大學(xué)新概念英語(yǔ)閱讀一

1、大學(xué)新概念英語(yǔ)閱讀（一）【篇一】PlateTectonicsandSea-floorSpreadingThetheoryofplatetectonicsdescribesthemotionsofthelithosphere,thecomparativelyrigidouterlayeroftheEarththatincludesallthecrustandpartoftheunderlyingmantle.Thelithosphereisdividedintoafewdozenplatesofvarioussizesandshapes,ingeneraltheplatesareinmotion

2、withrespecttooneanother.Amid-oceanridgeisaboundarybetweenplateswherenewlithosphericmaterialisinjectedfrombelow.Astheplatesdivergefromamid-oceanridgetheyslideonamoreyieldinglayeratthebaseofthelithosphere.SincethesizeoftheEarthisessentiallyconstant,newlithospherecanbecreatedatthemid-oceanridgesonlyifa

3、nequalamountoflithosphericmaterialisconsumedelsewhere.Thesiteofthisdestructionisanotherkindofplateboundaryasubductionzone.Thereoneplatedivesundertheedgeofanotherandisreincorporatedintothemantle.Bothkindsofplateboundaryareassociatedwithfaultsystems,earthquakesandvolcanism,butthekindsofgeologicactivit

4、yobservedatthetwoboundariesarequitedifferent.Theideaofsea-floorspreadingactuallyprecededthetheoryofplatetectonics.Initsoriginalversion,intheearly1960's,itdescribedthecreationanddestructionoftheoceanfloor,butitdidnotspecifyrigidlithosphericplates.Thehypothesiswassubstantiatedsoonafterwardbythedis

5、coverythatperiodicreversalsoftheEarth'smagneticfieldarerecordedintheoceaniccrust.Asmagmarisesunderthemid-oceanridge,ferromagneticmineralsinthemagmabecomemagnetizedinthedirectionofthegeomagneticfield.Whenthemagmacoolsandsolidifies,thedirectionandthepolarityofthefieldarepreservedinthemagnetizedvol

6、canicrock.Reversalsofthefieldgiverisetoaseriesofmagneticstripesrunningparalleltotheaxisoftherift.Theoceaniccrustthusservesasamagnetictaperecordingofthehistoryofthegeomagneticfieldthatcanbedatedindependently;thewidthofthestripesindicatestherateofthesea-floorspreading.板塊結(jié)構(gòu)與海床擴(kuò)展板塊結(jié)構(gòu)理論描述巖石圈的運(yùn)動(dòng)。巖石圈是相對(duì)堅(jiān)硬的

7、地球外層，包括全部地殼和部分地幔。巖石圈被劃分為幾十個(gè)大小不同形狀各異的板塊，一般來(lái)說(shuō)這些板塊都處于相對(duì)運(yùn)動(dòng)之中。一道中海脊是板塊之間的邊界，在那里新的巖石圈的物質(zhì)從下部注入。當(dāng)板塊從中海脊脫離時(shí)，它們滑向在巖石圈基部較易變形的地層上。因?yàn)榈厍虻拇笮”举|(zhì)上是不變的，只有同等數(shù)量的巖石圈物質(zhì)在其它地方被吞沒(méi)，新的巖石圈才能生成。銷(xiāo)毀舊巖石圈的地方形成另外一種板塊邊界：一塊潛沒(méi)的區(qū)域。在這里，一塊板塊潛沒(méi)到另一板塊的邊緣之下并結(jié)合入地幔之中。兩種板塊邊界均與地層系統(tǒng)、地震以及火山活動(dòng)相關(guān)，但在兩種邊界處觀察到的諸般地質(zhì)活動(dòng)卻迥然不同。海床擴(kuò)展說(shuō)實(shí)際上早于板塊結(jié)構(gòu)理論。在20世紀(jì)60年代它的理論雛形

