high enough to prevent most crystal forms of calcium carbonate to dissolve. However, carbon dioxide is produced
when organic matter sediments out of the photic zone
and mineralizes in the deep ocean. The carbon dioxide
reacts with the carbonate ion and forms hydrogen carbonate which thus contributes to the dissolution of carbonates.
Consequently, the sediments at several km depth of the
North Atlantic contain carbonates, while sediments at
1 km in the Pacific Ocean might not.
Bibliography
Dieckmann, G. S., et al., 2008. Calcium carbonate as ikaite crystals
in Antarctic sea ice. Geophysical Research Letters, 35, L08501,
doi:10.1029/2008GL033540.
Ingle, S. E., 1975. Solubility of calcite in the ocean. Marine Chemistry, 3, 301–319.
Mucci, A., 1983. The solubility of calcite and aragonite in seawater
at various salinities, temperatures and 1 atmosphere total pressure. American Journal of Science, 238, 780–799.
Pälike, H., et al., 2012. A Cenozoic record of the equatorial Pacific
carbonate compensation depth. Nature, 488, 609–614,
doi:10.1038/nature11360.
Cross-references
Calcite Compensation Depth (CCD)
Cold Seeps
Marine Microfossils
CARBONATE FACTORIES
John J.G. Reijmer
Department of Sedimentology and Marine Geology,, VU
University Amsterdam, Amsterdam, The Netherlands
Synonyms
Carbonate production systems
Definition
Carbonate factories, or production systems, are benthic
carbonate associations that show variations in their dominant precipitation mode, mineral composition, and depth
range of production as well as growth potential
(Schlager, 2000).
Introduction
The term “carbonate factory” was introduced to define the
narrow depth zone where tropical reefs and detrital carbonates are produced (e.g., Tucker and Wright, 1990;
James and Kendall, 1992; Reading and Levell, 1996).
Based on the carbonate factory principle, Schlager
(2000) proposed a threefold subdivision of the benthic carbonate production systems, with the planktonic carbonate
factory as a fourth system. The latter is traditionally dealt
with in the context of paleo-oceanography. The Schlager
(2000) carbonate factory concept is based on the style of
carbonate precipitation in aquatic realms: (1) abiotic,
(2) biotically induced, or (3) biotically controlled
(Lowenstam, 1981). In the latter category, a distinction
can be made between sunlight-controlled organisms
(phototrophic) and nutrient-controlled organisms
(heterotrophic).
Environmental parameters
A series of environmental parameters steer the different
modes of carbonate precipitation. The abiotic mode is normally encountered in marine and freshwater aquatic settings, although increasing evidence suggests microbes
also play a mediating role in the formation of whitings
(e.g., Yates and Robbins, 1998; Thompson, 2000) and
ooids (Pacton et al., 2012). The differentiation found in
the biotically controlled precipitation mode is directed
through a series of environmental factors that drive environmental variations, the most important factors being:
(1) light, (2) temperature, (3) nutrients, and (4) salinity.
These factors set the boundaries for styles of carbonate
precipitation and sediment production profiles but also
for sediment production and distribution. As a result, the
overall morphological development of the carbonate system relates to the dominance of specific factors:
1. Light. This is considered as one of the most important
environmental controls. The depth of the photic column, light penetration, varies around the present-day
globe with a maximum of almost 150 m for the Pacific
atolls (Schlager, 2005).
The light-saturated zone and euphotic zone not only
regulate the growth forms of corals but most importantly the growth rates of the photosynthetic,
carbonate-secreting benthos (Schlager, 2003).
2. Temperature. More or less equal to light is temperature,
as it regulates the diversity of the biotic association.
Each carbonate-secreting species has its own optimum
growth window along the temperature scale (Lees,
1975).
Ocean circulation patterns and latitudinal positions
relate to the distribution and occurrence of specific
water temperatures and hence determine the distribution of specific organisms across the globe.
3. Nutrients. Nutrient variations play an important role as
high nutrient levels reduce calcification rates, but also
stimulate the development of filamentous algae, bryozoans, and barnacles (e.g., Halfar et al., 2004, 2006;
Reijmer et al., 2012); increase bio-erosion rates
(Chazottes et al., 2008); and may hamper coral recruitment (Smith and Buddemeier, 1992; Atkinson et al.,
1995).
4. Salinity. Coral communities are tolerant to long-term
and short-term salinity variations (Muthiga and
Szmant, 1987). The same holds for Mytilus shells
(Malone and Dodd, 1967) whose calcification rates
are not influenced by salinity thresholds. Algal communities exist that have a greater tolerance for high
salinities, and they occur in large terminal lakes like
80
CARBONATE FACTORIES
when organic matter sediments out of the photic zone
and mineralizes in the deep ocean. The carbon dioxide
reacts with the carbonate ion and forms hydrogen carbonate which thus contributes to the dissolution of carbonates.
