The Gediz River fluvial archive: A benchmark for Quaternary research in Western Anatolia

18 Pages·2017·5.84 MB·English

by  D. Maddy

QuaternaryScienceReviews166(2017)289e306
ContentslistsavailableatScienceDirect
Quaternary Science Reviews
journal homepage: www.elsevier.com/locate/quascirev
The Gediz River fluvial archive: A benchmark for Quaternary research
in Western Anatolia
D. Maddya,*, A. Veldkampb, T. Demirc, W. van Gorp d, J.R. Wijbrans e,
D.J.J. van Hinsbergen f, M.J. Dekkers f, D. Schreve g, J.M. Schoorl h, R. Scaife i,
C. Stemerdink a, T. van der Schriek a, D.R. Bridgland j, A.S. Aytaç k
aSchoolofGeography,PoliticsandSociology,NewcastleUniversity,NewcastleuponTyneNE17RU,UK
bFacultyofGeo-InformationScienceandEarthObservation(ITC),TwenteUniversity,Enschede,TheNetherlands
cAkdenizÜniversitesi,EdebiyatFakültesi,Cog(cid:1)rafyaBo€lümü,Konyaaltı,Antalya,Turkey
dGroningenInstituteofArchaeology(GIA),UniversityofGroningen,Poststraat6,9712ERGroningen,TheNetherlands
eDepartmentofEarthScience,VUUniversity,DeBoelelaan1085,1081HVAmsterdam,TheNetherlands
fDepartmentofEarthSciences,UtrechtUniversity,Heidelberglaan2,3584CSUtrecht,TheNetherlands
gDepartmentofGeography,RoyalHollowayUniversityofLondon,EghamTW200EX,UK
hSoilGeographyandLandscapeGroup,WageningenUniversity,P.O.Box47,6700AAWageningen,TheNetherlands
iSchoolofGeographyandEnvironment,UniversityofSouthampton,SouthamptonSO171BJ,UK
jDepartmentofGeography,DurhamUniversity,SouthRoad,DurhamDH13LE,UK
kDepartmentofGeography,HarranUniversity,63300,Sanliurfa,Turkey
a r t i c l e i n f o a b s t r a c t
Articlehistory: The Gediz River, one of the principal rivers of Western Anatolia, has an extensive Pleistocene fluvial
Received28February2016 archivethatpotentiallyoffersauniquewindowintofluvialsystembehaviouronthewesternmarginsof
Receivedinrevisedform AsiaduringtheQuaternary.InthispaperwereviewourworkontheQuaternaryGedizRiverProject
7July2016 (2001e2010)andpresentnewdatawhichleadstoarevisedstratigraphicalmodelfortheEarlyPleis-
Accepted24July2016 tocenedevelopmentofthisfluvialsystem.
Availableonline6October2016
InpreviousworkweconfirmedthepreservationofelevenburiedEarlyPleistocenefluvialterracesofthe
GedizRiver(designatedGT11,theoldestandhighest,toGT1,theyoungestandlowest)whichliebeneaththe
Keywords:
basalt-coveredplateauxoftheKulaVolcanicProvince.Decipheringtheinformationlockedinthisfluvial
GedizRiver
Pleistocene archiverequirestheconstructionofarobustgeochronology.Fortunately,theGedizarchiveprovidesample
Fluvialarchive opportunityforage-constraintbaseduponageestimatesderivedfrombasalticlavaflowsthatrepeatedly
Buriedriverterraces enteredthepalaeo-Gedizvalleyfloors.Inthispaperwepresent,forthefirsttime,ourcompletedatasetof
40Ar/39Arageestimatesandassociatedpalaeomagneticmeasurements.Thesedata,whichcanbedirectly
relatedtotheunderlyingfluvialdeposits,provideageconstraintscriticaltoourunderstandingofthissequence.
ThenewchronologyestablishestheonsetofQuaternaryvolcanismat~1320ka(MIS42).Thisvolca-
nism,whichisassociatedwithGT6,confirmsapre-MIS42ageforterracesGT11-GT7.Evidencefromthe
colluvial sequences directly overlying these early terraces suggests that they formed in response to
hydrologicalandsedimentbudgetchangesforcedbyclimate-drivenvegetationchange.Thecyclicfor-
mationofterracesandtheirtimingsuggeststheyrepresenttheobliquity-drivenclimatechangesofthe
EarlyPleistocene.BywayofcontrasttheGT5-GT1terracesequence,constrainedbyalavaflowwithan
ageestimate of ~1247ka, span the time-intervalMIS42 e MIS38 and thereforedo notmatch the fre-
quencyofclimatechangeaspreviouslysuggested.Theonsetofvolcanismbreaksthesimplelinkageof
terracing to climate-driven change. These younger terraces more likely reflect a localized terracing
processtriggeredbybaselevelchangesforcedbyvolcaniceruptionsandassociatedreactivationofpre-
existingfaults,lavadamconstruction,landslidingandsubsequentlava-dammedlakedrainage.
EstablishingafirmstratigraphyandgeochronologyfortheEarlyPleistocenearchiveprovidesasecure
frameworkforfutureexploitationofthispartofthearchiveandsetsthestandardaswebeginourwork
ontheMiddle-LatePleistocenesequence.Webelievethisworkformsabenchmarkstudyfordetailed
QuaternaryresearchinTurkey.
©2016ElsevierLtd.Allrightsreserved.
* Correspondingauthor.
E-mailaddress:[email protected](D.Maddy).
http://dx.doi.org/10.1016/j.quascirev.2016.07.031
0277-3791/©2016ElsevierLtd.Allrightsreserved.
290 D.Maddyetal./QuaternaryScienceReviews166(2017)289e306
1. Introduction Demirci Basins before entering the morerecent, east-westorien-
tated,Plio-PleistoceneAlas¸ehir(Gediz)Graben.Ourprincipalarea
Overthepast150years,fluvialarchiveshaveprovidedcritical of interest, within the Kula Volcanic Province, is situated in the
stratigraphical information key to the unravelling of continental southernhalfoftheNeogeneSelendiBasin(Figs.2and3),where
stratigraphy,especiallyinWesternEurope.Thehighlydetailedbut theevolutionoftheGedizriversystemreflectsprogressiveincision
still incomplete database of Quaternary stratigraphical evidence intothickMioceneBasinfillsediments.Understandingthelithos-
generatedincountrieswithlongtraditionsofgeologicalmapping tratigraphyoftheBasinfillanditsprincipalstructuresistherefore
hasrecentlyledtoashiftawayfromthefundamentalquestionsof an essential context for understanding the Quaternary river
stratigraphytowardsamorefocussedthematicapproachtargeted behaviourandtheresultingfluvialarchive.
