TheLangholmandNewcastletonHillslieonthesouthernmarginoftheSouthernUplandsTerrane,arockymassif,whichhasbeenanareaofgenerallypositivereliefforatleast420millionyears(Ma).

The‘basement’rocksoftheterranearethegreywackesandstonesandsiltstonesoftheRiccartonGroupseenatPeden’sViewandMonumentViewquarries(localities1and2).Thesearedepositsinwhichtheoriginalsandandmudsedimentwastransportedbyhigh-energyturbulentsediment/waterslurries(turbiditycurrents)fromcontinentalshelfareas,viasubmarinecanyons,ontolargedeep-watersubmarinefansintheIapetusOcean.Evidenceforthisorigincanbeseenonbeddingplanes,manyofwhichshowexamplesofcharacteristicsedimentarystructuresknownasflute-,groove–orprod-casts.Theseareacommonfeatureofsuchturbiditedepositsandwereformedwheneitherspinningvorticesor‘tools’(rockfragmentscarriedalonginthecurrent)erodedorcutdownintotheunderlyingmudontheseafloor.Differentialloadingatthesoftsand/mudinterfacetendedtoemphasisethedepthprofilesofthesemarks.

TheIapetusOceanlaybetweenScotlandandEnglandduringOrdovicianandSiluriantimes,some470-420Ma

agoandclosedduetothemovementofhugecrustalplates.Thegreywackesandstoneslaiddownintheoceanweresqueezedupandintenselyfoldedtogivethesteeplydippingbedsweseetoday.

WELCOME TO THE LANGHOLM AND NEWCASTLETON HILLSThe rocks and landscape of the Langholm andNewcastleton Hills can be used to demonstrate manyaspects of the geological history of southern Scotlandduring the last430millionyears. Over thisperiod, thebasementofolderrocks,laiddowninanoceanseparatingScotland and England, were thrust up into a mountainchain. This was then eroded down and the sedimentdeposited in deserts, river valleys, deltas and shallowseas.

DuringearlyCarboniferoustimes,volcanicactivityledtotheoutpouringoftheBirrenswarkLavasinthearea.Themostrecentgeologicalevent,theDevensianglaciation,anditssubsequentretreat,hashadaprofoundinfluenceinerodingandsmoothingtheunderlyingrockanddepositingboulderclay,sandandgravelinthevalleys.

By visiting the localities described overleaf, you canexploreandstudythelandformsandthenaturalandman-madeexposuresintheareatounderstandthegeologyanddiscoverhowitinfluencesthelandscapeallaroundus.

The importance of this geology, landscape and naturalheritage is formally recognised in thedesignationof theLangholm and Newcastleton Hills as a Site of SpecialScientificInterest(SSSI)andSpecialProtectionArea(SPA).

Findfurtherinformationaboutmanyotherattractionsinthesurroundingareaatwww.langholm-online.co.ukorbycontactingtheLangholmInitiativeatAshleyBankHouse,Langholm,DG130DJ.Tel:(013873)80914.Email:enquiries@langholminitiative.co.uk

Please respect the country code,wear appropriate clothing andfootwear and park in designatedareas.Enjoyyourvisit!

TheMoorlandProjectisapartnershipbetweenTheLangholmInitiativeandTheBuccleuchEstatesLtd.

Thegeneroussupportofall involvedwith theMoorlandProjectisgratefullyacknowledged.ProjectManagerEmma-JaneAhart.

TextbyDr.JamesD.Floyd.Photographs by Dr. James D. Floyd, Andrew McMillan

andcourtesyoftheBritishGeologicalSurvey.ArtworkanddesignbyJohnHills.

GEOLOGY OF

THE LANGHOLM & NEWCASTLETON

HILLS

A SPECIAL PLACE

Above:PermianredsandstonesformingcliffonsouthbankoftheRiverEskatCanonbie.Theserockswerelaiddowninadesertandshowtracesofdune-bedding.

Left:ModernalluviumnexttotheRiverEskatCanonbie.Atleastthreehigherterracescanbeseeninthebackground,eachrepresentingolderandhigherriverlevelssincethePleistoceneglaciation.

Above:Smallflutecastsonbaseofagreywackebed,Peden’sViewQuarry.

Right:CrosssectionthroughaSiphonodendroncolonyinCarboniferouslimestoneatPentonLinns.Thesewerecolonialcoralswhichhelpedtobuildlargereefsinshallowtropicalseas.Thewhiteringstotherightofthecoinaredisarticulatedcrinoid(SeaLily)columnals.

