Abstract The effect of mean precipitation rate on erosion is debated. Three hypotheses may explain why the current erosion rate and runoff may be spatially uncorrelated: (1) the topography has reached a steady state for which the erosion rate pattern is determined by the uplift rate pattern; (2) the erosion rate only depends weakly on runoff; or (3) the studied catchments are experiencing different transient adjustments to uplift or to climate variations. In the Chilean Andes, between 27°S and 39°S, the mean annual runoff rates increase southwards from 0.01 to 2.6 m a −1 but the catchment averaged rates of decadal erosion (suspended sediment) and millennial erosion ( 10 Be in river sand) peak at c. 0.25 mm a −1 for runoff c. 0.5 m a −1 and then decrease while runoff keeps increasing. Erosion rates increase non-linearly with the slope and weakly with the square root of the runoff. However, sediments trapped in the subduction trench suggest a correlation between the current runoff pattern and erosion over millions of years. The third hypothesis above may explain these different erosion rate patterns; the patterns seem consistent with, although not limited to, a model where the relief and erosion rate have first increased and then decreased in response to a period of uplift, at rates controlled by the mean precipitation rate.

Abstract 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.

Abstract SE Iran is the site of a rare case of young transition between subduction and collision. We have synthesized recent results in geodesy, tectonics, seismology and magnetism to help understand the structure and kinematics of the Zagros–Makran transition. Surface observations (tectonics, magnetism and geodesy) indicate a transpressive discontinuity consisting of several faults striking obliquely to the convergent plate motion, whereas deeper observations (seismology) support a smooth transition across the fault system. No lithospheric transform fault has been created, although the transition already behaves like a major boundary in terms of tectonic style, seismic structure, lithology and magnetism. The Zendan–Minab–Palami fault system consists of several faults that accommodate a transpressive tectonic regime. It is the surface expression of a southward propagation of the north–south-trending right-lateral strike-slip fault system of Jiroft–Sabzevaran. Within each system the numerous faults will coalesce into a single, lithospheric, wrench fault.