Iapetus Ocean
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Iapetus Ocean (syn. Proto-Atlantic Ocean) the sea at about the position of the present Atlantic, named after Iapetus, in Greek mythology the father of Atlas. It
separated the Baltic (N. Europe) plate from the Laurentian (N. America and
Greenland) plate throughout the early Paleozoic. The Iapetus Ocean was
closed when the two plates collided during the late Silurian.
ice when water freezes to ice the latent heat of freezing set free is 334 joule per
gram water. This is practically the same for freshwater and seawater. Because
of its salinity, however, the freezing point of seawater is below DoC. In seawater with a typical salinity of 35 the freezing point is about -l.9 0c. Sea ice consists of a framework of ice crystals encapsulating cells of concentrated seawater; this in contrast to the ice of icebergs, which does not contain seawater.
The structure and mechanical properties of sea ice strongly depend on the
age and evolution of the ice. For the description of sea ice a special terminology has been developed on the basis of its external appearance held characteristic of its way of formation, such as ice slush (a layer of thin floating ice
plates), pancake ice (more or less rounded ice floes), pack ice (cohesive mass
of ice floes), sometimes deformed by external pressure into ridges and hummocks. Large open areas where the ice regularly breaks open because of differential movement are indicated by the Russian name polynya.
ice age -7glacial epoch.
iceberg large piece of glacier detached from an ice sheet (Arctic regions like
Greenland) or from an ice shelf (the Antarctic ice cap). This difference in origin is reflected in their morphology: Greenland icebergs are irregular,
Antarctic icebergs are usually tabular. An iceberg is either freely floating in
the sea or stranded on a shoal. The submarine part of a floating iceberg is
about nine times larger than the visible part. Smaller pieces of icebergs are
called floe-bergs (less than 5 m high) and growlers (almost submerged floebergs). -7sea ice, land ice.
ice cap mass of ice covering a highland area or a flat landmass such as an Arctic
island. Ice caps outrange the underlying topography and are (by definition)
smaller than 50000 km 2 • Compare ice sheet.
ice rafting transport of rock fragments of all sizes on or within floating ice.
-7glaciomarine sediments.
158
Iapetus Ocean (syn. Proto-Atlantic Ocean) the sea at about the position of the present Atlantic, named after Iapetus, in Greek mythology the father of Atlas. It
separated the Baltic (N. Europe) plate from the Laurentian (N. America and
Greenland) plate throughout the early Paleozoic. The Iapetus Ocean was
closed when the two plates collided during the late Silurian.
ice when water freezes to ice the latent heat of freezing set free is 334 joule per
gram water. This is practically the same for freshwater and seawater. Because
of its salinity, however, the freezing point of seawater is below DoC. In seawater with a typical salinity of 35 the freezing point is about -l.9 0c. Sea ice consists of a framework of ice crystals encapsulating cells of concentrated seawater; this in contrast to the ice of icebergs, which does not contain seawater.
The structure and mechanical properties of sea ice strongly depend on the
age and evolution of the ice. For the description of sea ice a special terminology has been developed on the basis of its external appearance held characteristic of its way of formation, such as ice slush (a layer of thin floating ice
plates), pancake ice (more or less rounded ice floes), pack ice (cohesive mass
of ice floes), sometimes deformed by external pressure into ridges and hummocks. Large open areas where the ice regularly breaks open because of differential movement are indicated by the Russian name polynya.
ice age -7glacial epoch.
iceberg large piece of glacier detached from an ice sheet (Arctic regions like
Greenland) or from an ice shelf (the Antarctic ice cap). This difference in origin is reflected in their morphology: Greenland icebergs are irregular,
Antarctic icebergs are usually tabular. An iceberg is either freely floating in
the sea or stranded on a shoal. The submarine part of a floating iceberg is
about nine times larger than the visible part. Smaller pieces of icebergs are
called floe-bergs (less than 5 m high) and growlers (almost submerged floebergs). -7sea ice, land ice.
ice cap mass of ice covering a highland area or a flat landmass such as an Arctic
island. Ice caps outrange the underlying topography and are (by definition)
smaller than 50000 km 2 • Compare ice sheet.
ice rafting transport of rock fragments of all sizes on or within floating ice.
-7glaciomarine sediments.