at,forexample,hazardmanagementandwealthcreation.However, ThelithostratigraphyoftheSelendiBasinfillwasfirstdescribed
forlargepartsoftheglobe,wheregeologicalinvestigationisoften in detail by Ercan et al. (1983) but was subsequently revised by,
initsinfancy,thereisstillmuchbasicmappingtobeundertaken amongstothers,Seyitog(cid:1)lu(1997),PurvisandRobertson(2004)and
before a comparatively firm local-regional stratigraphy can be most recently by Ersoyet al. (2010). Table 1 shows the Cenozoic
established. stratigraphybaseduponErsoyetal.(2010),withtheadditionofthe
At the outset, FLAG was initiated to promote work on fluvial GedizValleyFormation(seeMaddyetal.,2012a).
archivesworldwidebyenhancingdialoguebetweenworkersfrom The largely unconsolidated nature of much of the Basin fill
all continents. Fluvial archives from Europe and North America provides a readily erodible, but spatially variable, substrate for
werewell-represented,albeitstillwithgaps,intheliterature,but vertical and lateral fluvial erosion/deposition and accompanying
little detailed work was available from elsewhere. It was clear, slope processes. The nature of this substrate thus varies through
however, that some work had been undertaken in these areas of time as progressive fluvial incision proceeds, constraining valley
perceiveddatavacuumbutconsiderableadditionaleffortwouldbe geometry and therefore preservation potential, as lithological
neededtomakethisworkavailabletoawideraudience.Afurther properties either promote or dampen opportunities for valley
goalofFLAGwastobeginharmonisingthecollectionandreporting widening.ProgressiveincisionintotheBasinstratigraphyalsoleads
of observations, thus facilitating more effective regional tochanginghydrology,especiallywhereincisionremovescapping
comparisons. limestones and karstic drainage systems are abandoned. Faulting
Onesuchcollaborativeresearchprogrammetoemergefromthe structurescontributetothespatialandtemporalvariabilityinthe
early meetings of FLAG was an attempt to move just beyond the lithologyofthesubstrate,inadditiontoprovidingareasofweak-
boundaries of Europe into western Asia by looking at the fluvial ness,readilyexploitedbythefluvialsystemandhelpingtoposition
archives of Anatolia (Turkey). Specifically, as a result of a chance channelcourses.Thefaultsalsoactasconduitsforwaterandare
meeting with Dr Rob Westaway and his Turkish collaborator, Dr often associated with hot water springs and the deposition of
Sema Yurtmen, we were introduced to exposures of fluvial sedi- travertine. Finally, with the exhumation of the more resistant
mentsattributedtodepositionbyanancestralGedizRiverandits basement strata, the pre-Basin fill topography exerts increasing
tributariesintheregionoftheKulaVolcanicProvince.TheGediz control over drainage directions as stripping of the overlying
River,at~275kminlength,isoneoftheprincipalriversofWestern sedimentproceeds.
Turkey (Fig.1) and thus a prime target of interest. Although this Theoldestbasementrocks(Figs.2and3)underlyingthebasin
areahasbeenmappedbytheMTA(MineralResearch&Exploration fill are the pre-Neogene metamorphics of the Menderes Massif
General Directorate, Ercan et al.,1983), these fluvial deposits are (predominantlygneiss, schist, quartzite and marble). These rocks
largelyburiedbeneathbasalticlavaflowsandthussurfacemapsdo outcroponlyinthesouth-easternquadrantofourstudyarea(Fig.3)
notdisplaytheirgeometryorextent.Indeed,theextensivesurface andtheystructurallyunderlieCretaceousophiolitesandophiolitic
exposuresofdissectedMiocenesedimentsdominatethemapswith me(cid:3)langerocksthatoutcropmoreextensivelywithinourstudyarea
very limited surface outcrop of superficial unconsolidated sedi- especially north of I_brahimag(cid:1)a where ophiolitic hills reach over
ments of presumed Quaternary age often attributed to a poorly 550 ma.m.s.l. (Fig. 3). Althoughtheseoutcrops wouldhavebeen
definedAsartepeFormation(Figs.2and3).Giventheextensiveand buriedbeneathBasin fillformuchof theearliestQuaternary,the
oftenspectacularexposureoftheMioceneBasinfill,itisnotsur- exhumationofthehilltops,whichliewithinthealtitudinalrangeof
prisingthatthethinnerandburiedGedizRiverfluvialarchivehad theEarlyPleistoceneGedizvalleyfloor(seebelow)ismostlikelyto
beenlargelyoverlooked.Earlyresultsfromourinvestigationswere have occurred around ~1.5Ma. The significance of this change is
discussedduringanexcursiontothefieldareaassociatedwiththe discussedbelow.
FLAG2006meetingbasedinI_zmir. Theearliestdepositsin-fillingtheBasinaretheconglomerates
The Gediz River Project (2001e2010) results reported here and sandstones of the Hacıbekir Group (Kürtko}yü and Yeniko}y
present our latest stratigraphical model for the Early Pleistocene Formations),whichisgenerallyacceptedasEarlyMiocenein age
developmentofthisfluvialsystem.Thisoutcomebuildsuponour (Seyitog(cid:1)lu,1997; Westaway et al., 2003, 2004). This Group has a
previously reported work but, with the benefit of many newage restricted outcrop within the study area and comprises coarse
estimatesderivedfromassociatedlavaflowsandnewobservations, gradeandangulargravelsinterpretedasalluvialfanfaciesderived
addssignificantlytoourunderstanding,withimplicationsnotonly fromthetopographichighsofthemetamorphicandophiolitichills
for stratigraphy but also for establishing fluvial-system drivers, of the Early Miocene. These deposits, are extensively deformed,
environmental reconstruction and early hominin dispersal. We indicating an early Miocene phase of deformation (Purvis and
believe this work forms a benchmark study, signposting a way Robertson,2004).Thecurrentoutcropsliewellbeneaththelevels
forwardfordetailedQuaternaryresearchinTurkey. oftheEarlyPleistoceneGedizriverdepositsandthusitisunlikely
that these sediments were available to the river at that time. It
2. Pre-Quaternarystratigraphyandneotectonicsinthe remainspossible,however,thatsedimentsoftheHacıbekirGroup
SelendiBasin mayhavebeenremovedfromthehigherlevelsofthepre-Basinfill
topography.
OnitsroutetotheAegeanSea,theGedizRivertraversessomeof The I_nay Group unconformably overlies the Hacıbekir Group.
