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The crest of the Andes--the trace of the highest mountain topography--weaves back and forth, in places near the coastline, in others farther inland. Its position reflects the asymmetric distribution of orogen mass and coincides with asymmetry of orographic precipitation. This coincidence is thought to reflect a primary influence of orographic precipitation on accumulated orogenic mass whereby the more erosive (wetter) side promotes crest migration toward the less erosive (drier) side. However, whether this remains the case after excluding tectonic controls on the size and asymmetry of the wedge is an open question. We assessed relationships between precipitation, erosion rates, and the macromorphology of the Andes. We find that precipitation rates cannot sufficiently explain orogen asymmetry after statistically controlling for the age or dip of the Nazca slab. Slab age and dip are known to primarily affect mountain building in the Andes by impacting stress and strain propagation into the retro-arc region, thus better explaining the position of the mountain chain within the orogenic wedge. Accordingly, using basin-wide erosion rate, topographic, and precipitation data, we find that precipitation possibly influences erosional efficiency in semi-arid Andean landscapes but falls short in explaining the variability of erosion rates in regions of high orographic precipitation. We conclude that the orographic effect cannot change the Andean macromorphology that is set by bottom-up tectonic processes. [ABSTRACT FROM AUTHOR]

A correction is presented to the article "Across-strike asymmetry of the Andes orogen linked to the age and geometry of the Nazca plate."