Plan-form evolution of drainage basins in response to tectonic changes: Insights from experimental and numerical landscapes

Abstract

Spatial gradients in rock uplift control the relief and slope distribution in uplifted terrains. Relief and slopes, in turn, promote channelization and fluvial incision. Consequently, the geometry of drainage basins is linked to the spatial pattern of uplift. When the uplift pattern changes basin geometry is expected to change via migrating water divides. However, the relations between drainage pattern and changing uplift patterns remain elusive. The current study investigates the plan-view evolution of drainage basins and the reorganization of drainage networks in response to changes in the spatial pattern of uplift, focusing on basin interactions that produce globally observed geometrical scaling relations. We combine landscape evolution experiment and simulations to explore a double-stage scenario: emergence of a fluvial network under block uplift conditions, followed by tilting that forces drainage reorganization. We find that the globally observed basin spacing ratio and Hack's parameters emerge early in basin formation and are maintained by differential basin growth. In response to tilting, main divide migration induces basins' size changes. However, basins' scaling relations are mostly preserved within a narrow range of values, assisted by incorporation and disconnection of basins to and from the migrating main divide. Lastly, owing to similarities in landscape dynamics and response rate to uplift pattern changes between experiment and simulations, we conclude that the stream power incision model can represent fluvial erosion processes operating in experimental settings. Hosted fileagu_suppinfo.docx available at https://authorea.com/users/524177/articles/595409-plan-formevolution-of-drainage-basins-in-response-to-tectonic-changes-insights-from-experimentaland-numerical-landscapes Hosted file essoar.10512204.1.docx available at https://authorea.com/users/524177/articles/595409plan-form-evolution-of-drainage-basins-in-response-to-tectonic-changes-insights-fromexperimental-and-numerical-landscapes 1

Plan‐Form Evolution of Drainage Basins in Response to Tectonic Changes: Insights From Experimental and Numerical Landscapes

“…The raw data used in the analysis of the experiment and simulations referred to in this paper, containing DEMs and MATLAB scripts, can be found in Habousha et al (2022) with the URL: https://zenodo.org/record/6890372#. Y9pmHXbP1D8.…”