自然地理学专业英语
自然地理学专业英语
自然地理学专业英语
Ｌecture１
INTRODＵCＴIONTOＥＡRTH
MajｏrCｏncｅpt(I)
Thepｌaｎｅtsiｎｏursoｌaｒsystｅｍ,iｎclｕdｉnｇEａｒｔh,beｇaｎｔoformoutｏfarｏtａtingdｉskofｇasａnｄdustａbouｔ4、6biｌlionyｅaｒsago、
Relatedorsupportingcｏnｃepts:
Ｔhｅｐrｅseｎtvieｗofthebegiｎninｇofthesoｌａｒｓｙstemｓuｇgeｓtsthaｔａclouｄofgasandｄｕsｔwaｓｆlattenedintoａdiｓkbyroｔａtiｏｎ、Tｈeｄeｎｓｉtｙoftｈematｔｅｒinｔhｅdisｋwａsgreａｔｅｓｔatｉtsceｎteｒａnddecrｅasedtoｗarｄtheedｇｅs、
Tｈesunfｏrmeｄatｔhecｅnterofｔhediskwheretｈeｔｅmｐeratuｒeｗashigｈestaｎdtheplanetsformedａtgrｅaｔｅrdiｓtanｃeｓawayｆrｏmtｈeceｎｔeｒ、
Thepｏsitiｏｎｓoftheplanｅｔｓdｉｆｆerbｅｃａuｓeofａｎaturalｓortinｇofeｌemｅｎtsintheclｏｕdｗｉｔｈdistaｎcefｒｏmｔｈeｃenter、
ThｅtemｐｅratureｏfｔｈｅｅａｒlyEａrtｈwasprobａｂｌyquitehighdｕeｔo:
a、ｔheｇravｉtatｉonａlcaptureｏｆpａrtｉclｅsthaｔｒeleasedheaｔonimpact,
ｂ、ｔｈeincreasedprｅssｕreｏｎｔheinteriorofｔｈepｌaneｔａsｉｔcｏntinuedｔoｇrow,ａnｄ
c、thecapturｅofrａｄioaｃtiveeｌeｍeｎtsｔhatgａveofｆhｅａtwｈeｎtheｙdｅcａyｅd、
Duｒingｔhefirsｔｆeｗhｕndｒeｄmiｌｌiｏnyears,theiｎteｒnａltｅmperaｔurｅrｏsｅhigｈenoughｔomelｔironandnｉckeｌ、Ｔｈeseheavymetalssanｋtoformthｅcoreofthepｌanｅtaｎdｄisｐlaｃedlighｔermateｒialｔｈａtｒosetoｆorｍcｈemicallyｄｉffeｒeｎtiａtｅdsheｌls、
MajｏｒCｏncｅpt(IＩ)
Earｔh’sｏceansoriginatedearｌyinｔheplanet’shistoｒy、Ｔheｒearetwｏproｐosｅｄsｏurcｅsofｔｈewaterintｈeoceaｎｓ、
Rｅlaｔｅdorsuｐｐortｉngｃｏｎcｅpts:
Ｔｈｅoldesｔsedimenｔａrｙrｏｃｋｓfoundthatrｅquｉreｄwａｔerfｏrｔｈeirfｏｒmaｔionare3、9bｉllｉonyｅarｓolｄ、ThissuggesｔsｔｈattherｅareｂeeｎoceansonEａｒtｈfoｒroughly４billiｏnyears、
TrａｄiｔionaｌlyscientｉstshavebeｌｉeｖedｔhatthewａterintheoceansandatmoｓphereｏriginatedｉｎEａｒth’sｍａntleanｄwasbｒougｈｔtothesuｒfaｃebyvolｃanism、
Mosｔmagｍascontａｉnfrｏｍ1%ｔｏ5%dissoｌｖedgasbyｗeigｈt,mｏｓtｏfwhｉchiswatervapoｒ、
Ifｗｅaｓsumeｔhattheｃurｒeｎtratｅｏｆｒeleaｓｅofwaｔeｒｖapｏｒｉnvｏｌcaniｃer