Birnessite Manganese-bearing mineral containing calcium, potassium and
sodium
Chrysotile Hydrated silicate of aluminum, iron and magnesium associated with
serpentinite
Curie Isotherm Temperature of 550 ± 30 °C that it is assumed to correspond to
the depth at which magma chambers exist
Conchoidal fracture Fracture of solidified flow with a smooth surface
D’’ Layer of the Earth *200 km thick located in the lower mantle directly above
the Mantle-Core boundary
Diabase Intrusive igneous rock having the composition of basalt
Diagenesis Transformation (alteration) of sediment or fragmented debris after its
deposition on the sea floor
Diapir Large intrusion within a pre-existing formation
Ductile Soft-material, not solidified, capable of being deformed
Eon refers to a time scale of half a million years or more
Eclogite Rock composed of garnet and sodium-enriched pyroxene
Fault Is the result of crustal fracturing along which there has been displacement
of the sides of the fault with respect to each other. This displacement is parallel
to the direction of the fracture
Felsic Light-colored silicate minerals such as feldspar, plagioclase
Ferrosilite Component (FeSiO 3 ) of an iron-rich pyroxene mineral group
Fore-arc Region between the subduction zone (trench) and the volcanic arc
Gabbro Coarse-grained intrusive rock made up of olivine, pyroxene and feldspar
Gondwana Single, large continent existing in the Southern Hemisphere during
the Paleozoic period (280 million years ago)
Gossan Iron-bearing hydroxide deposit formed by the oxidation of sulfide
minerals
Hackly Term used to define lava flows having jagged surfaces
Harzburgite Altered and serpentinized peridotite made up of 40–90 % olivine
and pyroxene
Haystacks Conical shaped structures of lava extruded from tubes that are piling
on top of each other. Haystacks are formed from a central orifice similar to a
miniature volcano
Hypersthene A mineral of pyroxene. Silicate of aluminum iron and magnesium
366
Glossary
sodium
Chrysotile Hydrated silicate of aluminum, iron and magnesium associated with
serpentinite
Curie Isotherm Temperature of 550 ± 30 °C that it is assumed to correspond to
the depth at which magma chambers exist
Conchoidal fracture Fracture of solidified flow with a smooth surface
D’’ Layer of the Earth *200 km thick located in the lower mantle directly above
the Mantle-Core boundary
Diabase Intrusive igneous rock having the composition of basalt
Diagenesis Transformation (alteration) of sediment or fragmented debris after its
deposition on the sea floor
Diapir Large intrusion within a pre-existing formation
Ductile Soft-material, not solidified, capable of being deformed
Eon refers to a time scale of half a million years or more
Eclogite Rock composed of garnet and sodium-enriched pyroxene
Fault Is the result of crustal fracturing along which there has been displacement
of the sides of the fault with respect to each other. This displacement is parallel
to the direction of the fracture
Felsic Light-colored silicate minerals such as feldspar, plagioclase
Ferrosilite Component (FeSiO 3 ) of an iron-rich pyroxene mineral group
Fore-arc Region between the subduction zone (trench) and the volcanic arc
Gabbro Coarse-grained intrusive rock made up of olivine, pyroxene and feldspar
Gondwana Single, large continent existing in the Southern Hemisphere during
the Paleozoic period (280 million years ago)
Gossan Iron-bearing hydroxide deposit formed by the oxidation of sulfide
minerals
Hackly Term used to define lava flows having jagged surfaces
Harzburgite Altered and serpentinized peridotite made up of 40–90 % olivine
and pyroxene
Haystacks Conical shaped structures of lava extruded from tubes that are piling
on top of each other. Haystacks are formed from a central orifice similar to a
miniature volcano
Hypersthene A mineral of pyroxene. Silicate of aluminum iron and magnesium
366
Glossary