Inner Core- is a solid iron which is surrounded by the outer core
Outer core- dense, molten, fluid metallic-iron core, which surrounds the
Asthenosphere- The region of the upper mantle just below the lithosphere;
the least rigid portion of Earths interior and known as the plastic
layer, flowing very slowly under extreme heat and pressure.
Granite-a coarse-grained (slow cooling) intrusive igneous rock of 25%
quartz and more than 50% potassium and sodium feldspars; characterized as
the continental crust.
Basalt-a common extrusive ingenious rock, fine-grained, comprising the
bulk of the ocean-floor crust, lava flow, and volcanic forms; gabbro is
its intrusive form.
Isostasy- a state
of equilibrium in the earths crust formed by the
interplay between portions of the lithosphere and the asthenosphere and
the principle of buoyancy. The crust depresses under weight and recovers
with its removal, for example, the melting of glacier ice. The uplift is
known as isostatic rebound.
a polarity change in earths magnetic field. With
uneven regularity, the magnetic field fades to zero, then returns to full
strength but with the magnetic poles reversed. Reversals have been
recorded 9 times the past 4 million years.
a general term characterizing the vast cycling that
proceeds in the lithosphere. It encompasses the hydrologic cycle,
tectonic cycle, and rock cycle.
a model representing the interrelationships among the three
rock-forming processes: igneous, sedimentary, and metamorphic; shows how
each can be transformed into another rock type.
an assemblage of minerals bound together, or sometimes a mass of a
an element or combination of elements that forms an inorganic
natural compound; described by a specific formula and crystal structure.
One of the basic rock types; it has solidified and
crystallized from a hot molten state (either lava or magma).
one of three basic rock types; formed from the
compactions, cementation, and hardening of sediments derived from other
one of three basic rock types, it is existing igneous
and sedimentary rock that has undergone profound physical and chemical
changes under increased pressure and temperature. Constituent mineral
structures may exhibit foliated or non-foliated textures.
molten rock from beneath earths surface; fluid, gaseous, under
extreme pressure, and either intruded into existing country rock or
extruded onto the surface as lava.
magma that issues from volcanic activity onto the surface; the
extrusive rock that results when magma solidified.