Carbonate platforms

Platform carbonates Massive concretions of calcium carbonate in neritic sediments deposited by corals, corraUne algae and other organisms that deposit calcareous hard parts. 

Foley, N. K. 2002. Chapter E, Environmental geochemistry of platform carbonate hosted sulfide deposits. In Seal II, R. R. Foley, N. K. (eds) Progress on Geoenvironmental Models for... 

Walter L. M. and Burton E. A. (1990) Dissolution of recent platform carbonate sediments in marine pore fluids. Am. J. Sci. 290, 601-643. 

Havorka, S. D., Dutton, A. R., Ruppel, S. C., and Yeh, J. S., 1996, Edwards aquifer ground-water resources geologic controls on porosity de elopment in platform carbonates, South Texas, The University of Texas, Bureau of Economic Geology, Report of Investigations, 238, Austin, 75 p. 

A series of additional alterations of the graphite tube atomizer intended to improve performance (e.g. the cup and cup cuvette atomizer, boat and microboat platforms, carbon rods, graphite probes, ring chambers and surface atomizers) have also been reported [23]. Interested readers are referred to specific sources [2-7] for more details. 

The sedimentary section of the U.S. southern midcontinent consists in large part of Paleozoic platform carbonate rocks interbedded with shale and subordinate sandstone. As documented below, a large volume of the Paleozoic carbonate rocks in this region is enriched in arsenic, as well as lead, zinc, copper, cobalt, molybdenum, and nickel compared to surrounding carbonate strata (Erickson et al., 1981 Lee and Goldhaber, 2001). In plan view this trace-mineralized area extends over thousands of square kilometers. The widespread metal enrichment process was related to the formation of much more spatially localized ore districts. These districts consist of economic concentrations of the ore elements zinc and lead, and to a lesser extent copper, cobalt, and barium that occur in the platform... 

Amthor, J.E. Friedman, G.E. (1992) Early- to late-diagenetic dolomitization of platform carbonates lower Ordovician Ellenburger Group, Permian Basin, West Texas. 7. sediment. Petrol., 62, 131-144. 

Moss, S. Tucker, M.E. (1995) Diagenesis of Barremian-Aptian platform carbonates (the Urgonian Limestone Formation of SE France) near-surface and shallow-burial diagenesis. Sedimentology, 42, 853-874. 

These platforms are the second important tropical to subtropical environment where high amounts of carbonate are produced and accumulated at water depths shallower than 50 m. The areal extension is about 0.8-10 km In contrast to reefs, on carbonate platforms production is mainly carried out by benthic red/green algae, mollusks and benthic foraminifera. Estimates of biotic and, to a much lesser extent, abiotic carbonate production on platforms range between 300-500 g CaCO m yr , which amounts to 4-10 mol yr on a global scale. Accumulation of platform carbonate is difficult to assess because a lot of it is dissolved or can be found as exported material in several 10 to 100 m... 

Carbonate reef Platform carbonates Basinal elastics... 

Montanez 1. P., Banner J. C., Osleger D. A., Borg L. E. and Bosserman P. J. (1996) Integrated Sr isotope variations and sea-level history of Middle to Upper Cambrian platform carbonates implications for the evolution of Cambrian sea water Sr/ Sr. Geology 24, 917-920. 

Goldhammer, R.K., Dunn, P.A., and Hardie, L.A. 1990. Depositional cycles, composite sea-level changes, cycle stacking patterns, and the heirarchy of stratigraphic forcing Examples from Alpine Triassic platform carbonates. Geological Society of America Bulletin, 102 535-562. 

Jones, B., and Desrochers, A. 1992. Shallow platform carbonates. In Facies Models Response to Sea-Level Changes, Walker, R.G., and James, N.P, eds.. Geological Association of Canada, St. John s, Canada, pp. 177-301. 

Bonanni et al. report the impedimetric detection of transgenic insect-resistant Bt maize DNA, using carbon nanotubes as sensing platform. Carbon nanotubes were modified with carboxylic groups which allowed the covalent immobilization of the oligonucleotide sequence under study (Figure 14.19). The impedimetric technique allowed either the detection of complementary DNA sequences or their quantification. 

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