Karst processes and estuarine coastlines

Abstract

Estuaries with part, or all, of their perimeter contained by soluble rocks will display differences from those estuaries developed in non-carbonate rock or sediments. Flank margin caves are the most notable difference and can create coastline irregularities and specialty habitats. These caves can also provide evidence of paleo-estuary conditions when other evidence has been removed by erosion. Freshwater input to the estuary may approach conditions similar to typical diffuse groundwater flow if the soluble rocks are eogenetic. If the soluble rocks are telogenetic, then conduit-flow additions to the estuary can occur at multiple discrete points along the estuary perimeter that may not be obvious to casual observation. Accurate assessment of an estuary developed in carbonate rocks cannot be done without an awareness of how karst processes are participating in coastline development, habitat placement, and freshwater flow.