The relative utility of foraminifera and diatoms for reconstructing late Holocene sea-level change in North Carolina, USA

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• 作者：Andrew C. Kemp ; Benjamin P. Horton ; D. Reide Corbett ; Stephen J. Culver ; Robin J. Edwards ; Orson van de Plassche
• 关键词：Foraminifera ; Diatoms ; Transfer function ; Sea level ; North Carolina
• 刊名：Quaternary Research
• 出版年：2009
• 出版时间：January 2009
• 年：2009
• 卷：71
• 期：1
• 页码：9-21
• 全文大小：1095 K

文摘

Foraminifera and diatoms preserved in salt-marsh sediments have been used to produce high-resolution records of Holocene relative sea-level (RSL) change. To determine which of these microfossil groups is most appropriate for this purpose we investigated their relative utility from salt marshes in North Carolina, USA. Regional-scale transfer functions were developed using foraminifera, diatoms and a combination of both (multi-proxy) from three salt marshes (Oregon Inlet, Currituck Barrier Island and Pea Island). We evaluated each approach on the basis of transfer-function performance. Foraminifera, diatoms and multi-proxy-based transfer functions all demonstrated a strong relationship between observed and predicted elevations (r²_jack > 0.74 and RMSEP < 0.05 m), suggesting that they have equal utility. Application of the transfer functions to a fossil core from Salvo to reconstruct former sea levels enabled us to consider relative utility in light of ‘paleo-performance’. Fossil foraminifera had strong modern analogues, whilst diatoms had poor modern analogues making them unreliable. This result reflects the high diversity and site-specific distribution of modern diatoms. Consequently, we used foraminifera to reconstruct RSL change for the period since  AD 1800 using a ²¹⁰Pb- and ¹⁴C-based chronology, and we were able to reconcile this with tide-gauge records.