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问题：【急求地球的介绍!得是英文!】
答案：↓↓↓ 盛雨的回答： 网友采纳 TheEarth'ssurfaceisveryyoung.Intherelativelyshort(byastronomicalstandards)periodof500,000,000yearsorsoerosionandtectonicprocessesdestroyandrecreatemostoftheEarth'ssurfaceandtherebyeliminatealmostalltracesofearliergeologicsurfacehistory(suchasimpactcraters).ThustheveryearlyhistoryoftheEarthhasmostlybeenerased.TheEarthis4.5to4.6billionyearsold,buttheoldestknownrocksareabout4billionyearsoldandrocksolderthan3billionyearsarerare.Theoldestfossilsoflivingorganismsarelessthan3.9billionyearsold.Thereisnorecordofthecriticalperiodwhenlifewasfirstgettingstarted 71PercentoftheEarth'ssurfaceiscoveredwithwater.Earthistheonlyplanetonwhichwatercanexistinliquidformonthesurface(thoughtheremaybeliquidethaneormethaneonTitan'ssurfaceandliquidwaterbeneaththesurfaceofEuropa).Liquidwateris,ofcourse,essentialforlifeasweknowit.TheheatcapacityoftheoceansisalsoveryimportantinkeepingtheEarth'stemperaturerelativelystable.LiquidwaterisalsoresponsibleformostoftheerosionandweatheringoftheEarth'scontinents,aprocessuniqueinthesolarsystemtoday(thoughitmayhaveoccurredonMarsinthepast). | 
