Constraining a model of punctuated river incision for Quaternary strath terrace formation

In the small fraction of Earth's surface with highest erosion rates such as Alps and Himalayas quantifying incision, rock uplift inferring climatic controls on landscape can be relatively straightforward once ages river terraces cut in bedrock (strath terraces) are constrained. However, many mid to lower relief settings that more typical mountain belts worldwide, periods net incision riverbed lowering short (punctuated), interrupted by long sediment aggradation or stasis. We define a conceptual model punctuated strath terrace formation for calculation rates, recommend strategies geochronological sampling interpretation. An approach using OSL dating gravels allows us constrain detailed ~150 kyr history spanning two stratigraphic landform levels High Atlas Mountains (NW Africa). Extensive preservation exposure strath-top gravels, within post-orogenic setting unaffected eustatic influences, enables derivation base-level fall, integrated over consistent independently constrained regional rates. Combining our well-constrained demonstrate how assumptions concerning Quaternary lead problematic Sadler Effect, an apparent dependence measured time interval. Subsequently, we reinterpreting previously published data model, even when combined limited age data, results conclusions about across belt. Our recommendations require samples taken just above surface, addition towards top deposit formation, both burial dates, exclusive use abandonment will not yield constraints accurate incision. Furthermore, find only multiple along-stream locations dates each deposit, could reliable signal extracted: this would have shown up those derived from cosmogenic dates. The demonstrated effects recommended approaches interpretation, implications attempting palaeoclimatic, tectonic, geomorphic histories records regions exhibiting