Stratigraphic, sedimentologic (including CT 3D X-ray tomography scans), foraminiferal, and radiocarbon analyses show that at least six of seven abrupt peat-to-mud contacts in cores from a tidal marsh at Talbot Creek (South Slough, Coos Bay), record sudden subsidence (relative sea-level rise) during great megathrust earthquakes at the Cascadia subduction zone. Data for one contact are insufficient to infer whether or not it records a great earthquake-it may also have formed through local, non-seismic, hydrographic processes. To estimate the amount of subsidence marked by each contact, we expanded a previous regional modern foraminiferal dataset to 174 samples from six Oregon estuaries. Using a transfer function derived from the new dataset, estimates of coseismic subsidence across the six earthquake contacts vary from 0.31 m to 0.75 m. Comparison of subsidence estimates for three contacts in adjacent cores shows within-site differences of ≤0.10 m, about half the ± 0.22 m error, although some estimates may be minimums due to uncertain ecological preferences for Balticammina pseudomacrescens in brackish environments and almost monospecific assemblages of Miliammina fusca on tidal flats. We also account for the influence of taphonomic processes, such as infiltration of mud with mixed foraminiferal assemblages into peat, on subsidence estimates. Comparisons of our subsidence estimates with values for correlative contacts at other Oregon sites suggest that some of our estimates are minimums and that Cascadia's megathrust earthquake ruptures have been heterogeneous over the past 3500 years. 2 Setting We studied the stratigraphy beneath a small tidal marsh near the head of a 100-m-wide, steepsided valley drained by Talbot Creek in a heavily forested part of the South Slough National Estuarine Research Reserve (NERR), a federally protected part of the Coos Bay estuary in southern Oregon (Figs. 1B-D; Rumrill, 2006). Grazing with modest drainage and compaction (Caldera, 1995; Cornu and Sadro, 2002) of the upper few tens of centimeters of sediment has not disturbed the stratigraphy beneath formerly diked marshes in South Slough (Nelson et al., 1996b; 1998). At the Charleston NOAA tide gauge station, at the mouth of South Slough, the observed great diurnal range (Mean Highest High Water, MHHW-Mean Lowest Low Water, MLLW) is 2.32 m (ID 9432780; http://tidesandcurrents.noaa.gov/index.shtml). Vascular plant communities near our core site in the Talbot Creek marsh are dominated by typical middle-tohigh marsh flora including Distichlis spicata, Carex lyngbeyi, and Deschampsia cespitosa, with common Triglochin maritima, Argentina egedii, and Agrostis alba. We selected the Talbot Creek site near the southern end of South Slough (Fig. 1C and D) because the existing tidal-marsh stratigraphic framework (Nelson, 1992; Ota et al., 1995; Nelson et al., 1996b; 1998; Figs. A1 and A2) shows that this estuary has an unusually long and distinct record of earthquake subsidence, and so is a key paleoseismic site along the Cascadia subduction zon...

A total of 288 modern benthic carbonate shelf foraminifera in three areas of the Western Mediterranean Sea (Alboran Platform, Oran Bight and the southwest shelf of Mallorca) have been studied and are systematically listed. This systematic description provides a list of synonyms, short remarks about morphological features of the taxa and some annotations about taxa with problematic generic status. Most of the taxa are illustrated by SEM photographs.

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The pore-densities (PD) in the tests of 232 specimens of the shallow infaunal foraminiferal species Bolivina spissa from eight locations off the Peruvian continental margin were investigated and compared to different environmental factors as water-depth, temperature, bottom-water oxygen ([O 2 ] BW ) and nitrate concentrations ([NO 3 2 ] BW ). There is a negative exponential PD-[O 2 ] BW correlation, but at oxygen-concentrations >10 mmol/l PD approaches a constant value without any further correlation to [O 2 ] BW . The PD-[NO 3 2 ] BW relationship is better constrained than that for PD-[O 2 ] BW .We hypothesize that the pores in the tests of B. spissa largely reflect the intracellular nitrate, and to a smaller extent the oxygen respiration. We also compared PD and porosity (P) of two single B.spissa and B.seminuda specimens from the same habitat. The comparison showed that P is significantly higher in B.seminuda than in B. spissa indicating that B.seminuda is much better adapted to strong oxygen-depleted habitats than B.spissa.