Geology Reference
In-Depth Information
Box 12.10.
Selected studies on ancient non-tropical carbonates.
Most studies use grain-association patterns to differen-
tiate non-tropical and tropical carbonates. Papers that can serve as a guide in comparing samples with established grain
association types are marked by an asterisk.
Tertiary:
*Bernecker and Weidlich 1990; Bernecker et
al. 1997; Betzler 1995, 1997; Betzler et al. 1993, 1995,
*1996, *1997, *2000; *Boreen and James 1992, 1995;
*Brachert et al. 1993, *2001; *Braga et al. 2001; Burgess
and Anderson 1983; Carannante et al. 1996; Clarke et al.
1996; *Cunningham and Collins 2002; *Franseen et al.
1997; *Friebe 1994; *Gammon et al. 2000; Gordon et al.
1994; *Hayton et al. 1995; *Holdgate and Gallagher 1997;
James 1991, *1997; James and Bone 1992a, 1992b, *1994,
*2000; Kamp et al. 1988; *Krautworst 1999; Lauriat-Rage
et al. 1993; *Lukasik et al. 2000; MacGregor 1983;
McGowran et al. 1997; *Mutti et al. 1999; Nebelsick *1989,
*1992, 2000; Nelson 1978, 1999; *Nelson and James 2000;
Nelson et al. *1988; Nicolaides and Wallace 1997;
*Randazzo et al. 1999; Scudeler Bacelle and Renato 1988;
Shubber et al. 1997; Simone and Carannante 1988; Spjeld-
naes and Moisette 1997; Vecsei and Sanders 1999
Cretaceous:
Carannante and Simone 1987; Carannante
et al. *1988, 1995, *1997; Gischler et al. 1994; *Simone
and Carannante 1988; *Surlyk 1997
Carboniferous and Permian:
*Beauchamp 1994;
*Beauchamp and Desrochers 1997; *Brandley and Krause
1997; Draper 1988; *Ezaki et al. 1994; Fan Yingnian 1988;
Hüneke et al. 2001; Martindale and Boreen 1997; *Rao
1981, 1988a, 1988b, *1991; Rao and Green 1982;
*Samankassou 2002, *Stemmerik 1997, 2001; Weidlich
2002
Ordovician:
*Brookfield 1988; *Dullo 1992; *Lavoie
1995; *Pope and Read 1997; Rao 1990, *1991; Rao and
Wang 1990; Grimwood et al. 1999; Webby 2002
Several points must be taken into consideration
when using grain associations as paleoclimatic prox-
ies. Cool-water associations may be controlled by fac-
tors other than just water temperature.
(1)
Salinity control:
The foramol sediments of the
western Florida shelf situated approximately 25° N in
tropical to subtropical warm waters can be explained
Unexpected grain associations and a few warnings:
Many carbonate environments display a specific
grain association related primarily to water tempera-
ture and associated biota. Nevertheless, unexpected
grain associations are rather common in environments,
where the prevailing temperature would point to a dif-
ferent association.
Plate 107 Skeletal Grain Association of WarmTemperate and Tropical WarmWater Shelf Carbonates
Warm-temperate carbonates originate in a zone between the tropical warm-water zone with mean bottom water
temperatures > 22 °C and the mid- to high-latitude cool-temperate zone with mean temperatures from about 10
to 18 °C. The first zone is aragonite/High-Mg calcite-dominated and characterized by calcareous green algae
and coral reefs, benthic foraminifera, and strong early cementation. The second zone is calcite-dominated and
characterized by abundant bryozoans, bivalves, barnacles, echinids and foraminifera, and only weak cementa-
tion. For the Cenozoic, the boundary between the tropical zone and the warm-temperate zone is commonly
drawn at the occurrence/absence of coral reefs and distribution patterns of
larger foraminifera genera
(Hallock
1986: tropical zone; Halfar et al. 2000: warm-temperate zone. See Sect. 10.2.2). The boundary between the
warm-temperate and the cold-temperate zone is indicated by a marked decrease in biotic diversity and the com-
plete absence of green algae and ooids.
1
Bryozoa-Foraminifera association.
Many Miocene shallow-marine carbonates are characterized by an assemblage of
bryozoans, benthic foraminifera and corallinacean red algae. The thin section exhibits a bryozoan packstone rich in
celleporiform and branching zoaria. Bryozoans (B) are competing with coralline red algae (RA). Other fossils are rotaliid
larger foraminifera (
Heterostegina;
H) and serpulid worms (S;
Ditrupa
). Heterosteginid foraminifera occur both in tropi-
cal and warm-temperate environments. The Heterozoan Association with corallinacean red algae and serpulids points to
warm-temperate
conditions. This is in agreement with the approximate paleolatitude of 45° N. Late Tertiary (Middle
Miocene): Holy Cross Mountains, central Poland.
2
Foraminifera-Bryozoa association.
The floatstone exhibits larger foraminifera considered as light-dependent because of
inferred algal endosymbionts. Orbitoid foraminifera are
Orbitoides apiculata
Schlumberger (O),
Lepidorbitoides socialis
(Leymerie) - L, and
Siderolites
(SI); alveolinids are
Nummufallotia cretacea
(Schlumberger) - N. Other skeletal grains
are bryozoans (B) and serpulids (
Ditrupa
; S). Black grains are nodular corallinacean red algae (RA). The sample comes
from carbonates formed in subtidal areas between rudist reefs. The biotic composition of the Heterozoan Association as
well as the paleolatitudinal position (›30° N) point to warm-water conditions in the
transition zone between tropical and
warm-temperate
regions. Late Cretaceous (Late Maastrichtian): Sierra de Urbasa, Province Navarra, northern Spain.
-> 1: Studencki 1988; 2: Schwentke and Wiedmann 1985
