Influence of Submarine Canyons on Intrusion of Ocean Water into Fresh-Water Aquifer: ABSTRACT

Abstract

Detailed hydrologic studies along the California, coast reveal that important fresh-water aquifers are exposed in submarine canyons or, if not exposed, are in hydraulic continuity with the ocean in the canyons. In the typical aquifer, which has a low-angle seaward dip, the effect of submarine canyons is to produce submarine outcrops abnormally close to shore. Under natural conditions, especially during wet cycles, the piezometric surface had a strong seaward slope and fresh water escaped at the submarine outcrops, especially those in the submarine canyons. The volume of stored fresh water in the submarine extensions of the aquifer is reduced by an amount proportional to the volume of the End_Page 187------------------------------ aquifer removed during the formation of the canyon. Accompanying excessive pumping of the aquifer will be the development of a landward slope of the piezometric surface and the intrusion of ocean water into the submarine area of the aquifer. The first water wells abandoned because of ocean water will most likely be in the vicinity of the submarine canyons. End_of_Article - Last_Page 188------------