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Cari koleksi dengan cepat sesuai kebutuhan Anda.Several large earthquakes in the Hellenic subduction zone have been documented in historical records from around the eastern Mediterranean, but the relative seismic quiescence of the region over the period of instrumental observation means that the exact locations of these earthquakes and their tectonic significance are not known.We present AMS radiocarbon dates from uplifted late Holocene pal�…
Progressive deformation of upper mantle rocks via dislocation creep causes their constituent crystals to take on a non-random orientation distribution (crystallographic preferred orientation or CPO) whose observable signatures include shear-wave splitting and azimuthal dependence of surface wave speeds. Comparison of these signatures with mantle flow models thus allows mantle dynamics to be unr…
The intra-plate deformation of the Upper Rhine Graben (URG) located in Central Europe is investigated using geodetic measurement techniques. We present a new approach to calculate a combined velocity field from InSAR, levelling and GNSS measurements. As the expected tectonic movements in the URG area are small (less than 1mma−1), the best possible solutions for linear velocity rates from …
The Piton de la Fournaise basaltic volcano, on La R´eunion Island in the western Indian Ocean, is one of the most active volcanoes in the world. This volcano is classically considered as the surface expression of an upwelling mantle plume and its activity is continuously monitored, providing detailed information on its superficial dynamics and on the edifice structure. Deeper crustal and uppe…
Magnetic minerals acquire a remanent magnetization when cooled or warmed in an applied field H through a phase transition. This paper reports the first observations of transition cooling and warming remanent magnetizations (TrCRM and TrWRM) in pyrrhotite (Fe7S8) and hematite (αFe2O3), with phase transitions at 32 K (Besnus transition) and 250 K (Morin transition). TrWRM was produced by wa…
Reconstructions of the history of convergence between the Nubia and Eurasia plates constitute an important part of a broader framework for understanding deformation in the Mediterranean region and the closing of the Mediterranean Basin. Herein, we combine high-resolution reconstructions of Eurasia-North America and Nubia-North America Plate motions to determine rotations that describe Nubia-Eur…
The Rogaland Igneous Complex (RIC) in southern Norway intruded into post-Sveconorwegian granulite facies crust ∼930 Ma. It includes three massif anorthosites, several small leuconorite bodies and the ∼7 km thick norite-quartz mangerite layered Bjerkreim-Sokndal (BKS) intrusion. The intrusion consists of five rhythmic megaunits created by repeated magma influxes topped by a transitio…
The dispersion of interface waves is studied theoretically in a model consisting of a liquid layer of finite thickness overlying a transversely isotropic solid layer which is itself underlain by a transversely isotropic solid of dissimilar elastic properties. The method of potential functions and Hankel transformation was utilized to solve the equations of motion. Two frequency equations were …
We study the well log and seismic responses of intensively fractured portions of deep intrusive/metamorphic rocks in southern Tuscany (Italy), which constitute the main drilling targets of the geothermal exploration in the Larderello–Travale area. In particular, the target we consider is located near the contact between a deep Pliocene granitic intrusion and the overlying Palaeozoic metamorph…
We show a case study of full-waveform inversion (FWI) applied to a regional 240-km long seismic profile (called POLCRUST-01) located in southeast Poland. The experiment is unique because it portrays different tectonic deformation styles over a relatively short distance. It was designed for deep reflection imaging, but we decided to use FWI to provide a high-resolution P-wave velocity model of t…