Sedimentary trace elements

Sternbeck, J., Sohlenius, G, and Hallberg, R.O. (2000) Sedimentary trace elements as proxies to depositional changes induced by a Holocene fresh-brackish water transition. Aquat. Geochem. 6, 325-345. 

Two additional lines of evidence link trends in the MTR data to coal combustion. The first is a comparison of temporal trends in IRM, Zn, and S with SO2 production in the US. This comparison is shown in Fig. 14. By far the dominant source of SO2 is fuel combustion (EPA, 2000). For the period from 1930 to about 1980, there is a close correspondence between SO2 production/combustion and reservoir geochemistry/mineralogy. In particular, SO2 production maxima during World War II (1945) and the period prior to the Clean Air Act of 1970 are mirrored by peaks in reservoir S and IRM. The correspondence between content of sedimentary trace elements and magnetite related to coal combustion with the source function for these constituents is consistent with a relation between the source and sink. 

ABSTRACT A geochemical analysis of major, trace and rare earth elements was carried out in beach sands collected from the Northeastern coast of Mexico in order to observe the spatial trends along three different beaches. Results show that major elements patterns along the beaches are controlled by heavy minerals and plutonic and sedimentary input towards the coast. In addition, trace elements tendencies indicate that the beach sands are influenced by the presence of magnetite. Finally, the differences in Eu anomalies indicate a mix of felsic to mafic and intermediate rocks and feldspar weathering. 

Trace elements and rare-earth elements (REEs) of the same calcite samples used for the stable isotope analysis have significantly lower concentration of REE as well as most trace elements relative to typical carbonatites. The total REE contents of the Ulsan carbonates range from 3 to 17 ppm, which are much lower than any igneous rocks and even lower than those of some sedimentary rocks. REE and trace-element abundances may have changed sufficiently due to alteration, thus, affecting petrogenetic... 

The factors which control the distribution of trace elements [defined arbitrarily in geochemistry as those elements present at less than 0.1 weight percent (wt %)] can be discussed under a number of headings - structural, thermodynamic, kinetic and, in the sedimentary environment, solubility and speciation. 

As shown in Table 11.3, the concentrations of trace elements in the water column is - despite anthropogenic pollution - extremely small (10 11 - 10 7 M) illustrating the remarkable efficiency of the continuous "conveyor belt" of the settling adsorbing and scavenging particles. The sedimentary record reflects the accumulation of trace elements in sediments and a profile of concentration vs sediment-depth (or age) gives a "memory record" on the loading in the past (Fig. 11.9). 

Recent work (Peter Goodfellow 2003) has documented the distribution of REE in iron formations of the BMC. Despite what is currently known of trace-element behaviour in exhalative sedimentary... 

In order to determine the source composition of sediments using trace elements, it is necessary to ascertain that the element is immobile under conditions of diagenesis and weathering (Spalletti 2008). Several ratios and plots may be used to define the source rocks. The felsic source rock compositions are found in the Co/Th vs. La/Sc diagram (Fig. 3 Table 1). Other trace element characteristics of sedimentary rocks also place some constrains on the nature of the source rock. Floyd Leveridge (1987) used a La/Sc vs. Hf plot to discriminate between different source compositions. In this plot, most data fall in the felsic source to mixed felsic/basic source field (Fig. 4 Table 1). 

Bhatia, M.R. Crook, K.A.W. 1986. Trace element characteristics of graywackes and tectonic setting discrimination of sedimentary basins. Contributions to Mineralogy and Petrology, 92, 181-193. 

Hematitic iron ores of hydrothermal-sedimentary origin and Palaeozoic in age, are those of the Lahn-Dill-type in West and Central Europe (Harder, 1964). Hydro-thermal solutions associated with submarine volcanic activities have transported Fe (as FeCl3) into a marine environment, where after hydrolysis, hematite was formed (via ferrihydrite) at the margin of the basin, whereas siderite (after reduction) was formed in its centre. These ores are - in contrast to true sedimentary ores - low in Al,Ti and trace elements, which betrays their volcanic origin. 

Veizer J. (1983) Trace elements and isotopes in sedimentary carbonates. In Carbonates Mineralogy and Chemistry, Reviews in Mineralogy, 11 (ed. R.J. Reeder), pp. 265-300. Mineral. Soc. America, Book Crafters, Incorporated, Chelsea, Ml. 

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