(exploitation) of manganese nodules are currently being
developed (ISA, 2013b).
The seabed: a source of raw materials for
humankind?
The seabed is already an important source of commodities
for humankind. Sand and gravel as well as oil and gas have
been mined from the sea for decades. Moreover, the
so-called placer deposits of diamonds have been extracted
off the coast of South Africa and Namibia for a long time
in addition to deposits of tin, titanium, and gold along the
coasts of Africa, Asia, and Australia (Cronan, 1992, 2000;
Rona, 2003, 2008). These placer deposits are accumulations of minerals with a high density and chemical resistance to weathering that form along beaches by gravity
settling due to wave or current movement.
Obtaining raw materials from the sea is therefore not a
new practice. Interest is also growing with respect to phosphorite occurrences with projects being considered within
the EEZ of New Zealand, Mexico, Namibia, and the USA.
Marine phosphorites are sedimentary rocks that contain
high concentrations of phosphate and form along continental margins with oceanic upwelling (Burnett and
Riggs, 1990).
Raw materials are not confined to shallow water. Potential mineral resources from the deep sea currently investigated are manganese nodules, cobalt-rich manganese
crusts, as well as massive sulfides (SPC, 2013; Hein
et al., 2013; Fouquet and Lacroix, 2014). Details of the
formation, characteristics, and resource potential of all
these commodities can be found in the respective entries
of this encyclopedia. The raw materials from the deep
sea are commonly described as renewable resources. This
is misleading since, for instance, the metals in manganese
nodules and cobalt-rich ferromanganese crusts take millions of years to accumulate. Even the considerably faster
growing SMS take thousands of years to accumulate to
economically interesting amounts.
SMS, also known as black smoker deposits, are occurrences of metal-bearing minerals that form on and below
the seabed as a consequence of the interaction of seawater
with a heat source (magma) in the sub-seafloor region of
volcanically active oceanic spreading centers and along
volcanic arcs (Hannington et al., 2005). These occurrences are commonly associated with “oasis of life” harboring chemosynthetic faunal communities. By far the
majority of SMS occurrences presently known are small,
3-dimensional bodies that can contain metals such as copper, zinc, gold, and silver. Other trace elements that are
important for a variety of industry uses (Bi, Ga, Ge, In,
Te) can be enriched at certain sites and are commonly considered as possible important by-products. Known SMS
deposits at the seafloor rarely exceed a few million tonnes
of metal (Hannington et al., 2011) with the exception of
the metalliferous muds in the Atlantis II Deep of the Red
Sea, which formed under different conditions and was
estimated to contain 90+ million tonnes of ore (Nawab,
1984). New technologies to explore for inactive sites away
from the ridge axis are being developed in order to investigate the full ocean potential for sulfides (Cathles, 2011;
Hannington, 2011). As a result, there is considerable interest in exploration both within the EEZ of coastal states and
The Area (see below, ECORYS, 2014). The technology
for mining these deposits is currently being built, and first
deep-sea tests were performed by the Japanese in their
coastal waters (Masuda et al., 2014). The Canadian company Nautilus Minerals is constructing deep-sea SMS collectors for its Solwara 1 deposit in the territorial waters of
Papua New Guinea. This site could become the first deepsea mine site for SMS, as a mining license was issued by
the PNG government in 2011. Current planning foresees
the start of mining operations in 2018.
Manganese nodules occur widely on the vast,
sediment-covered abyssal plains at depths of about
4,000–6,500 m. They are mineral concretions made up
largely of manganese and iron that form around a hard
nucleus and incorporate metals from the sediment and seawater. As manganese nodules form directly on the seafloor, these deposits can be regarded as a 2-dimensional
resource. The greatest concentrations of metal-rich nodules occur in the Clarion-Clipperton Zone (CCZ; Hein
and Koschinsky, 2014), which extends from Hawaii to
Mexico. Nodules are also concentrated in the Peru Basin,
near the Cook Islands, and at abyssal depths in the Indian
and Atlantic Oceans. Manganese and iron are the principal
metals in polymetallic nodules, but the metals of greatest
economic interest are nickel, copper, and cobalt that combined can reach between 2.5 and 3 wt% (Hein and
Koschinsky, 2014). In addition, there are enrichments of
other valuable metals, such as molybdenum, vanadium,
titanium, the rare earth elements (REE), and lithium, that
have industrial importance in many high-tech and greentech applications and can possibly be recovered as
by-products once appropriate processing techniques are
developed. The geochemistry of manganese nodules
varies from ocean to ocean, and details are given in the
respective entry of this encyclopedia.
Manganese nodules were explored intensely in the
1970s and 1980s mainly for their potential use as a copper
resource. An estimate of the in situ value of these metals,
published in 1962 by Mero, initiated a “gold rush” mentality that resulted in national exploration programs by
numerous countries. At the same time, this “gold rush”
was also responsible for setting the stage for international
regulations culminating in the development of the United
Nations Convention on the Law of the Sea (UNCLOS).
During this first period of activities, several hundred
tonnes of manganese nodules were collected from the seafloor during several hours of operation showing that mining is, in principle, possible and relatively easy. However,
the step from a few hours of operation to reliable mining
during 250–300 days a year is challenging.
Cobalt-rich ferromanganese crusts form on nearly all
rock surfaces in the ocean that are free of sediment and
are composed of manganese oxides and iron
476
MARINE MINERAL RESOURCES
developed (ISA, 2013b).
