Effect of tide range on equilibrium of section-area of inlet of estuaries

Subject Areas : Marine Physics

A.  Karami Khaniki ¹ (Soil Conservation and Watershed Management Research Institute (SCWMRI))
F.  Bakhshandeh ² (Islamic Azad University, Science and Research Branch)
K.  Lari ³ (Faculty of Marine Science & Technology, Islamic Azad University, North Tehran Branch)

Received: 2011-10-19 Accepted : 2012-02-26 Published : 2012-06-20

Keywords: tidal current, area cross-section, tidal prism,

Abstract :

Estuary inlets are important elements influencing control of sediment movement and its distribution on the coast. Wave, current and sediment interaction can have a significant impact on inlets’ profile. At the bottleneck, the point where the minimum entry level is created, dominant force for transport of sediment is tidal fluctuations. Known empirical relationship between cross-sectional area at the inlet (A) and tidal prism (P) has been studied by various workers. Researchers have carried out extensive studies on A and Prelation in which A is the minimum cross-section area (in comparison with average sea level) and P is tidal prism. Their input on 28 estuaries of the United States showed high-coefficient values in a table in which C= 4.6 × 10 -4 and n= 0.85 also C= 6.5 × 10 -5 and n= 1 are the best values (high regression coefficient) for these coefficients. Various researchers continued these studies and could provide a relation that is far right applicable to other coastal areas with different tidal patterns. Results of studying n and c coefficients by Marcel was expressed that for various estuaries and tidal ranges of microtidal to mesotidal, one is the best power for n. In the following research using outputs of modeling the relationship between canal cross-section area with tidal prism was studied and c and n=1 coefficients were calculated, respectively, 2×10 -5 and 6×10 -6 for modeling and relationship theory (dean). Then we compared results between the theory and modeling. We also observed a direct relationship between the two parameters of channel cross-sectional area and tidal prism. Relationships were presented for inlets’ section width and tidal prism.