Physical Geography Chapter 11

A depiction of eras, periods, and epochs that span Earth's history; Shows both the sequence of rock strata and their absolute dates, as determined by methods such as radioactive isotopic dating.

An assumption that physical processes active in the environment today are operating at the same pace and intensity that has characterized them throughout geological time; proposed by Hutton and Lyell.

The shock wave sent through the planet by an earthquake or underground nuclear test. transmission varies according to temperature and the density of varies layers within the planet; provides indirect diagnostics evidence of Earth's internal structure.

The deepest in er portion of Earth, representing one-third of it is entire mass; differentiated into toe zones - a solid iron inner core surrounded by a dense , molten, fluid metallic- iron outer core.

A polarity change in Earth's 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 during the past 4 million years.

An area within the planet representing about 80% of Earth's total volume, with densities increasing with depth and averaging 4.5 g/cm; occurs between the core and the crust ; is rich in iron and magnesium oxides and silicates.

Region of the upper mantle just below the lithosphere; the least rigid portion of Earth's interior and known as the plastic layer; flowing very slowly under extreme heat ans pressure.

The boundary between the Crust and the rest of the lithospheric upper mantle; named for the Yugoslavian seismologist Mohorovicic; a Zone of sharp material and density contrasts; also known as the MOHO

A coarse grained intrusive igneous rock characteristic of the continental crust.

A common extrusive igneous rock, fine - grained, comprising the bilk of the ocean-floor crust, lava flows, and volcanic forms; gabbro is its intrusive form.

A state of equilibrium in earth's crust formed by the interplay between portions of the lithosphere and the asthenoshpere and the principal of buoyancy.

A general term characterizing the vast cycling that proceeds inthe lithosphere. It encompasses the ydrologic cycle, tectonic cyle, and rock cycle.

An element or combo of elements that forms an inorganic natural compund; described by a specific formula and crystal structure

One of the basic rock types; it has solidified and crystallized from a hot molten state.

A mass of intrusive igneous rock that has cooled slowly in the crust; forms in any size or shape. The largest partially exposed pluton os a batholith.