Kīlauea

Kīlauea

3Dfalse-coloursatelliteimageofKīlauea

Elevation

4,091ft(1,247m)

Location

Hawaii,USA

Range

HawaiianIslands

Coordinates

19°25′N,155°17′W

Type

Shieldvolcano

Volcanic

arc/belt

Hawaiian-Emperorseamountchain

Ageofrock

<

23000

yrs

Lasteruption

2007(currenteruptionbeganin1983)

KīlaueaisanactivevolcanointheHawaiianIslands,oneoffiveshieldvolcanoesthattogetherformtheIslandofHawaii.InHawaiian,thewordkīlaueameans"spewing"or"muchspreading",inreferencetothemountain'sfrequentoutpouringoflava.ItiscurrentlythemostactivevolcanoandoneofthemostvisitedactivevolcanoesonEarth.KīlaueaisthemostrecentofaseriesofvolcanoesthatcreatedtheHawaiianArchipelago,asthePacificPlatemovesovertheHawaiihotspot.

Description

Kīlauea'sabsolutelocationisNorth,West.ItislocatedonHawaiiIsland,Hawaii,intheU.S.ItliesagainstthesoutheastflankofmuchlargerMaunaLoavolcano.MaunaLoa'smassivesizeandelevation(13,677feetor4,169m)isastarkcontrasttoKīlauea,whichrisesonly4,091feet(1,247m)abovesealevel,andthusfromthesummitcalderaappearsasabroadshelfofuplandswellbeneaththelongprofileofoccasionallysnow-cappedMaunaLoa,15miles(24km)distant.

First-timevisitorstoKīlauea,notfamiliarwithhowdifferenttheprofileofashieldvolcanocanbecomparedwithstratovolcanoeslikeMt.Fuji,MountHood,andMountSt.Helens,areusuallyunawaretheyareapproachingthesummitofanactivevolcanoastheymakethedriveupthroughthecloudforestonStateRte.11toHawaiiVolcanoesNationalParkfromHilo—orcomingfromKailua-KonaviaSouthPointacrosstheKaūDesert.FromHilo,thehighwayheadssouthtoKeaau,thenturnsabruptlywestwardtobegintheclimbtotheKīlaueacaldera.Forsome20miles(32km)theroadrunsrelativelystraight,makinga4,000ft(1,200m)ascent.However,mostofthisclimbisactuallyontheheavilyvegetatedflankofMaunaLoa;thecrossingontolavaflowsissuedfromKīlaueaisabout1milewestofGlenwood,18miles(29km)fromHilo.TheMaunaLoaflowsareseveralthousandyearsold;thelightlyvegetatedKīlaueaflowsareonly350to500yearsold.

DrivingfromtheKonaCoast,theimmensesizeoftheBigIslandbecomesapparent:fromKailua-Konaitis98miles(158km)ontheMāmalahoaHighway(StateRte.11)toKīlauea.AfterpassingaroundthesouthernendofMaunaLoa,thehighwayturnsnortheastwardtowardsKīlaueaoncepastthetownofNāālehu.Yet,asfromtheHiloside,thelongclimbfromnearsealeveltothesummitisallontheflankofMaunaLoa.NotuntiltheSulfurBankscarp(thenorthwesternedgeofKīlaueaCaldera),neartheintersectionofCraterRimDriveinHawaiiVolcanoesNationalPark,doestheroadcrossoverontoKīlauea.However,thehighwayparallelsthelineofcontactbetweenthetwovolcanoes—alwayslessthan1miletothesoutheast—fromthevicinityofPunaluuatthecoasttothecalderaatthesummit.

Kaū

Thehighwayroutefromthewest(StateRte.11)isvastlydifferentfromthatseenwhencomingfromHilo.ThehighwayapproachesKīlaueathroughadesertontheleewardslopecalledKaū.Kīlauea'sheightof4000ftissufficienttoforcemostofthemoistureoutoftheimpingingNortheastTrades,leavingKaūintherainshadowofthe"low"mountain.ThisareaisalsotheveryactivesouthwestriftzoneofKīlauea,aprolificashproducer.Windsredistributetheash,causingduststormsanddunesbarrenofmostvegetation.

