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Urban Geology in London No. 36 ©Ruth Siddall; UCL, April 2017 1 A fire-spitting volcano in Deptford? Urban Geology in Southeast London Ruth Siddall No, there are no volcanoes in Deptford, and there have probably never been any throughout at least the last 1000 million years. The title of this urban geological walk comes from an observation of an astonished and bewildered resident of the Gleichburg in Germany who may (or may not) have witnessed a volcanic eruption there in the 18 th Century (see Grattan et al., 2000). In February 2017, SmashFest UK celebrated volcanoes and all things volcanic in their community science festival based in Deptford, south east London. Part of this event included a geological tour of the area’s (mainly) igneous rocks, used as paving, street furniture and building materials. This is a write up of that tour with the additions of a few other local buildings worthy of geological interest. The walk starts at the Albany Theatre on Douglas Way, SE8 4AG. From the main entrance of The Albany, turn left and then left again crossing the market place into Deptford Market Yard. Deptford Market Yard The redevelopment of Deptford’s Market Yard and the impressive Victorian Carriage Ramp was undertaken by Farrer Huxley Associates in 2015. The Ramp itself was designed and built from brick by Colonel George Thomas Landmann (1780-1854) of the Royal Engineers in 1835. The London & Greenwich Railway was London’s first railway line, opening in 1836 and passengers were carried on an elevated line, hence the requirement for an access ramp. The line ran from Greenwich to London Bridge, and Deptford was the first stop. The 2015 redevelopment has placed shops and cafés in the Ramp’s arches and has paved the Yard to make a very pleasant place for socialising on the way to and from the station. The Market Yard has been paved with a range of Chinese granites and related rocks which are very popular for city paving at present; mainly because they are available in large quantities and are relatively cheap, whilst being hard-wearing and attractive. Granites are igneous rocks; those that have crystallised from the solidification of a melt and

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Afire-spittingvolcanoinDeptford?UrbanGeologyinSoutheastLondon

RuthSiddall

No,therearenovolcanoesinDeptford,andtherehaveprobablyneverbeenanythroughoutatleastthelast1000millionyears.ThetitleofthisurbangeologicalwalkcomesfromanobservationofanastonishedandbewilderedresidentoftheGleichburginGermanywhomay(ormaynot)havewitnessedavolcaniceruptionthereinthe18thCentury(seeGrattanetal.,2000).InFebruary2017,SmashFestUKcelebratedvolcanoesandallthingsvolcanicintheircommunitysciencefestivalbasedinDeptford,southeastLondon.Partofthiseventincludedageologicaltourofthearea’s(mainly)igneousrocks,usedaspaving,streetfurnitureandbuildingmaterials.Thisisawriteupofthattourwiththeadditionsofafewotherlocalbuildingsworthyofgeologicalinterest.ThewalkstartsattheAlbanyTheatreonDouglasWay,SE84AG.FromthemainentranceofTheAlbany,turnleftandthenleftagaincrossingthemarketplaceintoDeptfordMarketYard.DeptfordMarketYardTheredevelopmentofDeptford’sMarketYardandtheimpressiveVictorianCarriageRampwasundertakenbyFarrerHuxleyAssociatesin2015.TheRampitselfwasdesignedandbuiltfrombrickbyColonelGeorgeThomasLandmann(1780-1854)oftheRoyalEngineersin1835.TheLondon&GreenwichRailwaywasLondon’sfirstrailwayline,openingin1836andpassengerswerecarriedonanelevatedline,hencetherequirementforanaccessramp.ThelineranfromGreenwichtoLondonBridge,andDeptfordwasthefirststop.The2015redevelopmenthasplacedshopsandcafésintheRamp’sarchesandhaspavedtheYardtomakeaverypleasantplaceforsocialisingonthewaytoandfromthestation.TheMarketYardhasbeenpavedwitharangeofChinesegranitesandrelatedrockswhichareverypopularforcitypavingatpresent;mainlybecausetheyareavailableinlargequantitiesandarerelativelycheap,whilstbeinghard-wearingandattractive.Granitesareigneousrocks;thosethathavecrystallisedfromthesolidificationofameltand