_
themostimportanttectonicstructuresofwesternAnatolia(Fig.2) Thestratigraphicsequenceof theInayGroup records progressive
including the NNE-SSWaligned Neogene Us¸ak-Güre, Selendi and in-fill of the Selendi Basin. Gently inclined to sub-horizontally
D.Maddyetal./QuaternaryScienceReviews166(2017)289e306 291
Fig.1. GenerallocationofthestudyareainWesternAnatolia,Turkey.InsetshowslocationofTurkeywithintheMediterraneanBasin.TPisTenaghiPhilippon.Alsoshownislocation
ofODP967(Kroonetal.,1998).DashedboxshowsapproximatelocationofFig.2.BackgroundimageistheASTERGlobalDigitalElevationModel(GDEM;ASTERGDEMisaproductof
METIandNASA)withheightsrangingfrom0to2400m.GridisinUTMZone35coordinates.
beddedsandsandsiltsupto~200minthickness,(AhmetlerFor- Formation, comprising reddish conglomerates and minor sand-
mation, Balçıklıdere Member) are overlain by fine-grained sand- stone,withlocallylaminatedlimestonelenses(ErsoyandHelvacı,
stonesandsiltsuptoafewtensofmetresinthickness(Ahmetler 2007;Ersoyetal.,2010).Thisformationiscappedontheeastern
Formation, Gedikler Member). 40Ar/39Ar age estimates of marginoftheSelendiBasinbytheKabaklarbasalt(Fig.2),which
18.89±0.58Mato16.42±0.09Mafromintercalatedtuffwithinthe has 40Ar/39Ar age estimates of 8.37 ± 0.07 Ma (Innocenti et al.,
Gedikler Member in the Selendi Basin suggest an Early to early 2005), confirming a minimum Late Miocene agefor the underly-
MiddleMioceneagefortheseunits(PurvisandRobertson,2005). ing Kocakuz Formation and by inference providing an upper age
_ _
TheInayGroupsequenceiscappedbyupto~300mofcarbona- limitfortheunderlyingInayGroup.Thesedimentsascribedtothe
ceous muds and silts, lacustrine facies of the Ulubey Formation, Kocakuz Formation by Ersoy et al. (2010) had previously been
whichrepresenttheendstageofBasinfill.TheageoftheUlubey mappedasQuaternaryAsartepeFormationbyErcanetal.(1983).
Formation in the Selendi Basin can be no younger than the Late This reassignment of former Asartepe Formation sediments may
_
Miocene (see below). The sediments of the Inay Group are the haveimplicationsforthestudyareawheresedimentsmappedas
predominantsourceofclasticsedimentspreservedwiththeGediz AsartepeFormationcropouteastandsouthofI_brahimag(cid:1)a(Fig.3).
ValleyFormation. TheKocakuzFormationandtheKabaklarbasaltareconsideredby
TheBasinfillsedimentsaresubsequentlydeformedduringthe Ersoy et al. (2010) to be genetically linked to a NW-SE-trending
Late Miocene as a result of tectonic extension evidenced by the dextral oblique to strike slip fault, suggesting a phase of strike-
formation of large numbers of NNE-SSW trending normal faults slip deformation following the earlier extensional faulting but
(Yilmaz et al., 2000). The throws on these faults are reported by stillwithintheLateMiocene.
Bunburyetal.(2001)tobegenerallylessthan100mbasedupon A final phase of tectonic deformation is attributed to the
the offset of the Ulubey Formation. These offsets undoubtedly Pliocene-Quaternary. This phase of north-south extension was
created significant topography across the former Miocene lake responsibleforthecreationoftheE-Wstrikinghighanglenormal
floor, which would have promoted drainage development. A faultsthatboundtheAlas¸ehir(Gediz)Grabentothesouthofthe
numberoftheseNNE-SSWtrendingfaultscutacrossthestudyarea study area. Bozkurt (2001) suggests that this latest phase of
and theirexhumation oftenappears toguide contemporaryriver extensionbeganintheearlyPliocene,~5Ma,withaccelerationof
courses(Fig.4a). movement on the Alas¸ehir graben bounding faults during the
_
Unconformably overlying the Inay Group is the Kocakuz Quaternary at ~1.6 Ma suggested from the biostratigraphy of
292 D.Maddyetal./QuaternaryScienceReviews166(2017)289e306
Fig.2. SimplifiedgeologyoftheGedizRiverBasinshowingthelocationoftheNeogeneBasinsandtheirrelationshiptothebasementrocksoftheMenderesMassif.Basaltsshowthe
approximateextentoftheKulaVolcanicProvince.DashedboxshowstheapproximatepositionofFig.3.
uplifted sediments (Sarıca, 2000). Significant E-W trending high- relativeupliftinthestudyarea,forcingthesubsequentprogressive
angle (>35(cid:1)) normal faults attributed to the late Miocene-early incision into the basin fill. The forces that triggered incision are
Pliocenehave been identified northof the studyareain thecen- ongoingatpresent,ensuringcontinuingadjustmentofthefluvial
tralSelendiBasin,wheretheyboundasymmetricalgrabensupto system.DynamicaladjustmentoftheGedizRivertoupliftduring
~10kmwide(Fig.2;Seyitog(cid:1)luetal.,1997; PurvisandRobertson, the Quaternary is complicated, not only by the frequency of
2004). Purvis and Robertson (2004) report that these faults, changing environmental conditions that control sediment and
whichindividuallytypicallyhave<20moffsets,cutallsedimentary water availability, but also by localized disruptions to water and
units and therefore cannot be dated accurately. They also state, sediment supply caused by volcanism, lake formation and land-
however, based upon the work of Seyitog(cid:1)lu et al. (1997), Yilmaz sliding(Maddyetal.,2012b).
etal.(2000,2001)andWestaway(pers.comm.2004),thatthese
faultspre-dateallQuaternary-agelavaflows. 3. QuaternarygeologyandtheGedizValleyFormation
Thisfinalphaseoffaultingwould,asinthecaseoftheearlier
LateMiocenefaulting,haveexertedfurtherstructuralcontrolover The mapped Quaternary deposits of the study region are
anyevolvingdrainagepattern.ThepatternofPliocenedrainagein dominatedbythebasalticlavaflowsoftheKulaVolcanicProvince.
the area is, however, unclear and connectivity between the PriortotheGedizRiverProject,achronologyoftheKulaVolcanic
drainage in the Selendi Basin and the Alas¸ehir graben uncertain. Province was proposed based upon a small number of K-Ar age
The sediments attributed tothe Asartepe Formation in the study estimatesandclassificationofflowsintoarelativesequenceonthe
area byErcan etal. (1983)mayrelate tothis time interval.How- basisoftopographicexpressionandtheweatheringcharacteristics
ever, there is little observational data reported in the literature of the observed lava flows (Erinc,1970; Ercan,1993. Ercan et al.,
andtheirstratigraphicalrelationshiptotheQuaternarybasaltsis, 1983,1996).Theflowswerecategorizedintofourgroupingsß1-
at best, ambiguous. What is clear, however, is that the Late ß4withß1theoldestandß4theyoungest.Onlylavaflowsrelating
Miocene-Pliocene reorganisation of drainage is triggered by the togroupsß2-ß4wereidentifiedinourstudyarea.Basaltscappinga
deformation associated with regional tectonic extension. This number of high level plateaus e.g. the Burgaz, Sarnıç and
deformation produces a regional gradient that ultimately forces I_brahimag(cid:1)awereattributedtotheß2group(Fig.3).Theyoungest
water out of the Selendi Basin towards the evolving sink of the andfreshestbasaltswereattributedtotheß4groupandallbasalts
Alas¸ehir (Gediz) Graben. Differential crustal movements result in at heights intermediate between the two, and more weathered
D.Maddyetal./QuaternaryScienceReviews166(2017)289e306 293
Fig.3. Generalizedgeologyofthestudyarea(basedonErcanetal.,1983withmodifications).CoordinatesareUTMZone35.
