Morphodynamics of Godavari Tidal Inlets

Abstract

Evolution of new features or elope of existing features on the coast may affect the entire coastal system. The morphodynamics of coastal systems implies the nature and time-varying behaviour of coastal landforms and the mechanisms that control this behaviour within specific temporal and spatial scales. Morphodynamic analysis of shoreline helps in understanding the evolution of new feature in response to seasonal and episodic events causing changes in wave direction, alongshore sediment transport, bathymetry and shoreline orientation etc. Changes in inlet morphology depict the mechanism of interaction between inlet currents and long shore sediment transport. Spit is a landform that develops where a re-entrant occurs in bay or river mouth. Geologists consider the development of barrier spit and formation of lagoon environment as a progradation process (Ramakumar, 2000). The movement of sediment along a shore forms spits by long shore drift. Where the direction of the shore turns inland (reenters), the longshore current spreads out or dissipates. No longer are currents able to carry the full load, much of the sediment are dropped. This causes a bar to build out from the shore, eventually becoming a spit. Understanding of spit geometry evolution through analytical models provide several controlling parameters (Nicolas, 1999), which makes the study complicated. This study becomes possible and easy, if temporal remotely sensed data is used. Temporal remote sensing data provides a clear picture of the significant and interesting long term and short tem changes in the spit geometry and evolution.