I n their Comment on our study (1), Zeitler et al. (2) imply that we interpreted our findings to question the possible existence of feedbacks between surface and tectonic processes, which is not the case. We therefore appreciate the opportunity to clarify potentialmisunderstandings. Zeitler et al. (2) suggest that the oldest sediments at the base of the valley fill could be 3 to 4 million years...
