Carbonate sediments shoal-water

It is convenient to divide the deposition of carbonates in marine sediments into those being deposited in shallow (shoal) water (water depths of a few hundred meters or less) and those being deposited in deep sea sediments, where the water depth is on the order of kilometers. The primary reasons for this division are the differing sources, dominant mineralogies, and accumulation processes operative in these environments. Shoal water carbonates are the topic of Chapter 5. Naturally, there are "grey" areas of intermediate characteristics between these two extremes, such as continental slopes and the flanks of carbonate banks and atolls. 

In the present ocean calcium carbonate formation is dominated by pelagic plants (coccolithophores) and animals (foraminifera, pteropods, and heteropods). Examples are presented in Figure 4.13. Although benthic organisms are important in shoal water sediments, and for dating and geochemical studies in the deep sea sediments, they constitute only a minor portion of the calcium carbonate removed from deep seawater. Shoal water carbonates are discussed in detail in Chapter 5. 

Composition and Source of Shoal-Water Carbonate Sediments... 

In this chapter and the following, shoal-water ("shallow-water") carbonate sediments, and the seawaters they form from, are examined. Emphasis is on the biogeochemical processes affecting carbonate materials in this global marine environment, not on the general sedimentology of shoal-water carbonate deposits. The latter subject is discussed in innumerable publications such as "Carbonate Depositional Environments" (Scholle et al., 1983), to which the reader is referred. 

I g o COMPOSITION AND SOURCE OF SHOAL-WATER CARBONATE SEDIMENTS... 

The melange of carbonate particle compositions found in modem shoal-water carbonate sediments is to a significant extent the starting materials for... 

---