Sedimentary systems of coastal-plain estuaries

This chapter discusses the expression of fundamental, estuarine characteristics in a particular geologic setting—the coastal plain. An estuary is a semi-enclosed coastal body of water that extends to the effective limit of tidal influence within which sea water entering from one or more free connections with the open ocean, or any other saline coastal body of water, is significantly diluted with fresh water derived from land drainage and can sustain euryhaline biological species for either part or the whole of their life cycle. An understanding of coastal-plain estuaries may be biased by estuaries along the east coast of the U.S. and in the Netherlands. The information base needs to be further expanded to a widened range of climates, hydrologic, and geomorphic settings. This process can be expedited by continued development of a classification scheme for the sedimentary system of coastal-plain estuaries. To bridge the gap between the oceanographic characterization of estuaries and facies models, the state of the estuarine sediment transport system must be defined, including (1) the stability of sand deposits at the estuary mouth, (2) the fluxes of fine-grained sediment at the estuary floor, and (3) the trapping efficiency of the estuary.