et al., 1982; Wahsner et al., 1999; Stein, 2008 among
others) as well as the world ocean (Griffin et al., 1968;
Rateev et al., 1969; Windom, 1976; Rateev et al., 2008)
has been studied thoroughly over the past decades. The
distribution patterns of the four main clay minerals have
been related to latitudinal climate regimes, weathering
conditions, wind regimes, river discharge, and ocean currents. Kaolinite concentrations display prominent maxima
in low latitudes characterized by maximum chemical
weathering (Figure 2a). Illite reaches maximum values in
the mid to higher latitudes, especially in the northern
oceans (Figure 2b) surrounded by large land masses, and
is indicative of terrigenous origin and fluvial and eolian
supply. Maximum concentrations of chlorite are observed
in the high northern and southern latitudes (Figure 2c),
i.e., the subpolar regions characterized by predominantly
physical weathering processes. Smectite indicative for a
volcanic origin displays maximum abundance in the
South Pacific (Figure 2d), i.e., a region of intense volcanic
activity and low sedimentation rates due to the large distance to the continents and, thus, limited dilution by detrital clay minerals.
Based on the relationship between clay mineral distribution pattern in surface sediments and modern climatic
Clay Minerals, Figure 1 Diagrammatic sketch of kaolinite, montmorillonite, chlorite, and illite/mica (from Poppe et al., 2010: (http://
pubs.usgs.gov/of/2001/of01-041/htmldocs/clays/kaogr.htm; Webpage 2010; supplemented)).
CLAY MINERALS
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