The seabed: a source of raw materials for
humankind?
The seabed is already an important source of commodities
for humankind. Sand and gravel as well as oil and gas have
been mined from the sea for decades. Moreover, the
so-called placer deposits of diamonds have been extracted
off the coast of South Africa and Namibia for a long time
in addition to deposits of tin, titanium, and gold along the
coasts of Africa, Asia, and Australia (Cronan, 1992, 2000;
Rona, 2003, 2008). These placer deposits are accumulations of minerals with a high density and chemical resistance to weathering that form along beaches by gravity
settling due to wave or current movement.
Obtaining raw materials from the sea is therefore not a
new practice. Interest is also growing with respect to phosphorite occurrences with projects being considered within
the EEZ of New Zealand, Mexico, Namibia, and the USA.
Marine phosphorites are sedimentary rocks that contain
high concentrations of phosphate and form along continental margins with oceanic upwelling (Burnett and
Riggs, 1990).
Raw materials are not confined to shallow water. Potential mineral resources from the deep sea currently investigated are manganese nodules, cobalt-rich manganese
crusts, as well as massive sulfides (SPC, 2013; Hein
et al., 2013; Fouquet and Lacroix, 2014). Details of the
formation, characteristics, and resource potential of all
these commodities can be found in the respective entries
of this encyclopedia. The raw materials from the deep
sea are commonly described as renewable resources. This
is misleading since, for instance, the metals in manganese
nodules and cobalt-rich ferromanganese crusts take millions of years to accumulate. Even the considerably faster
growing SMS take thousands of years to accumulate to
economically interesting amounts.
SMS, also known as black smoker deposits, are occurrences of metal-bearing minerals that form on and below
the seabed as a consequence of the interaction of seawater
with a heat source (magma) in the sub-seafloor region of
volcanically active oceanic spreading centers and along
volcanic arcs (Hannington et al., 2005). These occurrences are commonly associated with “oasis of life” harboring chemosynthetic faunal communities. By far the
majority of SMS occurrences presently known are small,
3-dimensional bodies that can contain metals such as copper, zinc, gold, and silver. Other trace elements that are
important for a variety of industry uses (Bi, Ga, Ge, In,
Te) can be enriched at certain sites and are commonly considered as possible important by-products. Known SMS
deposits at the seafloor rarely exceed a few million tonnes
of metal (Hannington et al., 2011) with the exception of
the metalliferous muds in the Atlantis II Deep of the Red
Sea, which formed under different conditions and was
estimated to contain 90+ million tonnes of ore (Nawab,
1984). New technologies to explore for inactive sites away
from the ridge axis are being developed in order to investigate the full ocean potential for sulfides (Cathles, 2011;
Hannington, 2011). As a result, there is considerable interest in exploration both within the EEZ of coastal states and
The Area (see below, ECORYS, 2014). The technology
for mining these deposits is currently being built, and first
deep-sea tests were performed by the Japanese in their
coastal waters (Masuda et al., 2014). The Canadian company Nautilus Minerals is constructing deep-sea SMS collectors for its Solwara 1 deposit in the territorial waters of
Papua New Guinea. This site could become the first deepsea mine site for SMS, as a mining license was issued by
the PNG government in 2011. Current planning foresees
the start of mining operations in 2018.
Manganese nodules occur widely on the vast,
sediment-covered abyssal plains at depths of about
4,000–6,500 m. They are mineral concretions made up
largely of manganese and iron that form around a hard
nucleus and incorporate metals from the sediment and seawater. As manganese nodules form directly on the seafloor, these deposits can be regarded as a 2-dimensional
resource. The greatest concentrations of metal-rich nodules occur in the Clarion-Clipperton Zone (CCZ; Hein
and Koschinsky, 2014), which extends from Hawaii to
Mexico. Nodules are also concentrated in the Peru Basin,
near the Cook Islands, and at abyssal depths in the Indian
and Atlantic Oceans. Manganese and iron are the principal
metals in polymetallic nodules, but the metals of greatest
economic interest are nickel, copper, and cobalt that combined can reach between 2.5 and 3 wt% (Hein and
Koschinsky, 2014). In addition, there are enrichments of
other valuable metals, such as molybdenum, vanadium,
titanium, the rare earth elements (REE), and lithium, that
have industrial importance in many high-tech and greentech applications and can possibly be recovered as
by-products once appropriate processing techniques are
developed. The geochemistry of manganese nodules
varies from ocean to ocean, and details are given in the
respective entry of this encyclopedia.
Manganese nodules were explored intensely in the
1970s and 1980s mainly for their potential use as a copper
resource. An estimate of the in situ value of these metals,
published in 1962 by Mero, initiated a “gold rush” mentality that resulted in national exploration programs by
numerous countries. At the same time, this “gold rush”
was also responsible for setting the stage for international
regulations culminating in the development of the United
Nations Convention on the Law of the Sea (UNCLOS).
During this first period of activities, several hundred
tonnes of manganese nodules were collected from the seafloor during several hours of operation showing that mining is, in principle, possible and relatively easy. However,
the step from a few hours of operation to reliable mining
during 250–300 days a year is challenging.
Cobalt-rich ferromanganese crusts form on nearly all
rock surfaces in the ocean that are free of sediment and
are composed of manganese oxides and iron
476
MARINE MINERAL RESOURCES