Contemporary salt-marsh foraminifera from southern california and implications for reconstructing late holocene sea-level changes

We report on the distribution of contemporary foraminifera in salt marshes in Mission Bay and Carpinteria Slough, South-ern California. Combining these data with existing datasets from Seal Beach and Tijuana, we explore the potential for a regional training set to underpin quantitative reconstruc-tions of paleoenvironmental change from foraminifera pre-served in salt-marsh sediments. We demonstrate that species' distributions are highly dependent on elevation, suggesting fossil foraminiferal assemblages here, as in many other re-gions, are useful depositional elevation indicators. Transfer functions provide predictions from Mission Bay cores with decimeter-scale uncertainties. Nevertheless, interpretation of marsh-surface elevation change is complicated by a complex geomorphic setting and anthropogenic impacts. An abrupt change in elevation in the mid-1700s may be related to lat-eral spreading of water-saturated sediments during an earth-quake on the Rose Canyon fault, suggesting the potential for foraminifera to support new palaeoseismic and sea-level records for the region.