Table1
GeneralCenozoicstratigraphyofthestudyarea(afterErsoyetal.,2010;Maddyetal.,2012a).
Quaternary Pleistocene GedizValleyFormation Kulavolcanics
Tertiary Pliocene ?AsartepeFormation
Late Kabaklarbasalt
KocukuzFormation
_
Middle InayGroup OrhanlarBasalt
UlubeyFormation
Miocene Yag(cid:1)cıdag(cid:1)Volcanics
AhmetlerFormation
Early HacıbekirGroup Kürtko€yüFormation
Yeniko}yFormation
than the youngest grouping, were attributed to the ß3 group differenteruptioncentres.Thosefurthestnorth,nowonoraround
(Fig.3).AK-Arageestimateof1100ka(Borsietal.,1972;noerror the basaltic plateaux were the oldest, with highly degraded vol-
margingiven)fromaß2flow(samplinglocationisuncertain)inthe canicconesorexposedvolcanicnecks.Thevolcaniccentresforthe
studyarea was Early Pleistocene in age, thus establishing a Qua- Middle Pleistocene eruption centres lay further south and their
ternaryassignmentforallofthebasaltsofthestudyarea. flowsoccurredatloweraltitudinallevels.Finally,themostrecent
Additionalageestimateswerereportedforanumberofflowsby eruptioncentreslayevenfurthersouthandaresituatedclosestto
Richardson-Bunbury (1992) and these largely confirmed the theAlas¸ehir(Gediz)grabenandareevidencedbylargeconesand
existing subdivision suggesting that the flows in our field area lava flows with relatively fresh, irregular surfaces. Some of these
representedthreediscretephasesofvolcanicactivity.Basaltsam- flowsreachthecurrentGedizRivernorthofKula(Fig.3).
ples taken in the early years of our Gediz River Project yielded AlthoughtheworkofBunburyacknowledgesanassociationof
furthergeochronologicalresolution(Westawayetal.,2004,2006; the lava flows north of Kula with underlying fluvial sediments
see Table 4) suggesting that these aforementioned phases of vol- (Bunbury et al., 2001), this work, which was largely based on a
canic activity related to the Early, Middle and Late Pleistocene petrologicalandchemicalstudyofthelavas(Richardson-Bunbury,
respectively. Geographically each phase was related to a zone of 1992, 1996), failed to recognise the full complexity of the
294 D.Maddyetal./QuaternaryScienceReviews166(2017)289e306
Fig.4. A.MapoftheburiedEarlyPleistoceneterracesGT11-GT1baseduponMaddyetal.(2012a).Alsoshownarethesamplinglocationsforthe40Ar/39Arageestimates(A-M)and
thepalaeomagneticsamplingKU1-KU14.Newsamplesreportedhereforthefirsttimeareshowninbold.Asimplifiedsection(a-b)showingthesteppedAhmetler-Gedizgravel
contact(GTterracebases)ontheBurgazplateauisshowninBbelow.
underlying sequence and thus arrives at conclusions which are widebutasthesearetruncated,thewidthoftheformerfloodplains
readily refuted by the later Gediz Project observations. Similarly, isunknownbutlikelytobelessthan500m.Thepreservationof
onlysomeoftheageestimatespresentedbyWestawayetal.(2004, theseterracedepositsisclearlytheresultoftheirfortuitousburial
2006)relatetolavaflowsthathaveaclear,unequivocal,relation- beneaththeerosion-resistantcappinglavaflows(Fig.5c).Dissec-
shiptotheunderlyingfluvialdeposits,thuslimitingtheirutilityin tionoftheareanorthoftheBurgazplateaueliminatesanyoppor-
establishing a secure chronology for the underlying fluvial tunityforthepreservationofhigherterraceunitsnorthofthelava-
sequence. cappedterraces.Itislikely,however,thattheformationandpres-
TheearlyyearsoftheGedizRiverProject(2001e2004)identi- ervationofterraceswasrestrictedtopalaeo-valleyfloorsdeveloped
fied previously unrecognised complexity within the buried Qua- onthereadilyerodibleAhmetlerFormation.Thelessreadilyeroded
ternary fluvial sedimentary sequence beneath the high level calcareous beds of the Ulubey Formation currently allow only
basalticplateaux.Usingdetailedtraditionalsurveymeasurements narrow and steep-sided valleys to form, a poor environment for
ofcriticalcontacts,Maddyetal.(2005)identifiedeleventerracesof terrace preservation. The highest terrace has a base below the
the Gediz River preserved beneath the basalt-covered Burgaz Burgaz plateau at an altitude of ~615 m a.m.s.l., which is within
plateau, with each discrete Gediz terrace (GT) designated by a 30moftheAhmetlerFm./UlubeyFm.contactexposedinthescarp
numberfromGT1thelowestandyoungest,toGT11thehighestand tothenorth,therebysuggestingthattheareabetweentheBurgaz
oldest(Fig.4aandFig.5aec).Theterracedepositslieaboveplanar, plateauandthecurrentscarp(Fig.3)couldhavesupportedonlya
near-horizontal,contactswiththeunderlyingAhmetlerFormation limited number of additional higher terraces prior to dissection.
