Field migration rates of tidal meanders recapitulate fluvial morphodynamics

Area of Science:

• Earth and Planetary Sciences
• Geomorphology
• Sedimentology

Background:

• Tidal channels often exhibit significant meandering patterns, crucial for oil reservoir formation and coastal morphology.
• Conventional understanding posits tidal meanders as stable features, unlike their migrating fluvial counterparts, due to reversed flow dynamics.

Purpose of the Study:

• To investigate whether tidal meander dynamics can be explained by fluvial processes and theories.
• To challenge the established view of tidal channels as static landscape elements.

Main Methods:

• Normalization of tidal and fluvial meander migration rates using tidal channel width.
• Analysis of spatial gradients in landscape-forming flow rates and tidal prisms.
• Comparison of normalized tidal meander migration with nonlinear theories of river meander evolution.

Main Results:

• Normalized migration rates of tidal and fluvial meanders show remarkable similarity.
• Tidal channel width is identified as a key factor for normalization, influenced by flow rate and tidal prism gradients.
• Tidal meander migration dynamics are consistent with nonlinear theories of river meander evolution.

Conclusions:

• The study challenges the notion of stable tidal channels, demonstrating their dynamic, migrating nature.
• Meandering tidal channels share significant similarities with fluvial counterparts, driven by tidal prism gradients.
• Fluvial meander theories can be applied to understand tidal meander evolution.