AfterclosureofIapetus,theSouthernUplandsformedamountainrange,whichwasgraduallyerodedoverthenext70Ma.

ByearlyCarboniferoustimes(c.350Ma),thereliefwasalmostsimilartotodaythoughtheconditionswerehotandinitiallyarid.However,ashallowmarinebasin,knownastheNorthumberlandTrough,layroughlyalongtheSolway.Volcanicactivityatthattimeledtotheoutpouringofbasalticlavas,examplesofwhichcanbeseenatSkipper’sBridge(locality4).

Overtime,thelavaswerecoveredbythickriversandstones(suchastheWhitaSandstoneatlocality3)andlagoonallimestonesandmudstones,whichwerelaiddownastheclimategraduallybecamemoremoistandtropical.

AstheNorthumberlandTroughgraduallysubsided,theseaextendedfarthernorthwardsandtheshallowmarinelimestones,sandstonesandmudstonesofthePentonLinnssection(locality6)weredeposited.ThesehavemarinebrachiopodfossilsandbothsolitaryandcolonialcoralssuchasSiphonodendron.Asthebasinfilledandconditionsbecamemoredeltaic,sandstonesuchasatGilnockieBridge(locality5)andcoalsweredeposited.

ByPermiantimes(c.290Ma),desert-likeconditionshadreturnedandtheredsandstonesofCanonbiewerelaiddown(locality7).

AfterthePermian,thereisalmostnogeologicalrecordpreservedintheareauntiltheevidenceofglaciationduringthePleistoceneIceAgesoftheQuaternary.Whentheglaciersfinallyretreatedabout13,000yearsago,rapidly-releasedmeltwaterlaiddownhugespreadsofalluvium,which,sincethen,havebeengraduallyerodedintoterrace’staircases’suchasthoseseenintheRiverEskatCanonbie.

Large pothole c. 1m across, cut insandstone,LiddelWater,PentonLinns.The boulder trapped inside mustweigh several hundred kilogramsbuthasbeentransportedbytheriver.

Geologists’AssociationCurryFund

Explore the geology of

THE LANGHOLM & NEWCASTLETON HILLS

A SPECIAL PLACE

2MonumentViewQuarry(NY374851)QuarrybesideminorroadtoMacDiarmidMemorial.Below: Thin-bedded greywacke sandstonesdip south but are overturned. A small faultcutsthefacefrombottomlefttotopright.

Left:Thesetoolmarkson the underside ofbeds were producedby small rockfragments carried inthe turbidity current.They sometimesprovide, as in thisexample, evidenceof different currentdirections.

7Canonbie(NY395765)Walk downstream from road bridge(B6357)invillage.Above: River alluvium lying onCarboniferoussiltstone.Below: Beds of Permian conglomeratedippingdownstreaminRiverEsk.

3WhitaHill(NY379847)Walk from car park at MacDiarmidMemorial.Above:TheMalcolmMonument on top ofthehillisbuiltoflocalWhitaSandstone.Below:View toeast fromWhitaHill. Thedark foreground isWhita Sandstone, withthe more distant ground underlain byyounger sandstones of the Border Group.The prominent hill in the centre distanceisTinnisHill, an agglomerate-filledventofLowerCarboniferousage.

1Peden’sViewQuarry(NY344862)Roadsideexposure(B709).Below:Thin- and medium-bedded greywackesandstones, which dip southwards but areoverturned.Right: The original ‘way-up’ of beds can bedetermined usingsmall-scalesedimentarystructuressuchastheseflute casts, whichcan be seen on theundersides of many ofthe sandstone beds inthequarry.

5GilnockieBridge(NY385781)Roadsideexposuresbelowbridge(oldA7).Above: Gently-dipping limestones in thebedoftheRiverEsk.Below:LargefallenblocksofcoarseCoalMeasuressandstoneonthenorthbank.Thebridge’s central pillar is founded on thissandstone.

6PentonLinns(NY432774)Walkdownstreamonnorthbankalongroughnarrowtrackfrombridge.Above left: Eroded blocky joints in limestone pavement, Liddel Water. This isreminiscentofkarstweatheringinuplandareas.Aboveright:Coreofanticlineinfoldedlimestonebeds.

4Skipper’sBridge(NY372833)Path to river below bridge from roadside(A7-B6318).Above:Thebridgeisbuiltonbasaltlavas.Below:Thesesmallholesinthelavawereoriginally gas bubbles. They are calledamygdaleswhenlaterinfilledwithcalcite.