Reefs carbonate

Shallow water carbonate (reefs carbonate muds) Reservoir quality governed by diagenetic processes and structural history (fracturing). Prolific production from karstified carbonates. High and early water production possible. Dual porosity systems in fractured carbonates. Dolomites may produce H S. 

Friedman, G.M., 1968. Geology and geochemistry of reefs, carbonate sediments, and waters. Gulf of Aqaba (Elat), Red Sea. J. Sediment. Petrol., 38 895—919. 

Aragonite. Calcium carbonate is a common deposit in shallow tropical waters as a constituent of muds, or in the upper part of coral reefs where it precipitates from carbon dioxide-rich waters supersaturated with carbonate from intense biological photosynthesis and solar heating. Deposits of ooHtic aragonite, CaCO, extending over 250,000 km in water less than 5 m deep ate mined for industrial purposes in the Bahamas for export to the United States (19). 

Keegan, W.F. and DeNiro, M.J. 1988 Stable carbon- and nitrogen- isotope ratios of bone collagen used to study coral-reef and terrestrial components of prehistoric Bahamian diet. American Antiquity 53 320-336. 

Magnesium Carbonate MgCOj Magnesite Reef corals Skeletal... 

In addition to climate change, the increased atmospheric concentration of C02 is likely to have wide-spread ecological effects in various environments, since C02 is a physiologically active gas, in plants as well as animals. The acidic nature of C02 will also lead to changes in the chemistry of the ocean s surface, which is in equilibrium with the atmosphere. Once the shift in the oceanic chemical balance becomes significant, it will affect ecosystems. It has been shown, for example, that doubling C02 concentration in the atmosphere will reduce the rate of calcium carbonate deposition in coral reefs by 30-40% (Langdon et al., 2000). 

Langdon, C., Takahashi, T., Sweeney, C., Chipman, D., Goddard, J., Marubini, F., Aceves, H., Barnett, H., and Atkinson, M.J., Effect of calcium carbonate saturation state on the calcification rate of an experimental coral reef, Global Biogeochem. Cy., 14, 639-654,2000. 

One of the major problems associated with beneficiation of PGM from sulphide-dominated deposits is the presence of hydrophobic gangues, such as talc, chlorites, carbonates and aluminosilicates. The concentrates produced in most of the Morensky Reef operations (South Africa) varies from 80 to 150 g/t of combined PGM, where most of the contaminants are silicates, aluminosilicates and talc (i.e. up to 60%). The major hydrophobic gangue depressants used are carboxymethyl cellulose (CMC) and different modifications of guar gums. 

Mangrove Forest ecosystems occur on the surface of compact cavernous reef limestone or on carbonate sands, aleuritic and clayey silts in lagoons and shallow... 

Thus, with a variable degree of empiricity, mass transfer coefficients for a number of biologically relevant cases have been described phytoplankton uptake [60], periphyton uptake [61], coral-reef supply of nutrients [62-64], fixation of carbon at leaf surfaces [65], etc. 

Stanley SM, Hardie LA (1998) Secular oscillations in the carbonate mineralogy of reef-building and sediment-producing organisms driven by tectonically forced shifts in seawater chemistry. Palaeogeography Palaeoclimatology Palaeoecology 144 3-19... 

Eggshells are mostly calcium carbonate. Seashells, pearls, limestone, and chalk are also made of calcium carbonate. So are some of the most beautiful and complex places on earth—coral reefs. 

Animals called corals build coral reefs. Corals take calcium and carbonate ions in seawater and make calcium carbonate skeletons.The ocean is naturally basic, with a pH a little above eight. When the pH is lowered, even if it s still somewhat basic, there aren t as many carbonate ions floating around and it s harder for corals to make their skeletons. When there aren t enough raw materials, the corals can t work efficiently. 

Goreau, T. F. Calcium carbonate deposition by coralline algae and corals in relation to their roles as reef-builders. Ann. N. Y. Acad. Sci. 109, 127—167 (1963). 

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