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1、TheGreyBeginningsRachelCarsonBeginningsareapttobeshadowy,andsoitiswiththebeginningsofthatgreatmotheroflife,thesea.Manypeoplehavedebatedhowandwhentheearthgotitsocean,anditisnotsurprisingthattheirexplanationsdonotalwaysagree.Fortheplainandinescapabletruthisthat
2、noonewastheretosee,andintheabsenceofeyewitnessaccountsthereisboundtobeacertainamountofdisagreement.SoifItellherethestoryofhowtheyoungplanetEarthacquiredanocean,itmustbeastorypiecedtogetherfrommanysourcesandcontainingwholechaptersthedetailsofwhichwecanonlyimag
3、ine.Thestoryisfoundedonthetestimonyoftheearth’smostancientrocks,whichwereyoungwhentheearthwasyoung;onotherevidencewrittenonthefaceoftheearth’ssatellite,themoon;andonhintscontainedinthehistoryofthesunandthewholeuniverseofstar-filledspace.Foralthoughnomanwasthe
4、retowitnessthiscosmicbirth,thestarsandthemoonandtherockswerethere,and,indeed,hadmuchtodowiththefactthatthereisanocean.开端总是隐约模糊。大海生命之伟大母亲的起源，也是如此。大海在地球上如何产生又是何时出现，人们对此争论不休，其解释莫衷一是，却也不足为怪。因为一个显而易见且不可忽视的事实是，无人亲眼看到，而既然并无目击者的叙述，产生许多分歧在所难免。所以，如果我在此讲述年轻星球即地球如何获得海洋的故
5、事，这一定是个从各种资料中汲取信息拼凑出的故事，它所包含的全部章节中的细节我们只能去想象。该故事有如下基础：地球上最古老的岩石的证明，岩石年纪尚轻时地球也值青年；在地球的存留的卫星即月球上的证明，以及蕴含在月亮史和布满繁星的宇宙史的线索。因为尽管无人目睹宇宙的诞生，星星、月亮和岩石却切实存在，事实上，它们还与海洋的诞生息息相关。TheeventsofwhichIwritemusthaveoccurredsomewhatmorethan2billionyearsago.Asnearlyassciencecantel
6、lthatistheapproximateageoftheearth,andtheoceanmustbeverynearlyasold.我所描述的这些事件大约发生在二十亿年前。根据科学做出的最为贴切的解释，这接近地球的年龄，而海洋也经历了差不多同样多的年岁。Thenewearth,freshlytornfromitsparentsun,wasaballofwhirlinggases,intenselyhot,rushingthroughtheblackspacesoftheuniverseonapathandat
7、aspeedcontrolledbyimmenseforces.Graduallytheballofflaminggasescooled.Thegasesbegantoliquefy,andEarthbecameamoltenmass.Thematerialsofthismasseventuallybecamesortedoutinadefinitepattern:theheaviestinthecentre,thelessheavysurroundingthem,andtheleastheavyformingt
8、heouterrim.Thisisthepatternwhichpersiststoday—acentralsphereofmolteniron,verynearlyashotasitwastwobillionyearsago,anintermediatesphereofsemiplasticbasalt,andahardoutershell,relativelyquit