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canformcanforminmanyenvironmentswithintheEarth’scrust.Theyare‘Plutonic’rocksratherthan‘Volcanic’.NamedaftertheGreekgodoftheunderworld,Pluto,granitescrystallisefroma‘magma’underground,usuallyatdepthsof5ormorekilometres.Somegranitescanoccuratmuchshallowerdepthsandthesecanbethemagmachambersthatfeedvolcanoesandarethesourceof‘lava’whichisliquidontheEarth’ssurfacebeforeitfreezes.Asarocktype,a‘granite’isdescribedasbeingaplutonicigneousrockcomposedofthemineralsquartz,micaandfeldspar.Allgranitesbydefinitionhavethisbasicrecipe,butlikeice-creams,theycancomeinallkindsofdifferentflavours.Tracemineralsandelementscanalterthecolourofthemajormineralsandgrainsizeandshapecanvary.AlthoughastonemasonwouldcallallthestonesusedhereinDeptfordMarketYard‘granites’,geologicallywehaveherethreegranitesandarockcalledadiorite.Luckilytheyarealleasytodistinguishtoo,beingdifferentcolours.

LuoyuanGranite(topleft)haslargepinkandwhitefeldsparcrystalsaswellasquartzandablackvarietyofmica(biotite).ItisfromFujianProvinceinSEChina.Ithasanoverallpinkappearanceandisaverystrikingstone.ShandongRustGraniteisayellow-browngranitewhichgetsitsnamefromrustyspots,stripesandpatchesthroughoutthisrockswhichhavegivenanotherwisewhitegraniteayellowtorusty-browncolour.Therustisduetoironwhichhaspercolatedthroughthegraniteasithasbecomeweathered.LaizhouGranite(belowleft)isaratherunusuallookinggranite,withamedium-grained,greygroundmassmadeupofthethreemaingraniteminerals,quartz,micaandfeldspar.Howeveritisscatteredwithlargercrystals,2-3cmlong,ofwhiteandpink,well-shaped,feldsparcrystals.Someofthepinkcrystalshavewhiterims.Thecolourchangesrepresentsubtlechangesinchemistryasthemeltwascrystallising.Itiseasytomistaketheselargercrystalsforchewinggumonthepavement,butthenamefortheselargecrystalsinafinegrainedgroundmassisphenocrysts.ZhangpuGreenGraniteistheoddoneouthere,itisadiorite,anigneousrockcomposedoffeldspar,whichisusuallywhiteorgreyandadarkgreenmineralcalledhornblende,andthisiswhythisstoneasagrey-greencolour.Ithascrystallisedfromameltofadifferentchemistryfromthatofgranites.However,tostonecontractors,prettymuchalligneousrocksare‘granites’.

ZhangpuGreencomesfromFujianProvinceonthecoastofsouthernChina.Luoyuan,LaizhouandShandongGranitescomefromShandongProvinceonthecoastofsoutheastChina.AllwereintrudedduringtheMesozoicera,partofthegeologicaltimescalethatcomprisestheTriassic,JurassicandCretaceousPeriods,thetimeofthedinosaurs!ThiswasthetimethatthelandmassthatisnowsouthandeastChinawasbeingformedbyplatetectonicprocesses.TheSouthChinaSeawasbeingforcedundertheAsiancontinentalcrustbuildingmountainsalongthenewcoastlines.DuringtheMesozoic,thispartofSEAsiawouldhavebeenliketheAndeanMountainsofSouthAmericatoday–highmountainsandlotsofvolcanoes.Thegranitesanddioriteswehaveseenherewouldhavebeentheplumbing,feedingmagmatothevolcanoeswhereitcouldbeeruptedaslavasandvolcanicash.