(Figs. 4b and 5b). These bases have lateral extents up to ~200 m However,ourobservationssuggestthisareamayhavealreadybeen
D.Maddyetal./QuaternaryScienceReviews166(2017)289e306 295
Fig.5. Exampleoutcrops.A.GeneralviewofexposuresalongthewesternedgeoftheBurgazPlateaux.B.GT5gravelsoverlainbytributarygravelandcolluvialsediments(closeto
40Ar/39ArsampleB,Fig.4a).C.GT9Gedizgravelsoverlainbytributarygravelsandavolcaniclasticsequence(closeto40Ar/39ArsampleE,Fig.4a).D.Intercalatedlacustrineand
water-laintephraontheSarnıçplateaux(sampleliesabovepresumedGT7gravelsjustnorthofKU19Fig.4a).
considerably deformed due to faulting (see below), making it Burgazplateau,GT6sedimentsareoverlainbylacustrinesediments
highlylikelythattheGT11terraceistheearliestpossiblepreserved thatonlaptheolderterraces(uptoGT9),suggestingtheformation
terraceofthepalaeo-GedizinthispartoftheGedizcatchment. of a large standing water body. The GT6 valley floor was thus
Usinggradientprojectionofterracebases,theseoutcropswere blockeddownstream,withavolcanicdamcausedbylavaincursion
correlatedwithsimilarfluvialsedimentsdownstreambeneaththe ontothevalleyfloorbeingthemostlikelyscenario.
basalt-capped Sarnıç plateau (Fig. 4a). Later mapping work Maddy et al. (2012a) suggest this initial volcanic dam was
(2005e2011)downstreamoftheoriginalfieldareaidentifiedGediz associated with the emplacement of lavas that cover the
gravels beneath the basalt-capped I_brahimag(cid:1)a plateau (Fig. 4a). I_brahimag(cid:1)aplateauandtheyspeculatedthatthemostlikelysource
These new data required a re-evaluation of the original assumed was theTavs¸anvolcanicneck(no.1, Fig.3).Lacustrine sediments
river gradient used for correlation of the terrace bases. The new depositedwithinthelakeassociatedwiththisdam(Lake1,Maddy
highergradients(~0.004e0.005)wereconsistentwiththemodern et al., 2012a) cover Gediz terrace sediments across much of the
rivergradientandasaresult,arevisedcorrelationmodelforthe higherlevelsoftheBurgazandSarnıçplateaux.Thicktephrabeds
outcrops was proposed (Fig. 6, after Maddy et al., 2012a). The intercalated with lacustrine sediment of the same lake on the
recognitionthatthedepositsofthepalaeo-Gedizrivercould,onthe eastern exposures of the Sarnıç plateau (Fig. 5d) suggest a more
basisoftheirlithologicalcompositionandsedimentaryproperties, localsourcefromtheToytepeneck(no.3,Fig.3)andthepresenceof
bereadilymappedanddistinguishedfromallotherstratigraphical pillow structures in the lavas that cap Kavtepe suggest that this
units led Maddy et al. (2012a) to propose that these distinctive neck (no.5, Fig. 3) may also have erupted directly into this lake.
sedimentsshouldbeformallyrecognisedastheGedizValleyFor- Thick (>50 m) tephras close to the Sarnıç Bag(cid:1)tepe volcanic neck
mation. The numbering of individual terraces remains only an (no.4, Fig. 3) may also suggest eruption of that neck during this
interim measure, each of these stratigraphical units will be period. This stratigraphy suggests that the first eruptions came
replaced with appropriate Member names once work on the from volcanic centres situated either within or close to the
completeGedizValleyFormationi.e.includingourongoingstudy I_brahimag(cid:1)aplateauwitheruptionsfocusedaroundtheBurgazand
oftheMiddleandLatePleistocenefluvialunits,iscompleted. Sarnıçplateauxfollowingshortlyafterwards.
Detailedobservationsoftheterracesedimentstakenfrom>100 Establishingtheageofthefirsteruptionwouldprovideacritical
separate outcrops exposed along the dissected margins of the pinningpointfortheterracesequencebyprovidingaminimumage
plateau, demonstrate clear stratigraphical relationships between fortheGT11-GT6sequenceandamaximumagefortheGT5-GT1
theterracesandtheearliestphaseofvolcanismwithinthispartof sequence. Several attempts to obtain an 40Ar/39Ar age estimate
theKulaVolcanicProvince.Theonsetoflocalvolcanismissignalled fromtheTavs¸anlavaimmediatelyadjacenttotheneckhaveproved
bya change in lithological content with the influxof substantive indeterminate. Westaway et al. (2006) report an age estimate of
quantitiesofbasaltintotheriverbedloadpostGT6(Maddyetal., 1264±15kaforalavaflowthatcapstheÇakırcasequence.Thislava
2012a). This conclusion is further supported by the stratigraphy flowdoesnotdeformtheunderlyingstandingwatersedimentsand
ofkeyGT6exposuresbeneathboththeBurgazandSarnıçplateaux. thusappearstoarriveafterthelake(Lake1)hasdrained.Onthis
BeneaththeSarnıçplateau,thesedimentologyofGT6depositsnear basis, Maddy et al. (2012a) concluded that the earliest damming
Çakırca (Fig. 3; see also Fig. 9A in Maddy et al., 2012a) strongly event must pre-date~1264ka (MIS38,Lisiecki and Raymo, 2005).
suggestsdepositioninstandingwater,aconclusionsupportedby Byinference,Maddyetal.(2012a)thusalsoconcludedthatGediz
thepresenceofthicklacustrinesedimentsthatincludesubstantive terracesGT11-6mustalsopre-datethistime.
amounts of tephra in adjacent exposures. Similarly, beneath the Theregularaltitudinalseparationbetweenthebasesofthehigher
296 D.Maddyetal./QuaternaryScienceReviews166(2017)289e306
Fig.6. TerracebaselongitudinalprofilesforterracesoftheGedizValleyFormation(Maddyetal.,2012a).Samplepointsrepresentaccuratelysurveyedheightmarkingthecontact
betweenGedizRivergravelsoftheterracesandtheunderlyingAhmetlerFm.Shadedboxessignifytheapproximateextentofthehighlevelbasalticplateaux.
terraces(GT11eGT6)suggestedacycliccontrolovertheirformation locations(Fig.4a,KU1-8)wereusedtoestablishtheageofahominin
(Maddyetal.,2005).TerracesGT11-GT7allhavecolluvialsediments artefact (Maddyet al., 2015) found within fluvial sediments post-
overlying the fluvial deposits, which record post-abandonment dating the lava flows overlying the GT1 level sediments on Kale
environmentalchangespriortotheirburialbyeitherlacustrineor Tepe (Fig. 3) and those same age estimates were also used in a
volcaniclasticdeposits.Thesecolluvialsequencescontainnumerous detailed discussion of the palaeoenvironmental implications of a
palaeosolsthatrecordcyclicchangesalternatingbetweenwetterand colluvial-fluvialsequencelyingabovetheGT11levelonthenorthern
dryerconditions,thelatterfrequentlyassociatedwithcalcretefor- limitoftheBurgazplateau(Veldkampetal.,2015).Here,forthefirst
mation(Maddyetal.,2012b;Veldkampetal.,2015).Thethickness time,wewillpresentthefulldataset,whichincludesunpublished
andcomplexityofthesecolluvialsequencesisgreatestonGT11(up ageestimatesfromsixadditionallocalities(Fig.4a,H-M)andsixnew
to ~5 m thick), diminishing progressively in both thickness and palaeomagneticdeterminationscriticaltoourunderstandingofthis
stratigraphicalcomplexitymovingdowntheterracesequencetoGT7 sequence(Fig.4a,KU9-KU14).Afterdescribingthesemeasurements,
wherethesedepositsare<2minthickness.Veldkampetal.(2015) theimplicationsofthesenewdatawillbediscussed.
