1972; Grötsch and Flügel, 1992; Gischler, 1996). Lonsdale et al. (1972) recorded current speeds of up to
15 cm/s on the top of Horizon Guyot and observed substantial erosion due to winnowing of sediment. On the
top of guyots, flow acceleration and eddies, internal
waves, and upwelling, called Taylor columns (Boehlert
and Genin, 1987), apparently increase nutrient concentrations, enhance primary productivity, and sustain filterfeeding organisms such as soft corals, crinoids, or
sponges.
Genetic connection between atolls and guyots
In his universally known subsidence theory, Darwin
(1842) genetically connected fringing, barrier, and atoll
reefs. During the subsidence of volcanic islands, fringing
reefs develop into barrier reefs and eventually to atolls
due to vertical reef accretion. For example, the distribution
of reef types in the Society Islands (south Pacific) may be
used in support of Darwin’s theory. Away from the hot
spot toward the west, volcanic islands are progressively
older (Guillou et al., 2005) and reef types change from
Guyot, Atoll, Figure 2 (a) Seismic cross section and (b) sedimentary succession on top of Allison Guyot (modified from Winterer and
Metzler, 1984; Jenkyns and Wilson, 1999).
GUYOT, ATOLL
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