GeophysicsisthephysicsoftheEarth.CentraltotheEarthSciencestoday,itencompassesareassuchasseismology,volcanism,platetectonics,gravitationalanomalies,andtheEarth’smagneticfield(presentandpast,ascapturedinrocks),allofwhichgivecluestoboththestructureandtheworkingoftheEarth.InthisVeryShortIntroduction,WilliamLowriedescribestheinternalandexternalprocessesthataffecttheplanet,aswellastheprinciplesandmethodsofgeophysicsusedtoinvestigatethem.HeexplainshowanalysisoftheseismicwavesproducedinearthquakesrevealstheinternalstructureoftheEarth.GeophysicistshaveestablishedthatthegreatestsourceofenergypoweringgeologicalprocessesistheEarth’sinternalheat.DeepinsidetheEarth,thetemperatureishighenoughtoproduceafluidoutercoreofmolteniron.ItisthemotioninthismoltenironlayerthatproducestheEarth’smagneticfield,whichshieldstheplanetagainstharmfulradiationfromtheSunandouterspace,andthusmakestheplanethabitable.Lowriedescribeshowthemagneticfieldalsomagnetizesrocksduringtheirformation,leavingapermanentrecordoftheancientfieldanditsdirectionthatgeophysicistshavelearnedtousetointerpretpastmotionsofthecontinentsandtectonicplates.FromanalyzesofEarth’sdeepestinteriortomeasurementsmadefromEarth-orbitingsatellites,Lowrieshowshowgeophysicalexplorationisvitallyimportantinthesearchformineralresources,andemphasizesourneedtounderstandthehistoryofourplanetandtheprocessesthatgovernitscontinuingevolution.ABOUTTHESERIES:TheVeryShortIntroductionsseriesfromOxfordUniversityPresscontainshundredsoftitlesinalmosteverysubjectarea.Thesepocket-sizedbooksaretheperfectwaytogetaheadinanewsubjectquickly.Ourexpertauthorscombinefacts,analysis,perspective,newideas,andenthusiasmtomakeinterestingandchallengingtopicshighlyreadable.
