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International audience; The Corinth rift (Greece) is an exceptional area to study the large-scale mechanics of a young rift system due to its extremely high extension rates and fault slip rates. Middle-Late Pleistocene activity of large normal faults has created a mostly asymmetric E-W trending rift, mainly driven by N-dipping faults that shape the southern margin of the Corinth Gulf in an en echelon pattern. We improve the onshore record of footwall uplift by analysing the most extensive sequence of marine terraces in the SE margin, combine this dataset with the offshore seismic record of hanging wall subsidence, and present simple numerical models to fit the observations.

International audience; The subduction of bathymetric anomalies at convergent margins can profoundly affect subduction dynamics, magmatism, and the structural and geomorphic evolution of the overriding plate. The Northern Patagonian Icefield (NPI) is located east of the Chile Triple Junction at ~47°S, where the Chile Rise spreading center collides with South America. This region is characterized by an abrupt increase in summit elevations and relief that has been controversially debated in the context of geodynamic versus glacial erosion effects on topography. Here we present geomorphic, thermochronological, and structural data that document neotectonic activity along hitherto unrecognized faults along the flanks of the NPI. New apatite (U-Th)/He bedrock cooling ages suggest faulting since 2–3 Ma. We infer the northward translation of an ~140 km long fore-arc sliver—the NPI block—results from enhanced partitioning of oblique plate convergence due to the closely spaced collision of three successive segments of the Chile Rise. In this model, greater uplift occurs in the hanging wall of the Exploradores thrust at the northern leading edge of the NPI block, whereas the Cachet and Liquiñe-Ofqui dextral faults decouple the NPI block along its eastern and western flanks, respectively. Localized extension possibly occurs at its southern trailing edge along normal faults associated with margin-parallel extension, tectonic subsidence, and lower elevations along the Andean crest line. Our neotectonic model provides a novel explanation for the abrupt topographic variations inland of the Chile Triple Junction and emphasizes the fundamental effects of local tectonics on exhumation and topographic patterns in this glaciated landscape.

International audience; The great variety of climatic conditions, tidal ranges and wave regimes of South and Central America act on a complex geology and tectonic framework. Many of the rock and cliffed coasts of South America are strongly controlled by the occurrence of extensive Cenozoic and Pleistocene sediments that crop out at the coast. Geology and the different uplift rates are a major factor in the whole coastal geomorphology of South and Central America, and consequently are a very important control of the processes and landforms of rock coasts. This chapter covers several aspects of the rock coast of South and Central America, with special attention to the combination of tectonic movements and Quaternary Pleistocene– Holocene sea-level changes.

The great variety of climatic conditions, tidal ranges and wave regimes of South and Central America act on a complex geology and tectonic framework. Many of the rock and cliffed coasts of South America are strongly controlled by the occurrence of extensive Cenozoic and Pleistocene sediments that crop out at the coast. Geology and the different uplift rates are a major factor in the whole coastal geomorphology of South and Central America, and consequently are a very important control of the processes and landforms of rock coasts. This chapter covers several aspects of the rock coast of South and Central America, with special attention to the combination of tectonic movements and Quaternary Pleistocene–Holocene sea-level changes.

Reversible cryothermal mapping of cardiac arrhythmias has beenperformed intraoperatively. However, a steerable cooling catheter forreversible mapping has not yet been developed. We therefore developed andtested a cooling system consisting of a +15°C hypertonic salinereservoir and a 7F steerable catheter also capable of radiofrequency (RF)ablation. Using excised ovine hearts placed in a 37°C circulating salinebath, we measured the temperatures at depths of 0 mm, 1 mm, and 2 mm. Thetemperature after 90 seconds of cooling was 16.5 ± 2.1°C at 0 mmcompared to 23.9 ± 4.1°C at 1 mm and 31.1 ± 3.9°C at 2mm depth (p < 0.01). These data suggest that a 7F steerable combined RFablation–cooling catheter may achieve temperatures suitable formapping arrhythmias such as atrial tachycardias and right ventricularoutflow tract tachycardias. Further enhancements to achieve lowertemperatures at depth may be needed to reversibly map other arrhythmiassuch as left ventricular tachycardias.

The Maule earthquake of 27th February 2010 (Mw=8.8) affected about 500 km of the Nazca-South America plate boundary in south-central Chile producing spectacular crustal deformation. This earthquake occurred on a mature seismic gap, which presented a high degree of plate locking in the decade preceding the event. Shaking, tsunami inundation and coastal uplift patterns show similarities with its predecessor in 1825, suggesting that both events ruptured an analogous segment of the plate boundary. Here, we present estimates of static coseismic surface displacements measured by a dense GPS network and used them in conjunction with published geodetic data to obtain an updated, higher-resolution slip model of the 2010 Maule earthquake. The use of a finite element model that introduced the main geometrical complexities of the Chile subduction zone allowed us to compare the spatial relation of slip patterns before and during the 2010 Maule earthquake with tectonic features of the forearc. The combination of the data sets provided a good resolution, indicating that most of the slip was well resolved. Coseismic slip was concentrated north of the epicenter with up to 16 m of slip, whereas to the south it reached over 10 m within two minor patches. The theoretical accumulated slip deficit including the 1960 earthquake slip that overlapped 150 km of the 2010 rupture; the 1928 and 1985 events; as well as heterogeneous plate locking suggests that the 2010 event closed the seismic gap. Slip deficit distribution shows an apparent local overshoot that highlight cycle-to-cycle variability, which has to be taken into account when anticipating future events from interseismic observations. Rupture propagation was obviously not affected by bathymetric features of the incoming plate. Instead, splay faults in the upper plate seem to have limited rupture propagation in the updip and along- strike directions. Additionally, we found that along-strike gradients in slip are spatially correlated with geometrical inflections of the megathrust. Our study suggests that persistent tectonic features may control strain accumulation and release along subduction megathrusts inducing a seismotectonic segmentation persistent over several seismic cycles.

