Search results for "Strike-slip"

Structural overprint of a late Paleozoic accretionary system in north-central Chile (34°-35°S) during post-accretional deformation

2009

En la Cordillera de la Costa de Chile, de 36° a 35°S, se encuentra expuesta la arquitectura coherentemente preservada de un prisma de acrecion del Paleozoico tardio, en cercana vecindad a un area entre los 34° y 35°S, donde el mismo esta fuertemente modificado por procesos postacrecionales. Estudiando las desviaciones de la arquitectura original, en esta region pueden ser perfectamente distinguidas estructuras sin- y post acrecionales. Al sur de los 35° se observa un contacto transicional entre dos unidades mayores, el cual refleja un cambio continuo en el modo de acrecion de la cuna acrecional antes de -305 Ma: las metagrauvacas estructuralmente suprayacentes de las series orientales muest…

Multi-scale properties of strike-slip faults corss-cutting the Pleistocene carbonate grainstones of Favignana Island (NW Sicily, Italy)

2010

The southern Tyrrhenian Sea margin an example of lithospheric scale strike-slip duplex

2010

The southern Tyrrhenian Sea margin is dominated by deformations whose kinematics are relatively poorly constrained, and different models have been proposed to account for its recent evolution. Analysis of new structural and space geodesy data, combined with available geophysical information, reveal a deformation field characterised by subhorizontal NW-SE directed shortening and SW-NE directed extension. The main recognised regional-scale structure comprises E-W trending fault zones, namely the Ustica-Eolie Line and the Mt. Kumeta-Alcantara Line, connected by the NW-SE trending Marettimo, Trapani, San Vito, Palermo, Gratteri-Mt. Mufara and Eolie faults. This fault network displays a remarkab…

Lower Crustal Rheology Controls the Development of Large Offset Strike‐Slip Faults During the Himalayan‐Tibetan Orogeny

2020

International audience

Palaeomagnetism of the central Cuban Cretaceous Arc sequences and geodynamic implications

2009

Abstract A detailed palaeomagnetic study of Cretaceous age volcanic and sedimentary arc rocks from central Cuba has been carried out. Samples from 32 sites (12 localities) were subjected to detailed demagnetisation experiments. Nineteen sites from the Los Paso, Matagua, Provincial and Cabaiguan Formations yielded high unblocking temperature, dual polarity directions of magnetisation which pass the fold tests with confidence levels of 95% or more and are considered to be primary in origin. The palaeomagnetic inclinations are equivalent to palaeolatitudes of 9°N for the Aptian, 18°N for the Albian. A synfolding remanence identified in 5 sites from the younger Hilario Formation indicates a lat…

Normal vs. strike-slip faulting during rift development in East Africa: The Malawi rift

1992

Kinematic analysis of Neogene and Quaternary faults demonstrates that the direction of extension in the Malawi rift rotated from east-northeast to southeast. Rift development commenced with the formation of half-grabens bounded by northwest-, north-, and northeast-striking normal faults. Owing to slightly oblique rifting, the northwest-striking faults in the northernmost rift segment show a small dextral oblique-slip component, whereas north- and northeast-oriented faults in the central part of the rift display a sinistral oblique-slip component. This first event resulted in block faulting and basin subsidence, which is largely responsible for the present-day basin morphology of Lake Malawi…

How to make a transverse triple junction—New evidence for the assemblage of Gondwana along the Kaoko-Damara belts, Namibia

2016

T-shaped orogenic triple junctions between mobile belts usually form in two unrelated stages by subsequent and oblique continental collisions separated by a significant time span. Besides these “oblique triple junctions”, another type, named “transverse triple junctions”, may exist. Such junctions are created by a more complex mechanism of partly contemporaneous convergence of three cratons in a restricted time frame, involving strike slip. The Neoproterozoic–Cambrian Kaoko-Damara junction between the Rio de la Plata, Congo, and Kalahari cratons in Namibia is an example of such a transverse orogenic triple junction, formed by at least four subsequent but partly related deformation events. I…

2020

Abstract. New Zealand's Alpine Fault is a large, plate-bounding strike-slip fault, which ruptures in large (Mw>8) earthquakes. We conducted field and laboratory analyses of fault rocks to assess its fault zone architecture. Results reveal that the Alpine Fault Zone has a complex geometry, comprising an anastomosing network of multiple slip planes that have accommodated different amounts of displacement. This contrasts with the previous perception of the Alpine Fault Zone, which assumes a single principal slip zone accommodated all displacement. This interpretation is supported by results of drilling projects and geophysical investigations. Furthermore, observations presented here show th…

Plio-Pleistocene strike-slip deformation in NE Sicily: the example of the area between Capo Calavà and Capo Tindari

2005

The Peloritani Mts. in Northeastern Sicily are part of the Sicilian orogenic belt interposed between the Tyrrhenian basin and the Ionian Basin. In the Tyrrhenian basin crustal thinning has been active since the late Miocene, whereas wedge accretion (External Calabrian Arc) has occurred in the Ionian basin, due to the north-westward subduction of the Ionian Plate below the Calabrian-Peloritani Arc. Strike-slip tectonics in NE Sicily occurred during Plio-Pleistocene times. Faulting caused a non-uniform uplift rate of the Plio-Pleistocene deposits, which are elevated up to 500 m above sea level. The structural pattern is mainly represented by NW-SE and N-S/NNE-SSW trending transcurrent faults …