link the environmental changes recorded in these colluvial se-
quencestoEarlyPleistoceneclimatecyclesandsupporttheearlier 4. Establishingarefinedchronologyforthelavaflowsofthe
suggestion of Maddy et al. (2005) of a direct link between cyclic BurgazandI_brahimag(cid:1)aplateau
climatechangeandterraceformation.Maddyetal.(2005)suggest
thatthesecyclesweremostlikelytheobliquity-drivenclimatecycles 4.1. Methods
recognised from Eastern Mediterranean ocean oxygen isotope re-
cords(Kroonetal.,1998). Ourprogrammeofgeochronologicalinvestigationinvolvedboth
Thelowerterracesequence(GT5-GT1)demonstrablypost-dates 40Ar/39Ar radio-isotopic measurement for age estimation and
GT6.Inanattempttoputaminimumageontheterracesequence, palaeomagnetic measurements focused on establishing polarity.
Maddyetal.(2012a)inferredthatalavaflowthatcoverstheeastern 40Ar/39Ar measurements were undertaken at the VU University,
sideoftheI_brahimag(cid:1)aplateau,withtheyoungestavailableagees- AmsterdamandpalaeomagneticmeasurementsatUtrechtUniver-
timateof~999±21ka(Westawayetal.,2006),may,onthebasisofits sity. Our sampling strategy was primarily designed to sample
altitude,haveenteredtheGT1valley.However,therearecurrentlyno basaltic lava flows with clear stratigraphical relationships to the
recordedexposuresofsedimentsontheI_brahimag(cid:1)aplateauthatcan underlyingGedizValleyFormationorflowswithacleartermination
besecurelycorrelatedwithGT1,thustherelationshipofthisflowto atcontemporarypalaeo-Gedizvalleyfloorlevel.Inaddition,how-
theterracesequenceissomewhatequivocal.Despitethiscomplica- ever, two samples were taken from isolated basalt boulders in
tion,Maddyetal.(2012a)assignedGT1toMIS28.Thisattributionled attempt to establish their provenance. Sample locations for both
Maddy et al. (2012a) to the conclusion that terraces GT5-GT1 40Ar/39Ar (A-M) and palaeomagnetic measurements (KU1-KU14)
continued to reflect formation synchronous with climate change areshowninFig.4a.
despite the obvious disturbance to the fluvial system by repeated
volcanicdamming(evidencedbylakesedimentsdrapedacrossthe 4.1.1. 40Ar/39Arsamplingandprocedures
youngerterraces),lakedrainageandtheinfluxofvolcanicproducts Groundmassseparateswerepreparedusingawell-established
duringthisinterval(Maddyetal.,2012b). methodologywhichisdesignedtoobtainhomogenousfragments
Since2012,ourextensiveprogrammeof40Ar/39Arradio-isotopic of microcrystalline groundmass and thus minimize the potential
geochronologyand palaeomagnetic measurements oncriticallava for inherited argon within the phenocryst phases. Groundmass
flowshasyieldedresultsthatrequireustore-evaluatethestratig- samples (~500e700 mg) were packedin 20 mm diameter Al-foil
raphy published in Maddy et al. (2012a). Seven of these new age packages, together with 9 mm diameter packages containing
estimates (Fig. 4a, A-G) and associated magnetic data from eight mineralstandardFCsanidine.ThisstandardhasarecalculatedK/Ar
D.Maddyetal./QuaternaryScienceReviews166(2017)289e306 297
age of 28.201 Ma (Kuiper et al., 2008). Only sample K has been magneticpolaritiesindicatedbytheChRMdirectionswerechecked
packedwithmineralstandardDRA-1sanidine.Samplecontainers forbeingconsistentwiththegeomagneticpolaritytimescale(APTS
werepackedinastandardAl-irradiationcapsuleandirradiatedfor (astronomical polarity timescale), 2012: Hilgen et al., 2012).
1hinaCd-linedrotatingfacility(RODEO)atthePettenHighFlux DetailedresultsfromtheseanalysesareprovidedinsupplementS2.
ReactorinTheNetherlands.Sampleswerethenloadedontoa65-
mm sample tray with 5 machined depressions (3 mm deep and 4.2. Results
17mmwide)andplacedinavacuumhousewitha50mmdiameter
multispectral ZnS window. Incremental heating was done by Summary data for the 40Ar/39Ar radio-isotopic measurements
defocusingaCO2laserbeamtoa~2mmstraightbarusinganin- andcalculatedageestimatesareshowninTable2.Summarydata
dustrialscanheadwithatriangulardeflectioncurrentfrequencyof for the palaeomagnetic measurements are shown in Table 3. In
200Hz.Sampleswereevenlyheatedbyapplyingafinex-yraster ordertosimplifydiscussionsampleresultswillbediscussedwith
pattern over each of the sample positions. Measurements were respecttolocationbut,wherepossible,instratigraphicalorder.All
done using a quadrupole mass spectrometer (Schneider et al., samplelocationsareshownonFig.4a.
2009). Mass spectrometer runs consist of stepwise measurement
oftheargonmassspectrumfromm/e36tom/e40,whereonm/e 4.2.1. 40Ar/39Arradio-isotopicmeasurements
36,39and40sevenreadingsweretakenat0.05m/eintervalson 4.2.1.1. Sites H, I and J (I_brahimag(cid:1)a plateau). The oldest age esti-
the flat peak top, and for m/e 37 and 38 one single reading was mates within our current data set come from the I_brahimag(cid:1)a
taken.Thebaselinewasmeasuredatm/e35.45.Beamsignalsforall plateau. Two samples from location H yielded separate age de-
peaks were measured using a pulse counting SEM detector. Ali- terminations of 1097 ± 99 ka and 1470 ± 97 ka respectively
quotsofairaremeasuredroutinelyduringthemeasurementpro- (Table2).However,takentogether,thesesamplesyieldameanage
gramme to monitor mass discrimination (Wijbrans et al., 2011). of1272±80ka.Theseestimateshaveverylargeuncertainty(see
DetailedresultsfromtheseanalysesareprovidedinsupplementS1. supplement S1). The base of the sampled outcrop lies at ~490 m
40Ar/39Arageswerecalculatedwiththefreewaresoftwarepackage a.m.s.l.andtheunderlyingAhmetlerFormationisobservedinan
ArArCalc (Koppers, 2002), which follows standard protocols for immediatelyadjacentoutcrop.Thesurfacetopographyofthislava
uncertaintycalculation.ForpresentingQuaternarybasaltground- flow suggests a derivation from the east, higher up on the
masssampleswequotetheuncertaintiesataonesigmalevel. I_brahimag(cid:1)aplateau.AlthoughnoGedizterracegravelsareobserved
here,thealtitudeof~490misconsistentwiththisflowterminating
4.1.2. Palaeomagneticsamplingandprocedures attheGT6valleyfloorlevel(Fig.6).
Atotalof96samplesfrom14lavasites(KU1eKU14,Fig.4a)on BasaltssampledatlocationsIandJwerederivedfromoutcrops
theplateauwerecollectedusingawater-cooled,gasoline-powered, which have previously been assigned a ß3 age by Bunbury et al.