The northern margin of the Central Anatolian Plateau spans the northward arched part of the Pontide Mountains between the North Anatolian Fault to the south and the Black Sea to the north. Crustal deformation between the North Anatolian Fault and the Black Sea is integrally tied to the evolution of the Central Anatolian Plateau. The asymmetric topographic pattern, coupled with the spatial distribution and geometry of faults, suggest that the northern margin of the plateau has constituted an active accretionary orogenic wedge with northward polarity between the North Anatolian Fault and the abyssal plain of the Black Sea (Figure). To explore the mode and rate of rock uplift that is associated with internal deformation in the accretionary orogenic wedge, we dated incised and deformed pediments by measuring in situ produced 10Be, 21Ne and 36Cl concentrations. The key target area for our analysis is the Kastamonu intramontane basin. We mapped a suite of six gravel-covered pediment surfaces in the basin that rise 175-180m (P1), 115-130 m (P2), 70-80 m (P3), 45-54 m (P4), 25-35 m (P5) and 12-22 m (P6) above the river. One set of samples was collected along the trunk stream of the Kastamonu basin to estimate trunk stream incision rates, and a second set of samples was collected from local surfaces that have been deformed and incised in response to faulting in the accreationary orogenic wedge. The surfaces within the basin have exposure ages that range from about. (7.8±0.9) ka to (437 ±64) ka. The temporal distribution of the abandonment ages suggests that specific climatic conditions do not promote abandonment of pediment surfaces in the Kastamonu Basin. The abandonment ages and strath heights of the surfaces yield incision rates that range from 0.20 to 0.49 mm/yr along the trunk stream of the Kastamonu Basin. We used an average fluvial incision rate to calculate rock uplift rate, i.e., incision between the 70-80 m (P2) and 12-22 m (P6) pediments along the trunk stream of the Kastamonu Basin. This gives ~0.27 mm/yr of average vertical rock uplift rate between ca. 437 and 22 ka in the internal part of the Central Pontides. The highest incision rates (1.04 to 3.16 mm/yr) in the basin are obtained from local surfaces deformed by faults along the basin margins. Topographic profiles across the local pediment surfaces show discernable warping in evidence of out of sequence faulting and partial accommodation of internal deformation in the orogenic wedge. We believe that out-of-sequence faulting and internal deformation indicate a subcritical state of the orogenic wedge at the northern margin of the Central Anatolian Plateau.

The M8.8 Maule earthquake of 27 Feb. 2010 in Chile was the largest earthquake that ruptured a mature seismic gap in a subduction zone, monitored with a dense space-geodetic network. This provides an image of the pre-seismically locked state of the plate interface of unprecedented high resolution, allowing for an assessment of the spatial correlation of interseismic locking and coseismic slip. Here we use GPS observations spanning the decade preceding the 2010 Maule earthquake to derive the pre-seismically surface deformation. Additionally, we use static coseismic surface displacements of 42 campaign GPS sites, InSAR data and land level changes to constrain the co-seismic slip distribution. Inter- and coseismic surface velocities are modeled using a spherical and layered finite element model (FEM) of the Andean subduction zone, including topography, bathymetry and realistic plate configurations as compiled from recent geophysical transects. According to our analysis, the 2010 Maule earthquake ruptured a part of the plate margin that was accumulating stresses across a heterogeneously locked interface in the final few years of an earthquake cycle. Despite differences in resolution and complexity, our and published slip distributions show a first-order pattern of two high-slip patches (asperities) north and south of the epicenter and separated by a low-slip zone 50-100 km wide. The rupture stopped in areas that were highly locked before the earthquake but where pre-stress had been significantly reduced by overlapping twentieth-century earthquakes. The largest recorded coastal uplift of up to 2 m occurred in the Arauco Peninsula, with peak horizontal displacements of 5 m at the Santa María Island. In the preliminary slip model presented we relate this uplift to elastic deformation caused by an asperity with slip of up to ~8 m in the southernmost part of the rupture. This slip component has not been seen by teleseismic models published so far presumably because of the network configuration, low slip velocities, simplified fault geometry, or bilateral propagation of the rupture. Inspection of the similarity between coseismic slip distributions and the pre-seismic locking reveals a high degree of coherence: The two asperities which ruptured in 2010 appeared to have been nearly fully locked before the earthquake. Between these asperities, the rupture bridged the zone that was not fully locked with consistent low coseismic slip. Based on the delicate balance between the 2010 coseismic slip and theoretically accumulated slip deficit since 1835 (which can be calculated under the assumption that the pre-seismic locking pattern is representative of the entire interseismic period) it appears that the observed locking pattern has been temporally largely invariant over the seismic cycle. Our observation suggests that coseismic slip heterogeneity at the scale of single asperities, and therefore the seismic potential of future great earthquakes, can be anticipated by foregoing geodetic observations.