| Summary: | This study provides a Holocene relative sea-level reconstruction of the White Sea, Russia. Accurate relative sea-level reconstructions calibrate Earth-ice models that are used in analyzing global satellite data such as data from the Gravity Recovery and Climate Experiment (GRACE) and provide context for modern sea-level change. Foraminifera from a core of salt-marsh peat taken above the current high tide line were used as sea-level indicators to reconstruct relative sea level along the southern coast of the White Sea in northwestern Russia. Analysis of modern salt-marsh foraminifera show a marsh dominated by two species: Balticammina pseudomacrescens in the high marsh and Miliammina spp. in the lower marsh. Partitioning around medoids statistical analysis shows four primary groups of foraminifera and their relationship to mean tide level, representing high marsh, low marsh, sub-tidal, and freshwater upland ecological zones. Analysis of foraminifera in the core show an abundance of B. pseudomacrescens, placing core samples into the high marsh zone. Relative sea level was calculated to be 2.33 ± 0.59 m higher than it is today, indicating relative sea level fall. Radiocarbon dates from plant samples above and below the analyzed marsh samples in the core constrained the sea level change to 2804 ± 52 years before present (BP; 1950AD). Comparing these data to a predicted sea level curve shows a lower than expected relative sea level. This may be due to local effects such as tectonics or subsidence, or to an inconsistency with the assumed mantle characteristics indicating that a reevaluation of mantle properties may be necessary.
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