Plate TectonicsA Brief Overview

The Earths Plateshttp://www.nature.nps.gov/geology/usgsnps/pltec/pltec2.html

Layers of the EarthChemicalPhysicalhttp://www.burkemuseum.org/static/geo_history_wa/The%20Restless%20Earth%20v.2.0.htm

Layers of the Earth and FoodLithosphereChocolate: when its cold, its hard and breaks, but as it warms up it can bend and eventually meltAsthenosphereHoney: its thick and sticky, but it flowsMantleCrumbled cookies: its solid but can move and convectOuter coreMilk: liquidInner corePeach pit: solid

Plate BoundariesStern, R. J., Subduction zones, Rev. Geophys., 40(4), 1012, doi:10.1029/2001RG000108, 2002

Margins: DivergentMid-Ocean RidgesMid Atlantic RidgeContinental RiftsEast African Rift Valleyhttp://www.phschool.com/atschool/phsciexp/internet_activity/cfd-1014_midocean.htmlhttp://www.talktalk.co.uk/reference/encyclopaedia/hutchinson/m0006339.html

Margins: ConvergentOcean-ocean subductionIsland arc: Marianashttp://www.see.leeds.ac.uk/structure/dynamicearth/subduction/cordillera_islandarc.htm

Margins: ConvergentOcean-continent subductionVolcanic arc and mountains: Andeshttp://www.see.leeds.ac.uk/structure/dynamicearth/subduction/cordillera_islandarc.htm

Margins: ConvergentContinent-continent collisionLarge mountain range: Himalayas and Alpshttp://www.unil.ch/igp/page23575_en.html

Margins: TransformMarineTransform faults: Mid Atlantic RidgeTerrestrialStrike-slip faults: San Andreas Faulthttp://geomaps.wr.usgs.gov/archive/socal/geology/inland_empire/socal_faults.html

Evidence for Plate TectonicsFit of the continentsSea floor ages and magnetic anomalies evidence of ocean spreadingPaleontology similar species on now widely separated continentsSeismicity and volcanism concentrated at plate boundaries evidence of oceanic subductionHot spot tracks record movement of plates over fixed hot spotGPS