Sediment global distribution

The global distribution patterns of kaolinite, chlorite, montmorillonite, and illite in pelagic sediments are listed in Table 14.3 and illustrated in Figures 14.8 through 14.11. 

A global map of quartz abundance is given in Figure 14.12. In this case, the contribution of quartz is presented as the contribution to the bulk sediment from which biogenic carbonate and silica have been removed. This map is very similar to the global distribution of dust presented in Figure 11.4, reflecting the importance of aeolian transport for this detrital silicate. 

In the preceding sections, we have discussed the marine processes that control calcium carbonate s formation, dissolution, and delivery to the seafloor. Their combined effects determine the geographic distribution of calcium carbonate in marine sediments seen in Figure 15.5. As noted earlier, the global distribution of calcareous sediments does not seem to follow that of plankton production. This points to the overriding importance of the processes that control the dissolution and sedimentation of calcium carbonate. 

Global distribution pattern of the TOC content In surface sediments (<5cm depth). Source Redrawn from Seller, K., et al. (2004). Deep-Sea Research I 51, 2001-2026. 

Figure 7.2. Structural model suggested for soot according to Sergides (1987) (redrawn from Schmidt, M. W. I., and Noack, A. G. (2000). Black carbon in soils and sediments Analysis, distribution, implications, and current challenges. Global Biogeochem. Cycl. 14,777-793, with permission from the American Geophysical Union.).

Klauda, ).B. and Sandler, S.I. (2005) Global distribution of methane hydrate in ocean sediments. Energ. Fuel, 19, 459. 

Figure 10 Global distribution of the wt.% CaCOs in surface sediments of the deep ocean (>1,000 m) (source...

Figure 15 The global distribution of Si02 in marine sediments in weight percent (after Broecker and Peng, 1982).

Laflamme R. E. and Hites R. A. (1978) The global distribution of polycyclic aromatic hydrocarbons in recent sediments. Geochim. Cosmochim. Acta 42, 289-303. 

Agudo, E. G. (1998). Global distribution of ( s inputs for soil erosion and sedimentation studies. In Use of C.s in the Study of Soil Erosion and Sedimentation, LAEA-TEC DOC-1028, International Atomic Energy Agency, Vienna, Austria, 117-121. 

As for other constituents of the atmosphere, it is possible to set up a mass budget of the aerosol and to calculate its residence time. The main problem is to characterize the global distribution of particulate matter in order to determine its total mass in the troposphere. One may then apply the emission estimates of Table 7-11 to calculate the tropospheric residence time ta with the help of Eq. (4-11). This approach will be discussed in the first part of this section. Subsequently, we consider an independent method for estimating the residence time, which results from the use of radioactive tracers. Finally, the removal of aerosol particles by sedimentation and impactation at the Earth surface will be discussed. 

Additional support for the airborne transport of PAH is suggested by the results on the global distribution of PAH reported here. Thus, airborne transport of combustion-generated PAH from the New York City area to the sediments along the transect studied (Figure 5) is quite likely, especially since aeolian transport of land-derived material in this region has been documented (30). 

Fig. 12.8 Global distribution pattern of the organic carbon content (TOC) in surface sediments (<5 cm sediment depth) (with permission from Elsevier reprinted from Seiter et al. 2004).

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