Sediment dynamics in a complex coastal lagoon system of the Gulf of California

Abstract

Intense transport of sediments occurs along the eastern coast of the Gulf of California, interacting with several coastal lagoons like Santa María-La Reforma. This sediment dynamics plays an important role in the conservation issue of marine species. The effect of tidal currents on the bed load sediment transport has been investigated for this lagoon, emphasizing the mechanisms of the geomorphologic development of the sea bottom. The flow dynamics has been studied applying the vertically integrated shallow water equations through a modified two dimensional non-linear finite difference model. A parameterized formula for the bed load sediment transport and a sediment conservation equation were applied to investigate the morphodynamics of the sea bottom of the lagoon. The predicted currents pattern allowed identifying a zone where tidal waves, entering into the lagoon throughout the northern and southern openings, meet. This process had consequences on the bed load transport of sediment. The results revealed areas where the currents induce noticeable erosion and accretion processes. The complex geometry of the lagoon seems to determine the accretion and erosion areas. Important changes of the order of 0.04 m per year were predicted nearby the Northern inlet and around the Talchichitle Island. The lagoon system exports sediment through the two inlets. This research work contributes to the understanding of the sediment dynamics in an extensive region with a series of coastal lagoons located on the eastern side of the Gulf of California.

Coastal Depositional Responses to Relative Sea-Level Rise: Insights from a Superimposed Sandstone–Shale–Coal Reservoir in the Linxing Gas Field, China

“…Coastal sediment dynamics are well explored in a modern horizontal 2-D context in both estuaries [13,14,[17][18][19][20] and back-barrier lagoons [21][22][23][24][25][26]. For example, Franz, Pinto, Ascione, Mateus, Fernandes, Leitão, and Neves [20] investigated the influence of the hydrodynamics (tidal currents and wind waves) on the cohesive sediment dynamics in the Tagus estuary, Portugal using the MOHID water modeling system [27].…”