Sediment record

Engstrom DR, Polhnan CD, Fitzgerald WF, Balcom PH. 2003. Evaluation of recent trends in atmospheric mercury deposition in south florida from lake-sediment records. Tallahassee (FL) Florida Department of Environmental Protection, 27 pp. 

JOHANNESSON, K.H., HAWKINS JR., D.L. Cortes, A., 2006. Do Archean chemical sediments record ancient seawater rare earth element patterns Geochimica et Cosmochmica Acta, 70, 871-890. 

Quantitative Inferences from Biotic Remains in the Sediment Record... 

Mercury Fluxes and Sediment Records. Our calculations of lakewide Hg fluxes from more than 80 dated sediment cores from seven small headwater lakes reveal a regionally consistent increase in Hg inputs from preindustrial times to the present the modern Hg flux to each of these lakes is about 3.7 times that of the early 1800s. Such increases are typical of that reported in other investigations of lake sediments from remote or rural sites in eastern North America (3, 6, 7,10, 23). Most researchers have concluded that the increase is anthropogenic and that the Hg must be transported through the atmosphere and deposited on the lake and its terrestrial catchment. 

Net sedimentation is defined as the flux of material incorporated into the permanent sediment record. 210Pb and 137Cs geochronologies indicate a mass sedimentation rate of 103 g/m2 per year for profundal sediments in Little Rock Lake. By using the mean Hg concentration (118 ng/g) in the top 1-cm slice of our bulk sediment profile, we estimated an annual net sedimentation of 12 xg of HgT/m2 per year. This net accumulation rate is similar to the calculated atmospheric input rate of about 10 xg/m2 per year (18, 19). Additionally, gross deposition rates (from sediment traps) exceeded these estimates by about a factor of 3 this rate suggests substantial internal recycling of material deposited at the sediment-water interface in this lake. 

Baumard, P., Budzinski, H., Garrigues, P., Burgeot, T., Bellocq., J., 1998. Origin and bioavailability of PAHs in the Mediterranean Sea from mussel and sediment records. Est-uar. Coast. Shelf Sci. 47, 77-90. 

Punning, M.J., T. Alliksaar, J. Terasmaa, and S. Jevrejeva. 2004. Recent patterns of sediment accumulation in a small closed eutrophic lake revealed by the sediment records. Hydrobiologia 529 71-81. 

In some deep-sea sediment columns, records of IDP fall-out can be traced back to several ten million years with the help of extraterrestrial He as a tracer. Such a remarkable example was reported by Farley (1995). Farley measured 3He/4He ratios in a pelagic sediment core drilled from the central North Pacific. The core is thought to carry a nearly complete sedimentation record to 72Ma. Figure 5.6 shows records of the He concentration and the isotopic ratio in the drilled core. 

Brassell, S.C., and Eglinton, G. (1983) The potential of organic geochemical compounds as sedimentary indicators of upwelling. In Coastal Upwelling Its Sediment Record (Suess, E., and Thiede, J., eds.), pp. 545-571, Plenum Press, New York. 

Gillan, F.T., and Johns, R.B. (1986) Chemical biomarkers for marine bacteria fatty acids and pigments. In Biological Markers in the Sediment Record (Johns, R.B., ed.), pp. 291-309, Elsevier, New York. 

Bogdal, C., Schmid, P, Kohler, M., Muller, C.E., Iozza, S., Buchell, T.D., Scheringer, M., Hungerbuhler, K., Sediment record and atmospheric deposition of brominated flame retardants and organochlorine compounds in Lake Thun, Switzerland Lessons from the past and evaluation of the present, Environmental Science and Technology, 2008, 42, 6817-6822. 

Intriguingly, despite the lack of a global LGM-Holocene change, a deglacial maximum in is observed in the majority of sediment records, followed by a... 

Unlike vanadium, REE/Fe ratios recorded in even the most recent metalliferous sediments are much higher than those in suspended hydrothermal plume particles (German et al., 1990, 1997 Sherrell et al., 1999). Further, hydrothermal sediments REE/Fe ratios increase systematically with distance away from the paleo-ridge crest (Ruhlin and Owen, 1986 Olivarez and Owen, 1989). This indicates that the REE may continue to be taken up from seawater, at and near the sediment-water interface, long after the particles settle from the plume to the seabed. Because increased uptake of dissolved REE from seawater should also be accompanied by continuing fractionation across the REE series (e.g., Rudnicki and Elderfield, 1993) reconstruction of deep-water REE patterns from preserved metalliferous sediment records remain problematic. Much more tractable, however, is the exploitation of these same sample types for isotopic reconstructions. 

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