motordrill.ResultsofsitesKU1throughKU8havebeenshownand (2001), presumably on the basis of their comparatively low alti-
discussedinMaddyetal.(2015),hereweprovidetheresultsofsites tude i.e. ~50 m beneath the flows covering the adjacent plateau.
KU9-14.Sampleswereorientedwithamagneticcompassandall Our field observations, however, could notestablish a clear basal
magnetic measurements were corrected for the present-day contactwiththeunderlyingAhmetlerFormationandtheoutcrop
declination of ~4(cid:1). All samples were stepwise progressively terminatedabruptlytothesouthcoincidingwithamoderngulley
demagnetizedupto100mTwithalternatingfield(AF)increments orientated in an ENE-WSW direction. Based upon these observa-
of 5e10 mT. After each step, the remaining natural remanent tionsweinterpretthisoutcropasanewlyrecognisedvolcanicneck
magnetization (NRM) of the specimens was measured on a 2G referredtohereasAkçes¸me(no.8,Fig.3).Theagedeterminations
Enterprises horizontal DC SQUID magnetometer (noise level of1327±11ka(I)and1298±13ka(J)suggestthisbasaltoriginated
3 (cid:3) 10e12 Am2), interfaced with an in-house developed robot- duringtheearliestphaseofvolcanismontheI_brahimag(cid:1)aplateau
assisted automatedmeasuringdevice at the Palaeomagnetic Lab- (Table2).Thisageassignmentcannotbereadilydismissed.Thereis
oratory ‘Fort Hoofddijk’ of Utrecht University (The Netherlands). noobviouslinkage,otherthanheight,forthisoutcropwithß3lava
InitialNRMintensitiestypicallyrangefrom0.5to2.0A/m,atthe outcropsfurthereast.Theobviousheightdifference,withnoevi-
upper end of the dynamic range of the instrument (lightning- denceofdisplacementofthebasalt,doeshoweverrequireexpla-
affectedsamplesgoupto~75A/m).Forinterpretation,demagne- nation(seebelow).
tization diagrams of the NRM were plotted on orthogonal vector
diagrams (Zijderveld, 1967). When vector end-points showed a 4.2.1.2. Sites A, B (Burgaz plateau). Although eruptions in the vi-
trend towards the origin of the diagram, we determined this cinityofthecurrentI_brahimag(cid:1)aplateauappearstobetheearliest
component to be the characteristic remanent magnetization eruptioncentres,theyarequicklyjoinedbyeruptionsfromBurgaz
(ChRM).ChRMswerecalculatedwithprincipalcomponentanalysis Bag(cid:1)tepe. Basalts from location A yielded an age estimate of
(Kirschvink,1980).Becausetheplateauswherethesampleswere 1297±17ka(Maddyetal.,2015).Thissampleliesdirectlyabovea
collected are prone to lightning strikes, which create magnetic thickcolluvialsequencedescribedbyVeldkampetal.(2015),which
overprints,sampleswerecollectedoveranareaofseveraltensof inturnoverliesGT11,thehighestGedizterracethusfarrecognised.
squaremetrestoincreasethechancethatlightning-inducedover- Thepalaeo-Gedizvalleytowardswhichthislavamostlikelyflowed
prints have different directions in different samples. Where a isindeterminateasitmergeswithmorerecentflowssouthofthe
magnetic overprint led to overlapping demagnetization spectra outcrop. Basalt sampled at location B yielded an age estimate of
between two components we used the great-circle approach of 1287±25ka(Maddyetal.,2015),whichmayormaynotrepresent
McFadden and McElhinny (1988) to resolve the ChRM direction thesamelavaflowasA.
fromthegreatcirclesdefinedbythetwocomponentsforindividual
specimens from the same site. If the overprint direction is not 4.2.1.3. SiteK(isolatedboulder). Alargeisolatedblockofbasaltat
everywherethesame,theChRMdirectioncanbededucedbythe locationKyieldedanageestimateof1325±43ka(Table2).The
commonintersectionpointofallgreatcirclesobtainedfromalava locationandageofthisbouldersuggestsitisderivedfromoneof
site,withtwosolutions(onenormal,onereversed),wherebythe theearliesteruptions.Thiscouldbeanisolatedremnantofalava
polarityisdeterminedbynon-oronlyweaklyoverprintedsamples flowlargelyremovedbysubsequenterosionorpossiblyitisasso-
withinthesamesite.Withtheradiometricageoftheflowsknown, ciatedwiththepost-Lake1lakelavaflowwhichcapstheÇakırca
298 D.Maddyetal./QuaternaryScienceReviews166(2017)289e306
Table2
40Ar/39Ardatasummarytable.SamplelocationsareshowninFig.4a.SamplesA-GwerepreviouslypublishedinMaddyetal.,2015.SamplesH-Marenewdatapublishedhere
forthefirsttime.
