Sediment distribution in El Tablazo Bay, Maracaibo system, Venezuela

Abstract

The Bay of El Tablazo has an area about 640 km/sup 2/, a trapezoidal form and average dimensions of 27 km (east-west) and 24 km (north-south) and serves as communication between the Gulf of Venezuela and the Lake of Maracaibo. It is a shallow body of water with small natural channels and an artificial main navigation canal, which is constantly dredged to allow access of large boats into the Lake of Maracaibo. This present paper explains how the sediments of Bay of El Tablazo are distributed and how natural and artificial elements have had influenced their distribution. The results show that most of the sediments in the El Tablazo Bay contain less than 50% of silt and clay. Predominating in the south are the sediments that have less than 10% of silt and clay, and in the north are found to contain between 10 and 50%. Their distribution, produced by the action of different physical-chemical factors (such as the flow in and out of different density and salinity waters due to tides, the constant dredging of the canal, the artificial dikes, the winds, etc.) affect the estuary system. A comparison of these results with the ones reported in 1965, shows that sedimentation of silt and clay is increasing in the Bay of El Tablazo, perhaps indicating an accelerated advance in eutrophication processes.