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OnleavingDeptfordMarketYard,turnleftalongDeptfordHighStreet.AsmallpieceofevidenceofEnglishmagmatismcanbefoundonthecanbespottedonthekerb.FfinchStreetAVictoriankerbstonemadeofCornishGranitesurvivesamongsttheconcreteonthecornerofFfinchStreetandDeptfordHighStreet(below).TheCornishgranitesdidnotfeedvolcanoes,buttheydidproducespectacularrockswhichwerewidelyusedasbuildingstonesthroughoutthe19thCentury.

Thewhite,brick-shapedcrystalsarethemineralfeldspar,oneoftheessentialcomponentsofthegraniterecipe.Thecrystalshereshowsomealignment.Peopleoncebelievedthatthisalignmentwasduetothesolidcrystalsflowinginaliquidmelt.Howevermoltengraniteisextremelyviscous,somuchsothatwewouldnotthinkofitasaliquid.Ithasaconsistencymorelikepeanutbutter.Wenowbelievethatthesephenocrystsformedlaterinthecrystallisationhistoryofthegraniteandanyalignmentthatweseeisprobablymorelikelytoberelatedtodeformationoftherockratherthanflow.Ifyouwanttoseesomefossils,thentakeashortdiversiondowntoStPaul’sChurch.StPaul’sChurchStPaul’sisafineBaroquechurch,designedbyarchitectThomasArcherandcompletedin1730(seeCherry&Pevsner,2002).Ithasasemi-circularportico,supportedbycolumnsatthefrontentranceandporchesaccessedbystaircasesonthenorthandsouthsides.Geologicallywemustnowtakeadetourawayfromourigneousrocksandtheirassociationswithvolcanoes,forthechurchisbuiltfromLondon’smostfamousbuildingstone,PortlandStone.The17thcenturyarchitectInigoJoneswasinfluentialinbringingPortlandStonetoLondon.HeusedittobuildtheRoyalBanquetingHouseontheMallin1620.AftertheGreatFireofLondonin1666,useofPortlandStonetookoffanditwasusedbyChristopherWrentorebuildStPaul’sCathedral.FromthenonitbecameLondon’smainbuildingstoneanditwasoftenusedforcivicbuildingsandchurches.PortlandStoneisapale-greylimestoneoflatestJurassicage,deposited145millionyearsagoinwarm,shallow,tropicalseas,fulloflife.Evidenceofthiscanbeseeninthefossilshellsthatareeasilyspottedinthisstone.Giventhisbuildingisnearly300yearsold,thePortlandStonehasweathered,andtheharder

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fossilsnowstandproudofthesurface.Theseareoystershellsandthelaminatedstructureoftheirshellshasbeenwellpreserved.ThepresenceofthesefossilstellsusthatthisisthevarietyofPortlandStoneknownasWhitbed.

FossilsinthestonesofStPaul’sChurch.Topleftandright,PortlandWhitbedwithfossiloystershellfragmentsweatheringproudofthesurface.Bottomleftandright,varietiesofPurbeckStonewithvariousfossilisedfreshwatershellsandalgae.PurbeckStoneisEngland’s‘marble’.Itisnotatruemarbleinthegeologicalsensebutitisanarchitecturalmarbleinthesensethatitisalimestonethattakesagoodpolish.Itwasverypopularinecclesiasticaldecorations.IntheexteriorofStPauls,weseeitaspavingonthenorthandsouthsideporches,whichareaccessedbysymmetricalstaircases.Theseareasarepavedwithared,sandylimestonecalledMansfieldRed,fromNottinghamshire,PortlandStoneandthevarietiesofPurbeckstonewhichareillustratedabove.GeologicallythePurbeckBedsoverlythePortlandStone,markingnotonlyamajorchangefrommarinetofreshwaterenvironments,butalsothechangefromtheJurassictotheCretaceousera.Thefossilsindicatethischangeinenvironmentwithfreshwatersnailsandmusselstakingtheplaceoftheseashellfossilsfound

