Abstract

Southwest England is an area of particular interest to sea-level studies as it has been argued to have the fastest subsiding coastline in the United Kingdom. However, this suggestion is based on very limited data and there is a need for quantitative sea-level estimates to establish an accurate regional Holocene sea-level history. Intertidal foraminifera are well suited as sea-level indicators due to their quantifiable relationships with tidal heights. In this study we analyze surface sediments from mudflats and salt marshes in the Erme and Salcombe-Kingsbridge estuaries, south Devon, to provide an intertidal foraminifera-based transfer function for reconstructing Holocene sea-level change in southwest England, UK. Foraminifera were identified from 113 contemporary salt-marsh and mudflat samples, spanning a vertical range between −2.6 m below and +2.6 m above mean tide level (MTL). Foraminiferal assemblages exhibit a distinct and comparable vertical zonation in both estuaries. Reophax spp., Eggerella scabra and Elphidium oceanensis live preferentially around MTL, and both Trochammina inflata and Haplophragmoides spp. are useful indicators of high marsh environments. Weighted averaging partial least squares regression analysis on dead assemblages, using height in relation to MTL as the dependent variable, produces a transfer function capable of predicting paleo-sea-level positions with a precision of ±0.285 m. The transfer function was applied to foraminiferal assemblages from a Holocene core and demonstrates that the modern data set can be used to quantify the height of Holocene sea-level index points from southwest England.

You do not currently have access to this article.