Geology Reference
In-Depth Information
Main features
Examples with important references
Great Bahama Bank
Anselmetti et al. 2000; Ball 1967; Curran and White 1995; Eberli and Ginsburg
1989; Ginsburg et al. 1991; Hardie 1977; Harris 1979; Hine 1977; Milliman et al.
1993; Newell et al. 1959; Neumann and Land 1975; Purdy 1963a; 1963b; Schlager
and Ginsburg 1981; Shinn et al. 1969; Wanless and Dravis 1989; Ginsburg 2001
Shallow sea floor (~100 m
average depth); topograph-
ical fringing barriers (reefs,
shoals, islands) at the sea-
ward margin; low-energy
environments and mud
deposition within the shelf
lagoon, high-energy environ-
ments predominantly at the
outer margins
South Florida Shelf
Bosence 1989; Enos and Perkins 1977; Ginsburg 1956; Halley et al. 1983; Mess-
ing et al. 1990; Multer 1969; Shinn 1963; Shinn 1983; Shinn et al. 1989; Stock-
man et al. 1967; Turmel and Swanson 1976
Cuba
Bandy 1964; Daetwyler and Kidwell 1959; Bathurst 1975
Belize
Gischler and Lomando 1999; Gischler et al. 2000; James and Ginsburg 1979;
Purdy 1974; Purdy et al. 1975; Scholle and Kling 1972
Great Barrier Reef
Drew 1983; Gagan et al. 1990; Larcombe and Woolfe 1999; Maiklem 1968; Max-
well 1968; Maxwell and Swinchatt 1970; Scoffin and Tudhope 1985; Tudhope
1989
Sea floor gently inclined
towards the shelf break;
sedimentation controlled by
wave action, and tidal and
oceanic currents; calcareous
sands in shallow settings;
mud in deeper settings; wide
irregular facies belts; lack of
resedimentation by mass
flow mechanism
Northwestern Yucatan
Folk 1967; Folk and Robles 1964; Gischler and Lomando 1999; Hoskin 1963;
Logan et al. 1969; Viniegra-Osario 1981; Wilson 1970; Ward and Brady 1973
Eastern Gulf of Mexico
Folk et al. 1962; Gardulski et al. 1986; Rezak et al. 1985; Siringan and Anderson
1994
Persian Gulf
Houbolt 1957; Patterson and Kinsman 1981; Purser 1973; Scholle and Kinsman
1974
Fig. 2.10.
Major settings of modern subtropical shelf carbonates (based on Sellwood 1986).
glacial stage. Facies distribution and setting of modern
reefs and shoals, therefore, are strongly controlled by
the Pleistocene topography (Purdy 1974).
Excellent reviews and detailed descriptions of mod-
ern tropical and subtropical shelf carbonates from dif-
ferent settings can be found in Sellwood (1986), Tucker
and Wright (1990), Jones and Desrochers (1992), and
Wright and Burchette (1996). In the context of inter-
preting of microfacies data, these references must be
thoroughly consulted.
definitions and significance of these constituents are
discussed in Sect. 4.2. Plate 3 offers a first look at the
diversity of the grain types.
Reefs
Modern tropical and subtropical reefs are situated
at shelf and platform margins, and on shelves, platforms
and ramps. The distributional pattern of recent coral
reefs suggests that reefs are arranged nearly symmetri-
cally in both hemispheres, do not occur at latitudes
greater than 34°, are concentrated at the western mar-
gins of the oceans, are absent in the vicinity of large
river mouths, and exhibit two reef realms (Caribbean
and Indo-Pacific realm).
Furthergoing explanation of the distributional pat-
tern suggests that reefs prefer shallow waters and tropi-
cal to subtropical climates, and can grow in land-locked
settings and in open oceanic settings, and that reefs
avoid settings with high clastic input and areas affected
by cool eastern boundary currents and coastal up-
welling. In summary, sea-water temperature, sunlight
Composition of tropical and subtropical shallow-ma-
rine carbonates:
Similar to ancient limestones, mod-
ern warm-water shelf carbonates consist of polygen-
etic carbonate mud and different categories of grains.
Grains include biogenic material (detrital bioclasts or
in situ calcareous organisms), sand-sized grains of mud-
grade carbonate (peloids), various coated grains (oo-
ids, oncoids, rhodoids), sand-sized aggregates of ag-
glutinated particles (grapestones), and lithified and re-
worked sediment clasts (lithoclasts, intraclasts). The
