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The South Polar Terrain (SPT) of Enceladus is a site with eruptions of gas and water ice particle plumes, which indicate internal geodynamic activity. These eruptions are located along a series of tectonic structures, that is, the Tiger Stripe Fractures (TSF), which are composed of regularly spaced, linear depressions. The SPT is surrounded by sinuous chains of ridges and troughs (the Marginal Zone). To unravel the tectonics that affect the region and its evolution, we performed specific structural mapping and quantitative analyses of brittle features from remotely sensed images. The results are consistent with a block rotation model, in which several tectonic regimes coexist. The TSF are left‐lateral strike‐slip faults that bound rigid elongated blocks. The blocks rotate clockwise and are enclosed in a regional scale right‐lateral kinematic framework expressed in the Marginal Zone. These two opposite and complementary kinematic regimes induce transtensional and transpressional regimes within the SPT. An evolutionary tectonic model is proposed for the past and future evolution of the SPT. This model confirms the role of tectonic‐related kinematics in icy satellites and contributes to preparations for future missions. Plain Language Summary: The South Pole of Enceladus is one of the most tectonically active regions in the outer solar system. It presents morphotectonic structures that play a key role in the investigation of the internal processes responsible for its crustal deformation and represent possible interaction with the subsurface ocean. In this contribution, we investigate the Enceladus South Polar Terrain (SPT) structures that are mainly represented by the Tiger Stripe Fractures. Their tectonic setting and kinematics are the object of the present study. The results obtained allow inference of block rotation tectonics induced by regional strike‐slip kinematics in the SPT. We propose an evolutionary tectonic model that presents past and future arrangements of the SPT. New findings have allowed identification of a significant compressional component within the study area, as well as the kinematics within this terrain. Key Points: Tectonic activity at Enceladus' south pole is consistent with clockwise block rotation tectonicsRegional right‐lateral strike‐slip kinematics induces transtensional and transpressional regimes in the south polar regionAn evolutionary tectonic model is proposed for the past, present and future settings of Enceladus' south polar structures [ABSTRACT FROM AUTHOR]

A better understanding of intraplate deformation requires the knowledge of the space–time scales involved in its development and to decipher possible links with the dynamic evolution of the plate boundaries. Central Iran provides an ideal test site to approach this scientific issue, since it is characterised by a prolonged history of Mesozoic–Cenozoic intraplate deformation that has been interfering with the spatio‐temporal re‐organization of the Zagros convergence zone along the Eurasia plate boundary. This study focus on the Doruneh Fault (DF) region that is considered as the northern mechanical boundary of the Central East Iranian Microcontinent. By combining field investigations with apatite low‐temperature thermochronology, we present a revised tectono‐stratigraphic scenario for the DF region, typified by a punctuated history of fault‐related exhumation, burial and cooling history back to the Upper Cretaceous. When framed at regional scale, these results attest that the Zagros convergence zone, and its hinterland domain were fully mechanically coupled since ca. 40–35 Ma, a time lapse that is here referred as to the onset of continental collision along the Arabia–Eurasia plate boundary. In this scenario, the DF region operated throughout the Cenozoic as a major zone of residual stress accommodation and transfer in the hinterland domain of the Zagros convergence zone. Results of this study also suggest that the tectonic evolution along the Arabia–Eurasia plate boundary was modulated by the plate‐boundary dynamics and by the modes of tectonic reactivation of the intracontinental weak zones of Central Iran and at its tectonic boundaries. [ABSTRACT FROM AUTHOR]

Abstract: The Cenozoic deformation history of Central Iran has been dominantly accommodated by the activation of major intracontinental strike‐slip fault zones, developed in the hinterland domain of the Arabia‐Eurasia convergent margin. Few quantitative temporal and kinematic constraints are available from these strike‐slip deformation zones, hampering a full assessment of the style and timing of intraplate deformation in Iran and the understanding of the possible linkage to the tectonic reorganization of the Zagros collisional zone. This study focuses on the region to the north of the active trace of the sinistral Doruneh Fault. By combing structural and low‐temperature apatite fission track (AFT) and (U‐Th)/He (AHe) thermochronology investigations, we provide new kinematic and temporal constraints to the deformation history of Central Iran. Our results document a post‐Eocene polyphase tectonic evolution dominated by dextral strike‐slip tectonics, whose activity is constrained since the early Miocene in response to an early, NW‐SE oriented paleo‐σ1 direction. A major phase of enhanced cooling/exhumation is constrained at the Miocene/Pliocene boundary, caused by a switch of the maximum paleo‐σ1 direction to N‐S. When integrated into the regional scenario, these data are framed into a new tectonic reconstruction for the Miocene‐Quaternary time lapse, where strike‐slip deformation in the intracontinental domain of Central Iran is interpreted as guided by the reorganization of the Zagros collisional zone in the transition from an immature to a mature stage of continental collision. [ABSTRACT FROM AUTHOR]

A fundamental yet still unresolved puzzle provided by cataclasis is whether particle size reduction mostly progresses through time by the same fragmentation mechanism or not. Available field, laboratory and numerical modelling results on the evolution of cataclastic rocks are still controversial. The evidence that cataclastic rocks exert a primary control on the frictional strength, stability, seismic velocity and permeability properties of fault zones encourages further research on cataclasis. Here, we report data on particle shape from natural cataclastic rocks in poorly layered carbonates in the Apulian foreland of the Southern Apennines of Italy. Particle shape analyses show that particle angularity decreases with increasing size and, for a given size class, it decreases with increasing fractal dimension of the particle size distribution. These results offer support to the temporally and spatially variable nature of rock comminution. [ABSTRACT FROM AUTHOR]

ABSTRACT Laboratory experiments on rock faulting show that processes of particle comminution in fault rocks are influenced by several parameters, including fault strike and normal stress across faults. In nature, normal stress across faults increases with increasing transpressional strike of faults. Accordingly, different structural fabrics and particle size distributions are expected for cataclastic rocks that have developed along faults with different transpressional orientations and comparable displacements within regional-scale strike-slip fault zones. Adjacent bands of cataclastic gouge and breccia were analysed from four small-scale fault zones. All have comparable displacements and very similar protolith (i.e. shallow-water limestone), structure, kinematics, size, and tectonic environment, but different transpressional strikes within the regional-scale left-lateral Mattinata strike-slip fault, Italy. An inverse linear relationship is found between fault transpressional angles and fractal dimensions of particle size distributions from cataclastic rock samples. [ABSTRACT FROM AUTHOR]

Presents information on a study which traced the evolution of doubly-vergent thrust wedges. Mechanisms for the energy budget of orogens; Role of surface processes in the evolution of the natural thrust system; Main sequences of thrust propagation; Growth of a model doubly-vergent thrust wedge; Conclusions.

Abstract: In the contemporary neoliberal urban dynamics, those agencies that are on the margin of society constantly disrupt the boundaries of civil representation and forge new institutional relations within the dynamics of urban governance. I explore how this process was enacted at the turn of the century in Barcelona, looking at two coeval social mobilisations: the lock‐in of undocumented migrants in the Iglesia del Pi (2001), and the project of las agencias at the Museum of Contemporary Arts (1999–2003), both of which unfolded in the central neighbourhood of Raval. The invasion of the boundaries of civil society emerges here as a double phenomenon—one that develops both within society and in relation to institutions, instituting new modes of urban politics. [ABSTRACT FROM AUTHOR]