Last interglacial sea level along the Patagonian coast
As part of the World Atlas of Last Interglacial Shorelines (WALIS), we critically review existing chronologically constrained last interglacial sea level indicators along the coast of Patagonia in Argentina, South America. Since Charles Darwin's voyages on the Beagle in the 1830s, the staircase-like shoreline platforms along the Patagonian coast have been used as evidence that it has been subject to uplift. Paleo-sea level indicators, ranging between about 7 and 24 m have been attributed to the Last Interglacial on the basis of electron spin resonance and U/Th dating on mollusc shells, and shows remarkable continuity along the entire coast. If the age of these indicators are accurate, then it would indicate that there is a significant uplift rate during the past 120,000 years, since these values exceed the generally accepted peak globally averaged sea level for the last interglacial. However, the Patagonian coast is close enough to the Antarctic and Patagonian ice sheets that there could be a signal from glacial-isostatic adjustment (GIA). This might be an alternative explanation for these higher than average paleo-sea level values. We test the magnitude of the effect of GIA on the coast of Patagonia using a simple ice reconstruction spanning the past two glacial cycles, using a variety of Earth models.
Helmholtz Research Programs > PACES II (2014-2020) > TOPIC 3: The earth system from a polar perspective > WP 3.2: Earth system on tectonic time scales: From greenhouse to icehouse world