Name Sample Labcode Plateauage(ka) 1s MSWD N.Isochronage(ka) 1s Inv.Isochronage(ka) 1s
A 03EBurgazNo(above47) VU87WG3_A2 1299.2 17.2 0.50 1288.3 22.1 1290.9 22.0
B 02RBurgazwest VU87WG2_B1 1286.9 25.2 0.71 1277.5 27.0 1280.9 27.2
Ci W6_K2 VU94W6_1_B1 1265.9 17.8 1.57 1180.8 53.3 1181.4 53.1
Cii 03cKaleTepe VU87WG3_B1 1251.0 25.2 6.28 1263.2 29.7 1263.9 29.4
C CiandCiicombined e 1255.8 16.0 3.73 1258.8 23.0 1259.7 22.5
D W4_BW1 VU94W4_1_C2/VU94W5_2_B3 1241.1 9.3 1.90 1214.1 13.4 1217.0 12.7
CandDcombined e 1246.6 8.2 2.61 1239.4 10.6 1242.2 10.4
E W11_BW2 VU94W11_1_B1 1170.2 9.7 0.62 1163.8 20.6 1166.0 20.3
F GB2Ziftce VU87WG2_B3 1254.8 17.4 1.26 1242.4 18.6 1249.4 19.2
G GB4Delihasan VU87WG2_A2 1239.8 60.4 0.62 1235.2 145.1 1234.2 139.4
H IW2 94W5_1_C2 1097.9 98.8 2.27 882.0 165.1 901.9 144.0
94W2_2_A2 1470.1 97.4 2.15 1153.7 355.5 1178.6 257.3
IW2combined e 1272.4 80.0 2.94 962.0 163.3 993.3 130.5
I 645 94W9_1_C2 1327.0 11.0 0.65 1280.9 35.7 1281.2 35.4
J 653 94W10_1_B3 1297.1 13.4 0.53 1270.8 20 1274.1 19.4
645/653combined 1315.0 8.5 0.7 1274.3 16.8 1276.8 16.5
K 349 WG3_C2 1324.6 42.4 1.07 1284.1 64.2 1287.4 64.5
L IW1 94W8_1_B2 1082.0 14.7 1.40 1003.4 22.0 1005.3 21.8
M IE1 94W1_1_B1 1101.8 18.8 1.48 1041.9 25.8 1043.8 25.6
94W4_3_C2 1017.9 19.3 0.53 998.1 44.7 999.2 44.6
CombinedIE1 e 1069.0 15.8 1.72 1010.0 18.3 1013.4 18.3
Table3
Palaeomagneticresultsandstatisticalpropertiesofthe14sitesinKulabasalts.Lat¼latitudeofthesite;Lon¼longitudeofthesite;Typeindicates‘gc’whenthesiteaverage
wasconstructedusingthegreatcirclemethodofMcFaddenandMcElhinny(1988);Na¼numberofsamplesanalysed;Nc¼numberofsampledusedtoconstructthesite
average;k/K¼Fisher(1953)precisionparameterforthesite/VGPaverage,respectively;a95/A95¼95%confidencelimitofthesite/VGPaverage,respectively;D¼declination;
DDx¼95%confidencelimitofthedeclination;I¼inclination;DIx¼95%.Sites1e8,markedwith*,werepreviouslyreportedbyMaddyetal.(2015).
Locality Lat Lon Type Na Nc Tiltcorrected Polarity
Lava/necksite D DDx I DIx k K a95 A95
Kula:All 14 12 199.1 12.8 ¡64.9 6.7 25.7 8.7 Reversed
KU1* 38.6301 28.8128 gc 7 7 215.8 (cid:4)69.7 87.8 6.5 reversed
KU2* 38.6199 28.8133 7 6 214.0 (cid:4)69.7 1446.2 1.8 reversed
KU3* 38.6129 28.7943 gc 7 6 221.7 (cid:4)80.5 86.6 7.2 reversed
KU4* 38.6129 28.7943 gc 7 6 200.8 (cid:4)64.1 58.8 8.8 reversed
KU5* 38.6129 28.7943 7 inconclusive:bothnormalandreversed.Seetext
KU6* 38.6103 28.7717 gc 7 5 209.0 (cid:4)69.8 108.2 7.4 reversed
KU7* 38.6102 28.7697 gc 7 7 191.4 (cid:4)47.8 382.1 3.1 reversed
KU8* 38.6353 28.7660 gc 7 7 179.5 (cid:4)51.5 479.2 2.8 reversed
KU9 38.6219 28.7637 gc 7 7 236.9 (cid:4)76.8 102.3 6.0 lightning
KU10 38.6253 28.7407 7 7 182.6 (cid:4)74.1 201.3 4.3 reversed
KU11 38.6561 28.6791 gc 7 6 201.2 (cid:4)69.6 251.9 4.2 reversed
KU12 38.6561 28.6791 7 7 185.4 (cid:4)60.3 119.0 5.6 reversed
KU13 38.6561 28.6791 gc 6 5 222.6 (cid:4)63.7 436.1 3.7 reversed
KU14 38.6328 28.67685 6 6 197.1 (cid:4)50.0 763.0 2.4 reversed
sequencedatedbyWestawayetal.(2006)to1264±16ka. 4.2.1.5. SitesFand G (Delihasan). Maddyetal.(2015)reportsam-
ples from locations F and G, which relate to eruption from the
Delihasan volcanic neck (Fig. 3). These yielded age estimates of
1255 ± 17 ka and 1240 ± 60 ka respectively (Table 2). The ages
4.2.1.4. Sites Ci, Cii, D and E (Burgaz plateau). Maddyetal.(2015)
support contemporaneous activity of the Burgaz Bag(cid:1)tepe and
reported a series of age estimates from the southern sections of
Delihasannecks.AlthoughsampleFistakenfromlavathatoverlies
theBurgazplateauwherethelavascoverthedepositsofGT5-GT1.
GT4 on ZiftçiTepe (Fig. 3), it is unclear whether thatflowtermi-
Samples from Kale Tepe at Ci and Cii yielded age estimates of
1266±18kaand1251±25karespectivelyandwhenconsidered natedatthatlevel.
togethertheseyieldanestimateof1256±16ka(Table2).TheKale
TepelavaliesaboveGT1.AfurthersamplefromlocationDyielded 4.2.1.6. SitesLandM(I_brahimag(cid:1)aplateau). Theyoungestlavaflow
anestimateof1241±9ka,Maddyetal.(2015)consideredthistobe ageestimatesreportedhereallcomefromtheI_brahimag(cid:1)aplateau.
fromthesamelavaflowthatcapsKaleTepeandthuscombinedall FlowsemanatingfromtheI_brahimag(cid:1)aBag(cid:1)tepevolcanicneckflow
oftheseagestoderiveanoverallestimatedmeanageof1247±8ka bothwestandeastaroundtheearlierTavs¸anflows.Aflowtothe
for the flow. Continuing eruption of the Burgaz Bag(cid:1)tepe volcanic west of Tavs¸an (L) yielded an age estimate of 1082 ± 15 ka and
neckissupportedbyanageestimatefromlavalocationE,which samples from a flow east of Tavs¸an (M) yielded age estimates of
yieldsanestimateof1170±9ka.Itisindeedpossiblethatfurther 1101±19kaand1018±19ka,whichwhencombined,yieldamean
eruptions continued well beyond this time as Westaway et al. ageof1069±16ka(Table2).Theseageestimatesareconsistent
(2006)reportanageestimateof1014±23kafromalavasample with the previously published age estimate of 999 ± 21 ka from
takensouth-eastoftheBurgazBag(cid:1)tepevolcanicneck. I_brahimag(cid:1)a east (Westaway et al., 2006). All of these lavas flow