Surface Uplift Due To Time‐Varying Elastic Thickness in Continental Interiors

Abstract

Abstract If, as previously hypothesized, the effective elastic response of the lithosphere is sensitive to the imposed stress regime, then it may vary in time and produce distinctive geomorphic responses. Such effects will be at their most crucial in landscapes of low relief. Motivated by the existence of numerous small endorheic (internally‐drained) basins in central Australia, we examine the influence of changing elastic response in the presence of large embedded loads in the lithosphere underlying stable continental interiors. Focusing on the western Lake Eyre Basin and adjoining Lake Lewis basin—an area with a close correlation between drainage pattern and extreme Bouguer gravity anomalies—we devise a set of numerical simulations that incorporate the flexural response to time‐transient horizontal stresses. The simulations demonstrate that transient changes in the effective elastic thickness can drive topographic changes in low‐relief landscapes, including drainage capture and the development of endorheic basins, consistent with field observations.

Keywords

• elastic thickness
• horizontal stress
• Bouguer gravity
• topographic indices
• endorheic basin
• drainage divide