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Abstract

The geomorphologic evolution of orogens has been a subject of revived interest and accelerated development over the past few decades, thanks to both the increasing availability of high-resolution data and computing power and the realisation that orogenic topography plays a central role in coupling deep-earth and surface processes. Low-temperature thermochronology takes a central place in this revived interest, as it allows us to link quantitative geomorphology to the spatial and temporal patterns of exhumation. In particular, rock cooling rates over million-year timescales derived from thermochronological data have been used to reconstruct rock exhumation histories, to detect km-scale relief changes, and to document lateral shifts in relief. In this chapter, we review how classic approaches of determining exhumation histories have contributed to our understanding of landscape evolution, and we highlight novel approaches to quantifying relief changes that have been developed over the last decade. We discuss how patterns of exhumation in laterally accreting orogens are recorded by low-temperature thermochronology, and how such data can be applied to infer temporal variations in exhumation rates, providing indirect constraints on topographic development. We subsequently review recent studies aimed at quantifying relief development and modification associated with river incision, glacial modifications of landscapes, and shifts in the position of range divides. We also point out how interpretations of some datasets are non-unique, emphasizing the importance of understanding the full range of processes that may influence landscape morphology and how each may affect spatial patterns of thermochronologic ages.