KīlaueaCalderaandHalemaumauCrater

Halemaumaucrater

HawaiiVolcanoesNationalParkencompassesaportionofKīlauea,andtheparkvisitorcenterislocatednearthemarginofthesummitcaldera,overlookingalargepitcratercalledHalemaumau.Theroughlycircularcalderameasures3x5km(or6x6km,includingtheoutermostringfaults).

Kīlaueaeruptions

SteamplumeasKīlauealavaenterstheocean

EruptionofKilaueain1954

Lavaexplodesasoceanwavescoverlavatubes

AerialviewofPuuōōcrater,Kīlaueatakenon10September2007

EruptionsatKīlaueaoccurprimarilyeitherfromthesummitcalderaoralongeitherofthelengthyEastandSouthwestriftzonesthatextendfromthecalderatothesea.Inrecentdecades,eruptionshavebeencontinuous,withmanyofthelavaflowsreachingtothePacificOceanshore.About90%ofthesurfaceofKīlaueaislavaflowslessthan1,100yearsold;70%ofthesurfaceisyoungerthan600years.

Therewere45eruptionsofKīlaueainthetwentiethcentury.TheMaunaUlueruptionofKīlaueabeganonMay24,1969andendedonJuly22,1974.Atthetime,MaunaUluwasthelongestflankeruptionofanyHawaiianvolcanoinrecordedhistory.Theeruptioncreatedanewvent,coveredmassiveamountsoflandwithlava,andaddednewlandtotheisland.TheMaunaUlueruptionfirststartedasafissurebetweentwopitcraters,āloiandAlae,wheretheMaunaUlushieldwouldeventuallyform.Bothpāhoehoeandaālavaeruptedfromthevolcano.Earlyon,fountainsoflavaburstoutasmuchas540metershigh.Inearly1973,anearthquakeoccurredthatcausedKīlaueatostoperuptingneartheoriginalMaunaUlusiteandinsteaderuptnearthecratersPauahiandHiiaka.However,theeruptionsitesoonreturnedtonormal.The1990lavaflowinparticularwasnotableforbeingdestructiveofproperty.

ThecurrentKīlaueaeruptionbeganinJanuary1983alongtheEastriftzonefromPuuōō-Kūpaianahāandcontinuestoproducelavaflowsthattravel11to12kmfromtheseventstothesea.Thiseruptionhascoveredover117km2oflandonthesouthernflankofKīlaueaandhasbuiltoutintothesea2km2(230hectares)ofnewland.Since1983morethan2.7km3oflavahasbeenerupted,makingthe1983-to-presenteruptionthelargesthistoricallyknownforKīlauea.189structureshavebeendestroyed.Intheearlytomiddle1980sKīlaueawasknownas"TheDrive-byVolcano"becauseanyonecouldridebyandseethelavafountains(someasmuchas1000feetintheair)fromtheircar.

Inthe1990lavaflowthetownsofKalapanaandKaimūweretotallydestroyed,aswereKaimūBay,KalapanaBlackSandBeach,andalargesectionofStateRte.130,whichnowabruptlydead-endsatthelavaflow.WhileKīlaueaisjustlyknownforitslargelynon-explosiveeruptions,ithasadarkersidetoit:ithashadlargeexplosiveeruptionsinthepast.Themostrecentofsuchexplosiveeruptionsoccurredin1924,whenmagmainteractedwithgroundwaterasthelong-standinglavalakeinHalemaumauCraterdrained.Evenlargeroneshaveoccurred,includingonein1790,whichkilledatleastseveraldozenpeople.Eruptioncolumnsareinferredtohavegoneatleastashighas9kmmiles)andevenupto15-20km(9-12miles)inaltitude—muchhigherthanthecruisingaltitudeofairliners.

EruptionsfromKīlaueaalsoareknownforcreatingvog,orvolcanicsmog,whichaffectsmanyareasoftheHawaiianIslands,includingOahuandHonoluluwheneverwindscomeoutofthesouthorsoutheast.

Pele

KīlaueaisconsideredtobethepresenthomeofPele,thevolcanogoddessofancientHawaiianlegend.Severalspeciallavaformationsarenamedafterher,includingPele'sTears(smalldropletsoflavathatcoolintheairandretaintheirteardropshapes)andPele'sHair(thin,brittlestrandsofvolcanicglassthatoftenformduringtheexplosionsthataccompanyal