Consequently, the sediments at several km depth of the
North Atlantic contain carbonates, while sediments at
1 km in the Pacific Ocean might not.
Bibliography
Dieckmann, G. S., et al., 2008. Calcium carbonate as ikaite crystals
in Antarctic sea ice. Geophysical Research Letters, 35, L08501,
doi:10.1029/2008GL033540.
Ingle, S. E., 1975. Solubility of calcite in the ocean. Marine Chemistry, 3, 301–319.
Mucci, A., 1983. The solubility of calcite and aragonite in seawater
at various salinities, temperatures and 1 atmosphere total pressure. American Journal of Science, 238, 780–799.
Pälike, H., et al., 2012. A Cenozoic record of the equatorial Pacific
carbonate compensation depth. Nature, 488, 609–614,
doi:10.1038/nature11360.
Cross-references
Calcite Compensation Depth (CCD)
Cold Seeps
Marine Microfossils
CARBONATE FACTORIES
John J.G. Reijmer
Department of Sedimentology and Marine Geology,, VU
University Amsterdam, Amsterdam, The Netherlands
Synonyms
Carbonate production systems
Definition
Carbonate factories, or production systems, are benthic
carbonate associations that show variations in their dominant precipitation mode, mineral composition, and depth
range of production as well as growth potential
(Schlager, 2000).
Introduction
The term “carbonate factory” was introduced to define the
narrow depth zone where tropical reefs and detrital carbonates are produced (e.g., Tucker and Wright, 1990;
James and Kendall, 1992; Reading and Levell, 1996).
Based on the carbonate factory principle, Schlager
(2000) proposed a threefold subdivision of the benthic carbonate production systems, with the planktonic carbonate
factory as a fourth system. The latter is traditionally dealt
with in the context of paleo-oceanography. The Schlager
(2000) carbonate factory concept is based on the style of
carbonate precipitation in aquatic realms: (1) abiotic,
(2) biotically induced, or (3) biotically controlled
(Lowenstam, 1981). In the latter category, a distinction
can be made between sunlight-controlled organisms
(phototrophic) and nutrient-controlled organisms
(heterotrophic).
Environmental parameters
A series of environmental parameters steer the different
modes of carbonate precipitation. The abiotic mode is normally encountered in marine and freshwater aquatic settings, although increasing evidence suggests microbes
also play a mediating role in the formation of whitings
(e.g., Yates and Robbins, 1998; Thompson, 2000) and
ooids (Pacton et al., 2012). The differentiation found in
the biotically controlled precipitation mode is directed
through a series of environmental factors that drive environmental variations, the most important factors being:
(1) light, (2) temperature, (3) nutrients, and (4) salinity.
These factors set the boundaries for styles of carbonate
precipitation and sediment production profiles but also
for sediment production and distribution. As a result, the
overall morphological development of the carbonate system relates to the dominance of specific factors:
1. Light. This is considered as one of the most important
environmental controls. The depth of the photic column, light penetration, varies around the present-day
globe with a maximum of almost 150 m for the Pacific
atolls (Schlager, 2005).
The light-saturated zone and euphotic zone not only
regulate the growth forms of corals but most importantly the growth rates of the photosynthetic,
carbonate-secreting benthos (Schlager, 2003).
2. Temperature. More or less equal to light is temperature,
as it regulates the diversity of the biotic association.
Each carbonate-secreting species has its own optimum
growth window along the temperature scale (Lees,
1975).
Ocean circulation patterns and latitudinal positions
relate to the distribution and occurrence of specific
water temperatures and hence determine the distribution of specific organisms across the globe.
3. Nutrients. Nutrient variations play an important role as
high nutrient levels reduce calcification rates, but also
stimulate the development of filamentous algae, bryozoans, and barnacles (e.g., Halfar et al., 2004, 2006;
Reijmer et al., 2012); increase bio-erosion rates
(Chazottes et al., 2008); and may hamper coral recruitment (Smith and Buddemeier, 1992; Atkinson et al.,
1995).
4. Salinity. Coral communities are tolerant to long-term
and short-term salinity variations (Muthiga and
Szmant, 1987). The same holds for Mytilus shells
(Malone and Dodd, 1967) whose calcification rates
are not influenced by salinity thresholds. Algal communities exist that have a greater tolerance for high
salinities, and they occur in large terminal lakes like
80
CARBONATE FACTORIES