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inthePortlandStone.PurbeckStonehasalsorevealedrarefossilsofreptileboneandinsectsaswellasoccasionaldinosaurfootprints.PurbeckhasbeenquarriedsincetheRomanperiodfromquarriesaroundthevillageofLangtonMatraversontheIsleofPurbeckinDorset.Thebedsarethinandthereisalotofvariabilityintheappearanceofthevariousstonesand‘marbles’extractedfromthesestrata.LeavethechurchyardandturnleftbackontoDeptfordHighStreet.RetraceyoustepsbacktothestationandTomi’sKitchenoppositethestationendofDeptfordMarketYard.Tomi’sKitchenTomi’sKitchenRestaurantat126,DeptfordHighStreetusedtobeapub,TheMechanicsArms1,andithasverytypicalstoneworkforaLondonPub(seeSiddall,2014).Pubswereintendedtolooksmartandclassy,butnottooclassy!NofancymarblesinLondon’spubs.ThestoneofchoicewasacolourfulgraniteusuallyfromScotlandorScandinavia.HereatTomi’sKitchenwehavered,ScandinaviangranitesandinfactbothhereareoriginallyfromtheeastcoastofSweden.LiketheoneswehaveseenaboveintheMarketYard,theyhavethestandardquartz+feldspar+micarecipe.ThetwovarietiesareSwedishBalmoralGranite(belowleft)andGraversforsGranite(belowright).

Bothgranitescontainbrick-redfeldsparsandtheblackmica,biotite.ThewhitemineralinSwedishBalmoralGraniteisquartz,andthisgivesthegraniteared-and-whiteappearancethatcanbeseeninthephotographabove.GraversforsGraniteontherightismoreofapurplecolouroverall,andthisisdowntothequartzbeingalmostvioletincolour,partlyduetothefactithasbeencrushedandalsobecausethereisalotofironoxide(themineralhematite)inthistoo.Theseareextremelyancientrocks,almosttwobillionyearsold(1800millionyearsold).ThesearecertainlytheoldestthingsonDeptfordHighStreet!ContinuedowntheHighStreettoGiffinStreet.GiffinStreetHereintheplazaonGiffinStreet,wegettoseesolidifiedlavaflowsinDeptford.Thisstoneisusedforthecubeseatingblocksintheplaza.ThisisanotherChinesestonecalledBlackPearlBasalt.Abasaltisavolcanicigneousrock.Basaltsarecomposedofthedarkcolouredmineralsolivine,pyroxeneandavarietyoffeldsparandareconsequentlyblackincolour.Thesebasaltswereeruptedasenormouslavaflows,fiftymetresthick,duringtheCretaceous,around140millionyearsago.Theseeruptionswouldhavebeen

1 TheLostPubsProject:http://www.closedpubs.co.uk/london/se8_deptford_mechanicsarms.html

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unimaginablyhuge,nothinglikethemhasbeenseeninhumanhistory.ThegraniteswehaveseeninDeptfordMarketYardandtheirrelatives,wouldhavebeenthemagmasfeedingtheseenormousvolcanoeswhicharetruesupervolcanoes.Therecraterswouldhavebeen50milesacrossandmostoftheeruptiveproductswouldhavebeenvolcanicashandpyroclasticflows.Basaltswereonlyasmallproportionmaterialerupted.Howeverthesolidifiedflowsarestillenormous,formingcolumns(whicharetypicalofthickbasaltflows)whichcanbeseeninthequarriesinBailininFujianProvince.Thesecolumnsformasthelavacoolsandsolidifies,andareupto2-3metresdiameter(seebelow,right).Asaresult,largeblockswithnocrackswithinthemcanbeproduced.

