GSA 2020 Connects Online

Paper No. 58-6
Presentation Time: 11:10 AM

A REVIEW OF LAST INTERGLACIAL SEA-LEVEL INDICATORS IN THE SOUTHERN WESTERN ATLANTIC: STATE-OF-THE-ART AND FUTURE PERSPECTIVES


RUBIO-SANDOVAL, Karla1, RYAN, Deirdre D.1, VACCHI, Matteo2, RICHIANO, Sebastian3 and ROVERE, Alessio1, (1)MARUM, University of Bremen, Bremen, 28359, Germany, (2)Dipartimento di Scienze della Terra, Università di Pisa, Pisa, Italy, (3)Patagonian Institute of Geology and Paleontology, Puerto Madryn, Chubut, Argentina

Interglacials are generally characterized by warmer temperatures and smaller-than-present ice sheets. In particular, the Last Interglacial (LIG, ~128-116 ka) is often regarded as a process-analog for a future climate. During this period, global average temperatures were 2°C higher than pre-industrial time, and the global mean sea level was higher. Estimates of LIG sea-levels in the Southern Western Atlantic coasts (from Brazil northwards to Colombia) range approximately from 2 to 12 m above the present level; however, there are large uncertainties associated with these values. We use the World Atlas of Last Interglacial Shorelines (WALIS) database to standardize and evaluate the quality of the sea-level record and its uncertainties. Using WALIS, we reviewed published data for the countries of Brazil, French Guiana, Surinam, Guyana, Venezuela, Colombia, as well as the islands Bonaire, Curaçao and Aruba, documenting and standardizing both geological and chronological information. While not all the reviewed papers fulfilled the database standards (e.g. missing or unclear information), the review allowed us to estimate the current state-of-the-art. Sea-level indicators are well preserved in the Southern Western Atlantic providing an almost continuous record between the states. Despite this and the relative sea-level indicators variety, there are main gaps related to the accuracy of elevation measurements and the reliability of chronology; uncertainties that hinder our ability to precisely estimate effects causing departures from eustasy. Improve our knowledge of sea-level changes during the LIG is a key to assess the future of the coastlines under warmer climatic conditions.