temperature hydrothermal alteration of ash within
subaerial volcanoes that is periodically deposited in
the ocean by explosive volcanism. Nontronite and
iron-montmorillinite have also been suggested to
form at seafloor temperatures by reaction of
hydrothermally derived iron oxides with biogenic
silica. One of the difficulties in assigning a precise
origin to this mineral class is the possibility of
physical admixtures of truly authigenic iron-rich
smectites with more aluminum-rich smectites
derived from the continents (Figure 10).
Glossary
Aluminosilicate A silicate containing aluminum in
coordination with oxyhydroxides and/or in
substitution for silicon in SiO 4 tetrahedra.
Authigenesis New origin. Process of formation of
new minerals in place.
Detrital Formed from detritus, usually from rocks,
minerals, or sediments from elsewhere than the
depositional site.
Diagenesis Changed origin. Recombination or
rearrangement of a mineral that results in a new
mineral, usually postdepositionally.
Hemipelagic Deep-sea sediment that accumulates
near the continental margin, so that the sediment
contains abundant continentally derived material
and rates of sedimentation are high.
Hypersaline Excessive salinity, much greater than
the normal salinity of sea water.
Metalliferous Metal bearing, usually enriched
toward economic extraction of the metals.
Metastable State of a phase that is stable toward
small disturbance, but is capable of reaction if
sufficiently disturbed.
Pedogenesis Soil origin. Mineral formation within
the soil.
Pelagic Open ocean environment. A marine
sediment with that fraction derived from the
continents indicating deposition from a dilute
suspension distributed throughout deep-sea water.
Phyllosilicate Layered or sheet silicate mineral,
formed by sharing three of the four oxygens in
neighboring silicon tetrahedra.
Plankton Aquatic organisms that drift, or swim
weakly. Can be either plants (phytoplankton) or
animals (zooplankton).
Redox Abbreviation for reduction–oxidation,
usually expressed as a potential.
Seamount Underwater mountain, 1000 m or higher
elevation from seafloor base. Morphology may be
peaked or flat-topped, with the latter called guyot.
Suboxic Condition lacking free oxygen, but not
extremely reducing.
Zeolite Any of the minerals of the zeolite group.
Aluminosilicate minerals with an open framework
structure that allows for easily reversible
hydration, gas adsorption, and either cation or
anion exchange.
See also
Clay Mineralogy. Hydrothermal Vent Deposits.
Platinum Group Elements and their Isotopes in
the Ocean. Pore Water Chemistry. Rare Earth
Elements and their Isotopes in the Ocean. River
Inputs. Tracers of Ocean Productivity. Transition
Metals and Heavy Metal Speciation. UraniumThorium Decay Series in the Oceans Overview.
Further Reading
Bentor YK (ed.) (1980) Marine Phosphorites; a Symposium.
Oklahoma: SEPM Special Publication no. 29.
Burns RG and Burns VM (1981) Authigenic oxides. The
Sea, vol. 7, pp. 875--914. New York: Wiley.
Chamley H (ed.) (1989) Clay Sedimentology. Berlin:
Springer-Verlag.
Cronan DS (1974) Authigenic minerals in deep-sea
sediments. In: Goldberg ED (ed.) The Sea, vol. 5,
pp. 491--525. New York: Wiley.
Cronan DS (ed.) (1980) Underwater Minerals. London:
Academic Press.
Cronan DS (ed.) (2000) Handbook of Marine Mineral
Deposits. Boca Raton, FL: CRC Press.
Glasby GP (ed.) (1977) Marine Manganese Deposits.
Elsevier Oceanography Series. Amsterdam: Elsevier.
Glenn CR, Pre ´vot-Lucas L, and Lucas J (eds.) (2000)
Marine Authigenesis: from Global to Microbial.
Oklahoma: SEPM Special publication no. 66.
Halbach P, Friedrich G, and von Stackelberg U (eds.)
(1988) The Manganese Nodule Belt of the Pacific
Ocean: Geological Environment, Nodule Formation,
and Mining Aspects. Stuttgart: F. Enke Verlag.
Kastner M (1981) Authigenic silicates in deep-sea
sediments: formation and diagenesis. In: Emiliani C
(ed.) The Sea, vol. 7, pp. 915--980. New York: Wiley.
Manheim FT (1986) Marine cobalt resources. Science 232:
600--608.
Margolis SV and Burns RG (1976) Pacific deep-sea
manganese nodules: their distribution, composition,
and origin. Annual Review of Earth and Planetary
Science 4: 229--263.