Aboveleft;theporphyrybasaltatGiffinStreet.Right;TheBlackPearlquarriesinFujianProvince,China(photofromStoneContacthttp://www.stonecontact.com/quarries-2209/china-black-basalt-quarry).Lookingcloselyatthepolishedsurfacesoftheblocksandyoucanseethattheycontainblackspots.Thesearephenocrystsofthemineralpyroxene.Ifyoucanseeanygreencrystals,thesearethemineralolivine,sonamedbecauseitisolivegreen.Youcanalsoseethatthegroundmassisveryfine-grained.Thisvarietyoftextureinrocksiscalleda‘porphyry’.ContinuesouthalongDeptfordHighStreet.DeptfordHighStreetThegreenpavingcobblesaroundthejunctionwithGiffinStreetandDouglasWayareZhangpuGreenGranite.ThepatternofdifferentcolouredgranitesseeninDeptfordMarketYardisonceagainusedontheHighStreet;pinkisLuoyuanGranite,greyisLaizhouGraniteandthebrownisShandongRustGranite.

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ThelaststoponDeptfordHighStreetonthecornerofNewCrossRoadistheBroadwayRestaurant,ariotofgranites.BroadwayRestaurantOnthecornerofDeptfordHighStreetandDeptfordBroadway,TheBroadwayRestaurantalsohadaformerlifeasapub,TheCenturion2.Itisalsocladinavarietyofgranites,threeScottishandoneFinnish.PeterheadGraniteisthepalepinkgraniteusedformostofthesquaresectionpillarsbetweenthewindows.AsthenamesuggestitisfromPeterhead,afishingtownnorthofAberdeenontheeastcoastofScotland.IthassalmonpinkfeldsparsandsmokygreyquartzandlooksabitlikecoarseArdennespaté.Althoughnolongerquarriedtoday,thisstonewasverymuchinfashionduringtheVictorianandEdwardianperiodsandisusedtocladagreatmanypubsandusedasplinthsforstatuesetc.Itwasintrudedjustover400millionyearsagoduringtheformationofScotland’smountains.ThegreygranitepanelsbetweenthewindowsareCairngallGranitewhichalsocomesfromPeterhead,andthiswasquarriedclosetothepinkgranitequarriesatFlushing.Thequarriesarelongsinceclosedandarenowariflerange.CairngallGraniteismucholderthanPeterhead,at475millionyears.Justnextdoortothemainrestaurantat14,DeptfordHighStreetthebuildingschemecontinues.Atsometimeintherecenthistoryofthebuilding,therehasbeenneedtoreplacesomeofthePeterheadGranite,presumablybecauseitwasdamaged.Asitisnolongerworked,ithasbeenreplacedusingBalmoralGranitefromFinland.Thisgranitehascrystalsformingamosaicofbrick-redfeldsparsanddark-grey,almostblack,quartzisone-and-a-halfbillionyearsold.Itcomesfromthesouth-westcoastofFinland.

ThesmallpillarsoneachsideofthedooraremadefromDalbeattieGranitefromsouth-westScotlandalsoaround400millionyearsold.Thishaswhiteapalepinkfeldspars,blackbiotitemicaandgreyquartz.Thepillarnthelefthandsidehasadark-grey,raggedpatchinit.Thisisafeaturethatgeologistscalla‘xenolith’whichliterallymeansa‘strangerock’.Itisnotpartofthegranite,butpartofthepre-existingcountryrocksthatthemeltwasintrudedinto.Thereforeitisarockthatisolderthanthegranitethathasnotbeenincorporatedintoitandnotdissolvedintothegranitemagma(left).

ThisistheendofthemaintouroftheurbangeologyoftheareaaroundDeptfordHighStreet.HoweverifyouareheadingtowardsNewCross,thereareafewbuildingsworthyofgeologicalnotealongNewCrossRoad.InLondon’ssuburbs,mostbuildingisinbrick,butpubsandcivicbuildingsaregoodplacestospotsomegeology.TheNewCrossInnandNewCrossHouseareoppositeeachother,atthejunctiononNewCrossRoadandLewishamWay.NewCrossInnAnotherearly20thCenturypub,theNewCrossInnhasitsgroundfloorcladwithaScandinavianigneousrock.ThistimeitisfromthetownofLarvikinsouthernNorwayanditisnamedlarvikite.Larvikiteisnotagranitebecauseitdoesnotcontainanyquartz.Itisavarietyofrockcalledamonzonite.ItwasintrudeintotheOsloriftvalley(nowtheOsloFjord)around290MaduringthePermian.Larvikitehasbeenquarriedinacommercialscalesincethe1880sandasbecomeverypopularworldwideasastrong,hard-wearingandveryattractivestone.Itisfamousforitsiridescentfeldsparswhichshimmerandchangecolourasyou 2TheLostPubsProject:http://www.closedpubs.co.uk/london/se8_deptford_centurion.html

