response to rapid slip along the bivergent Miocene Santorini and Naxos‐Paros detachment systems. [ABSTRACT FROM AUTHOR]