AUTHIGENIC DEPOSITS 335
subaerial volcanoes that is periodically deposited in
the ocean by explosive volcanism. Nontronite and
iron-montmorillinite have also been suggested to
form at seafloor temperatures by reaction of
hydrothermally derived iron oxides with biogenic
silica. One of the difficulties in assigning a precise
origin to this mineral class is the possibility of
physical admixtures of truly authigenic iron-rich
smectites with more aluminum-rich smectites
derived from the continents (Figure 10).
Glossary
Aluminosilicate A silicate containing aluminum in
coordination with oxyhydroxides and/or in
substitution for silicon in SiO 4 tetrahedra.
Authigenesis New origin. Process of formation of
new minerals in place.
Detrital Formed from detritus, usually from rocks,
minerals, or sediments from elsewhere than the
depositional site.
Diagenesis Changed origin. Recombination or
rearrangement of a mineral that results in a new
mineral, usually postdepositionally.
Hemipelagic Deep-sea sediment that accumulates
near the continental margin, so that the sediment
contains abundant continentally derived material
and rates of sedimentation are high.
Hypersaline Excessive salinity, much greater than
the normal salinity of sea water.
Metalliferous Metal bearing, usually enriched
toward economic extraction of the metals.
Metastable State of a phase that is stable toward
small disturbance, but is capable of reaction if
sufficiently disturbed.
Pedogenesis Soil origin. Mineral formation within
the soil.
Pelagic Open ocean environment. A marine
sediment with that fraction derived from the
continents indicating deposition from a dilute
suspension distributed throughout deep-sea water.
Phyllosilicate Layered or sheet silicate mineral,
formed by sharing three of the four oxygens in
neighboring silicon tetrahedra.
Plankton Aquatic organisms that drift, or swim
weakly. Can be either plants (phytoplankton) or
animals (zooplankton).
Redox Abbreviation for reduction–oxidation,
usually expressed as a potential.
Seamount Underwater mountain, 1000 m or higher
elevation from seafloor base. Morphology may be
peaked or flat-topped, with the latter called guyot.
Suboxic Condition lacking free oxygen, but not
extremely reducing.
Zeolite Any of the minerals of the zeolite group.
Aluminosilicate minerals with an open framework
structure that allows for easily reversible
hydration, gas adsorption, and either cation or
anion exchange.
See also
Clay Mineralogy. Hydrothermal Vent Deposits.
Platinum Group Elements and their Isotopes in
the Ocean. Pore Water Chemistry. Rare Earth
Elements and their Isotopes in the Ocean. River
Inputs. Tracers of Ocean Productivity. Transition
Metals and Heavy Metal Speciation. UraniumThorium Decay Series in the Oceans Overview.
Further Reading
Bentor YK (ed.) (1980) Marine Phosphorites; a Symposium.
Oklahoma: SEPM Special Publication no. 29.
Burns RG and Burns VM (1981) Authigenic oxides. The
Sea, vol. 7, pp. 875--914. New York: Wiley.
Chamley H (ed.) (1989) Clay Sedimentology. Berlin:
Springer-Verlag.
Cronan DS (1974) Authigenic minerals in deep-sea
sediments. In: Goldberg ED (ed.) The Sea, vol. 5,
pp. 491--525. New York: Wiley.
Cronan DS (ed.) (1980) Underwater Minerals. London:
Academic Press.
Cronan DS (ed.) (2000) Handbook of Marine Mineral
Deposits. Boca Raton, FL: CRC Press.
Glasby GP (ed.) (1977) Marine Manganese Deposits.
Elsevier Oceanography Series. Amsterdam: Elsevier.
Glenn CR, Pre ´vot-Lucas L, and Lucas J (eds.) (2000)
Marine Authigenesis: from Global to Microbial.
Oklahoma: SEPM Special publication no. 66.
Halbach P, Friedrich G, and von Stackelberg U (eds.)
(1988) The Manganese Nodule Belt of the Pacific
Ocean: Geological Environment, Nodule Formation,
and Mining Aspects. Stuttgart: F. Enke Verlag.
Kastner M (1981) Authigenic silicates in deep-sea
sediments: formation and diagenesis. In: Emiliani C
(ed.) The Sea, vol. 7, pp. 915--980. New York: Wiley.
Manheim FT (1986) Marine cobalt resources. Science 232:
600--608.
Margolis SV and Burns RG (1976) Pacific deep-sea
manganese nodules: their distribution, composition,
and origin. Annual Review of Earth and Planetary
Science 4: 229--263.
AUTHIGENIC DEPOSITS 335