8、中，描述了海底的生成和毀滅，但沒(méi)有詳細(xì)介紹堅(jiān)硬的巖石圈板塊。這個(gè)假定不久之后為發(fā)現(xiàn)所證實(shí)。該發(fā)現(xiàn)表明地球磁場(chǎng)周期性的逆轉(zhuǎn)被記錄在海洋地殼中。當(dāng)巖漿從中海脊下涌起的時(shí)候，巖漿中的磁鐵礦物質(zhì)按地磁場(chǎng)的方向被磁化。巖漿冷卻并凝固下來(lái)后，地磁場(chǎng)的方向和磁極被保留在磁化了的火山巖中。磁場(chǎng)的逆轉(zhuǎn)形成一系列與斷層軸線平行的條形磁區(qū)。這樣海洋殼就扮演了磁帶的角色，記錄下能夠鑒定時(shí)間的地磁場(chǎng)的歷史。條形磁區(qū)的寬度表明了海底擴(kuò)展的速度?！酒縊ilRefiningAnimportantnewindustry,oilrefining,grewaftertheCivilwar.Crudeoil,orpetroleu

9、madark,thickoozefromtheearthhadbeenknownforhundredsofyears,butlittleusehadeverbeenmadeofit.Inthe1850sSamuelM.Kier,amanufacturerinwesternPennsylvania,begancollectingtheoilfromlocalseepagesandrefiningitintokerosene.Refining,likesmelting,isaprocessofremovingimpuritiesfromarawmaterial.Kerosenewasusedtol

10、ightlamps.Itwasacheapsubstituteforwhaleoil,whichwasbecominghardertoget.Soontherewasalargedemandforkerosene.Peoplebegantosearchfornewsuppliesofpetroleum.ThefirstoilwellwasdrilledbyE.L.Drake,aretiredrailroadconductor.In1859hebegandrillinginTitusville,Pennsylvania.Thewholeventureseemedsoimpracticalandf

11、oolishthatonlookerscalledit"DrakesFolly".Butwhenhehaddrilleddownabout70feet(21meters),Drakestruckoil.Hiswellbegantoyield20barrelsofcrudeoiladay.NewsofDrakessuccessbroughtoilprospectorstothescene.Bytheearly1860'sthesewildcattersweredrillingfor"blackgold"alloverwesternPennsylva

12、nia.TheboomrivaledtheCaliforniagoldrushof1848initsexcitementandWildWestatmosphere.Anditbroughtfarmorewealthtotheprospectorsthananygoldrush.Crudeoilcouldberefinedintomanyproducts.Forsomeyearskerosenecontinuedtobetheprincipalone.Itwassoldingrocerystoresanddoor-to-door.Inthe1880srefinerslearnedhowtomak

13、eotherpetroleumproductssuchaswaxesandlubricatingoils.Petroleumwasnotthenusedtomakegasolineorheatingoil.【篇四】譯文煉油一種重要的新興工業(yè)一一煉油業(yè)在國(guó)內(nèi)戰(zhàn)爭(zhēng)后成長(zhǎng)起來(lái)。未加工的石油，或原油一一一種深色的地下的稠漿一一數(shù)百年來(lái)一直為大眾所知，但是人們卻很少使用過(guò)它。在十九世紀(jì)五十年代，薩繆爾M科爾，賓西法尼亞西部的一位制造商，開(kāi)始從當(dāng)?shù)氐囊绯鑫镏惺占筒⑺鼰挸擅河汀Ｅc冶煉礦石一樣，石油提煉是一個(gè)從未加工的原料中除去雜質(zhì)的過(guò)程。煤油被用來(lái)點(diǎn)燈。它是鯨油的一種便宜的替代品，而鯨油正變得越來(lái)越難以獲得。不久就產(chǎn)生了對(duì)煤油的大量需求。人們開(kāi)始尋找新的石油供應(yīng)。第一口油井為EL瑞克，一個(gè)退休的火車(chē)檢票員所鉆得。1859年他開(kāi)始在賓西法尼亞的泰特斯維爾鉆井。整個(gè)的這項(xiàng)冒險(xiǎn)事業(yè)看起來(lái)是如此不現(xiàn)實(shí)和愚蠢以致旁觀者稱(chēng)之為“鴨子的蠢行”。（譯者注：DrakesFolly,drake在這里意含雙關(guān)，即指瑞克的名字，又指該詞的本義即鴨子。）但當(dāng)瑞克往下鉆至70英尺（21米）的時(shí)候，他發(fā)現(xiàn)了石油。他的油井從此每天生產(chǎn)20桶原油。瑞