Chapter 3: Geological changes in coastal areas of Patagonia, Argentina and Chile

ISLA FEDERICO IGNACIO; ISLA, MANUEL F.

Global change in Atlantic coastal Patagonian ecosystems: A journey through time

Springer-Nature

Año: 2021; p. 73 - 90

The Patagonian coast evolved in relation to different issues. An arid climate dominates to thenorth while very humid conditions prevail to the south of the Pacific coast and at the FueguianArchipielago. Tidal effects increase from north to south at the Atlantic coast, while the Pacificcoast is dominantly microtidal. Patagonia has been uplifting in relation to the Andes Mountains;at the Atlantic coast the uplift increases towards the south. Marine terraces originated by theQuaternary sea-level fluctuations that developed in response to the sediment availability. Thecliffy Atlantic coast is receding at a rate between 0.3 and 1.4 m/yr. Reversals in the direction ofriver discharges changed the supply of sediment to the coast; dams constructed at the piedmontsalso caused these sediment shortages. Gravel availability contributed to the armouring ofbeaches and the longshore growing of spits. In many places these barriers are protectingmarshes and tidal flats against the sea level rise.