Sediment echosounder records (18 KHz) of 14 profiles were made in the
fjord-like embayment of Golfo Dulce, Pacific of Costa Rica, to investi
gate morphology and sediment structure. The NW-SW section includes an
oriental fault that is the main internal tectonic characteristic of th
e Gulf; that has a very steep slope and reaches 170 m in height. Two p
arallel, but less prominent tectonic faults are also evident on the ec
hographs. The sediments in the flat inner basin consist mainly of turb
idites, which reach the deepest part of Golfo Dulce by channels, leavi
ng most of the slope sediments unaffected.