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moveyourhead;sometimesappearinggreyandsometimeselectricblue.Anumberofvarietiesofthisstonerangingincolourfromalmostblack,throughbluetogreyarequarried.ThisisthegreyvarietywhichgoesbythenameMarinaPearlLarvikite.Theimagebelowshowsthegrey,iridescentfeldspars.Theblackmineralsarebiotitemica(whichwehaveseeninsomeofthegranites)andpyroxene(whichwesawinthebasaltinGiffinPlace).

LarvikiteontheNewCrossInn.

WeknowthatthelarvikitemagmaschambersoftheOsloriftweredefinitelyfeedingvolcanoes.Weseetheproductsofthesevolcanoeswhichstillsurviveassolidifiedlavaflows,withverydistinctivediamond-shapedorrhombicfeldspars.Theserocksareknownasthe‘rhombporphyries’andtheyareavarietyoflavaswhichgeologistscalllatites.TheyareuniquetothePermianmagmatismoftheOslorift.Duringtheiceages,thesevolcanicandplutonicrockswereheavilyeroded(andthisprocesshelpedtoexposethelarvikiteintrusions).Chunksofrhombporphyrywerecarriedsouthbyglaciersandicesheetsanddumpedinmorainesandglacialsedimentswhentheicesheetsmelted.TheycannowbeenfoundintheglacialgravelsofSEEngland,andbecauseoftheiruniqueness,weknowexactlywheretheycamefrom.Thishasgivenuslotsofinformationabouthowfar,howfastandinwhatdirectiontheicesheetsmoved.

ApolishedslabofrhombporphyryfrozenlavaintheNationalMuseumofScotland.Thelargestcrystalsare1cmlong.PhotobyRuthSiddall.

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TheNewCrossHouseAcrosstheroadfromtheNewCrossInnistheNewCrossHouse.ThisiscladinBritishgranites;MerrivaleGranitefromDartmoorandCairngallGranitefromPeterheadinAberdeenshire,Scotland.WehaveseenCairngallearlieronTheBroadwayRestaurant.MerrivalecomesfromtheotherendoftheBritishIslesandisoneofthesuiteofgranitesintrudedintoDevonandCornwallaround300millionyearsago.Ithaslargewhitefeldsparphenocrystsandslightlybrownishquartz.Cornishgranitestypicallyhavetwotypesofmica;theblackbiotiteandasilveryvarietycalledmuscovite.Thiscanbeseensparklingintherock,especiallyifthesunisshining.MerrivaleGranitewasquarriedbytheprisonersincarceratedinDartmoorPrison.

StonesontheNewCrossHouse.Left;CairngallGraniteandright;MerrivaleGranite.

DeptfordTownHallLikeStPaul’sChurch,theoldDeptfordTownHallbuildingisconstructedofPortlandStone.TheintricatecarvingabovethemaindoorisenabledbyPortland’spropertiesasafreestone,thatis,astonewhichhasnopreferredweaknessandthereforecanbecarvedinanydirection.Asaconsequence,elaborateandintricatecarvings,asobservedinthisfishycoatofarms,representingDeptford’smaritimeassociations(below).ThebuildingwasdesignedbyarchitecturefirmLanchesterStewartPickardsandbuiltin1905.

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References

Cherry,B.&Pevsner,N.,2002,TheBuildingsofEngland:LondonNo.2,South.,YaleUniversityPress,Newhaven&London.,808pp.

Grattan,J.P.,Gilbertson,D.D.&Dill,A.,2000,AfirespittingvolcanoinourdearGermany?DocumentaryevidenceforalowintensityvolcaniceruptionoftheGleichbergin1783,in:McGuireW.G.,Griffiths,D.R.,Hancock,P.L.&Stewart,I.S.(Eds.)TheArchaeologyofGeologicalCatastrophes,SpecialPublications,GeologicalSocietyofLondon,171,307-315.

Siddall,R,2014,London’spubgeology:aspotter’sguide.,UrbanGeologyinLondonNo.20,18pp.,http://www.ucl.ac.uk/~ucfbrxs/Homepage/walks/PubGeology.pdf

Glossary

Basalt–avolcanicrockcomposedofthemineralsfeldspar,pyroxeneandolivine.

Diorite–aplutonicigneousrockcomposedfromthemineralsfeldsparandhornblende.

Freestone–arockwithnoplanesofweakness,meaningitisverygoodforthree-dimensionalcarving.

Granite–aplutonicigneousrockthatiscomposedoftherockformingmineralsquartz,feldsparandmica.

Igneous–atypeofrockthathasformedbythecrystallisation(freezing)ofasilicatemelt.

Lava–asilicatemeltontheEarth’ssurface,eruptedfromavolcano.

Magma–asilicatemeltwithintheEarth.

Mineral–asolidmaterialwithadefinedchemicalformula.

Phenocryst–alargecrystalinafinergrainedgroundmassinanigneousrock.

Plutonic–referringtoanigneousrockwhichhasformedwithintheEarth’scrust.

Porphyry–anigneousrockwithphenocrysts,whichthereforehasaspeckledappearance.

Pyroclasticflow–atorrentofrockfragmentsandashproducedbyaveryexplosivevolcaniceruption.

Rock–asolidmaterialmadeupofminerals.

Stonecontractor–thebusinessthatliaiseswithaquarrytosupplystoneattherequestofarchitects.

Volcanic–referringtoanigneousrockwhichhasbeeneruptedontotheEarth’ssurface.

IndexofStones

BalmoralGranite–BroadwayRestaurant(right)

BlackPearlBasalt–Giffinstreetsquare

CairngallGranite–BroadwayRestaurant,TheNewCrossHouse

CornishGranite–FfinchStreet

DalbeattieGranite–BroadwayRestaurant

GraversforsGranite–Tomi’sKitchen

LaizhouGranite–DeptfordMarketYard,HighStreet.

LincolnshireLimestone–StPaul’sHouse

LuoyuanGranite–DeptfordMarketYard,HighStreet.

MansfieldRed–StPaul’sChurch

MarinaPearlLarvikite–NewCrossInn

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MerrivaleGranite–TheNewCrossHouse

PeterheadGranite–BroadwayRestaurant

PortlandStone–StPaul’sChurch,DeptfordTownHall

PurbeckStone–StPaul’sChurch

ShandongRustGranite–DeptfordMarketYard,HighStreet.

SwedishBalmoralGranite–Tomi’sKitchen

ZhangpuGreenGranite–DeptfordMarketYard,HighStreet.

DeptfordMarketYardandCarriageRamp.

Howtocitethisarticle:Siddall,R,2017,Afire-spittingvolcanoinDeptford?UrbanGeologyinSoutheastLondon.,UrbanGeologyinLondonNo.36,11pp.,http://www.ucl.ac.uk/~ucfbrxs/Homepage/walks/Deptford.pdf

LocationsofthebuildingsdescribedaboveandbriefdetailsofthestonesusedcanalsobefoundintheLondonPavementGeologywebsite:http://londonpavementgeology.co.uk©DrRuthSiddall,UniversityCollegeLondon,GowerStreet,LondonWC1E6BT,UK:[email protected]

Downloadsfromhttp://www.ucl.ac.uk/~ucfbrxs/Homepage/UrbanGeology.htm;Facebook|Cultural&UrbanGeology|Twitter:@R_Siddall|#UrbanGeology