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International Geology Review
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Geochemistry and tectonics of Cenozoic volcanism in the Lesser Caucasus
(Azerbaijan) and the peri-Arabian region: collision-induced mantle
dynamics and its magmatic fingerprint
Yildirim Dilek a; Nazim Imamverdiyev b; Şafak Altunkaynak c
a Department of Geology, Miami University, Oxford, OH, USA b Department of Geology, Baku State
University, Baku, Azerbaijan c Department of Geological Engineering, Istanbul Technical University,
Maslak Istanbul, Turkey
First published on: 10 November 2009
To cite this Article Dilek, Yildirim, Imamverdiyev, Nazim and Altunkaynak, Şafak(2010) 'Geochemistry and tectonics of
Cenozoic volcanism in the Lesser Caucasus (Azerbaijan) and the peri-Arabian region: collision-induced mantle
dynamics and its magmatic fingerprint', International Geology Review, 52: 4, 536 — 578, First published on: 10 November
2009 (iFirst)
To link to this Article: DOI: 10.1080/00206810903360422
URL: http://dx.doi.org/10.1080/00206810903360422

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InternationalGeologyReview
Vol.52,Nos.4–6,April–June2010,536–578
Geochemistry and tectonics of Cenozoic volcanism in the Lesser
Caucasus (Azerbaijan) and the peri-Arabian region: collision-induced
mantle dynamics and its magmatic fingerprint
Yildirim Dileka*, Nazim Imamverdiyevband S¸afak Altunkaynakc
aDepartmentofGeology,MiamiUniversity,Oxford,OH45056,USA;bDepartmentofGeology,
BakuStateUniversity,BakuAZ1148,Azerbaijan;cDepartmentofGeologicalEngineering,Istanbul
TechnicalUniversity,MaslakIstanbul34469,Turkey
(Accepted22September2009)
TheLesserCaucasusoccursinthehinterlandoftheArabia–Eurasiacollisionzonein
the broad Alpine–Himalayan orogenic belt and includes Cenozoic plutonic and
0
1
0 volcanic sequences that provide important clues for collision-driven continental
2

y magmatism and mantle dynamics. Two main magmatic episodes (Eocene and late
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a
u Miocene–Quaternary)formedthevolcaniclandscapeandtheigneousassemblagesin
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e theLesserCaucasusofAzerbaijan.(1)TheEocenesequenceconsistsoftrachybasalt
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5 and basaltic trachyandesite with subordinate tephrite-basanite, basaltic andesite, and
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9 trachyandesite,showingshoshoniticandmildlyalkalinecompositions.TheMiocene–
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7: Quaternarymagmaticepisodeisrepresentedby(2a)anearlyphaseofupperMiocene–
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: lowerPlioceneandesite,trachyandesite,trachydacite,daciteandrhyolitelavas,andby
t
A (2b)alatephaseofupperPliocene–Quaternarytrachybasalt,basaltictrachyandesite,
]
im basaltic andesite, trachyandesite, trachyte, and rhyolite flows. The rocks of the early
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di phasehavehigh-Kcalc-alkaline compositions,whereasthoseofthelatephaseshow
l
Yi high-Kshoshoniticcompositions,defininganalkalinetrendandaK2O-enrichedmelt
k, source. All three volcanic associations show variant troughs in Nb, Ta, Hf, and Zr,
e
il strongenrichmentinRb,Ba,Th,La,anddepletioninTi,Yb,Yrelativetomid-ocean
D
[ ridge basalt N-(MORB) in their multi-element patterns. The enrichment of
:
y incompatible elements and K suggests derivation from a metasomatized mantle
B

d source,whereasthetroughsinNbandTaindicateasubductioninfluenceinthemantle
e
d
a melt sources. Mantle-derived magmas were modified by AFC/FC processes for all
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n three volcanic sequences. These geochemical features are similar to those of coeval
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D volcanic associations in the peri-Arabian region, and indicate the existence of
subduction-metasomatizedlithosphericmantlebeneaththeLesserCaucasusduringthe
Cenozoic. Partial melting of this subduction-modified subcontinental lithospheric
mantle in the peri-Arabian region was triggered initially by slab breakoff following
discretecontinentalcollisioneventsintheearlyEocene.Theheatsourceforthelater
Miocene–Quaternary volcanism in the entire peri-Arabian region was provided by
asthenospheric upwelling, which itself was caused by delamination of the mantle
lithosphere following the final Arabia–Eurasia collision at ,13Ma. Increased
alkalinity of successively younger units in the Plio-Quaternary volcanic associations
resultedfromtheinputofenrichedasthenosphericmeltduringthelaststagesofpost-
collisional magmatism. Active, crustal-scale and orogen-parallel, transtensional fault
systems in the peri-Arabian region facilitated the formation of fissure eruptions and
stratovolcanoesinthelatestCenozoic.
*Correspondingauthor.Email:[email protected]
ISSN0020-6814print/ISSN1938-2839online
q2010Taylor&Francis
DOI:10.1080/00206810903360422
http://www.informaworld.com
International Geology Review 537
Keywords:LesserCaucasus(Azerbaijan);peri-Arabianregion;Turkish–Iranianhigh
plateau;post-collisionalmagmatism;slabbreakoff;lithosphericdelamination
Introduction
Cenozoicmagmaticrocksoccurextensivelyintheperi-ArabianregionnorthoftheBitlis–
Zagros suture zone (Figure 1), and they constitute a significant component of the
continentalcrust inthissegment ofthe Alpine–Himalayanorogenic belt.Although they
range in age from Eocene to Quaternary, their temporal distribution reflects significant
pulses of magmatism in the late Eocene, late Miocene–Pliocene, and Plio-Quaternary.
Thetimingoftheirformationmostlycoincideswithandpostdatesaseriesofcontinental
collisioneventsintheregion(DilekandWhitney2000,andreferencestherein).Together
withthenearly coevalvolcanic-plutonicunitsincentralandwestern Anatoliaandinthe
Aegean region to the west (Yılmaz 1989; Altunkaynak and Yılmaz 1998; Dilek et al.
0 1999b;Aldanmazetal.2000;Pe-PiperandPiper2001,2006;Yilmazetal.2001;Agostini
1
0
2 etal.2007;Altunkaynak2007;DilekandAltunkaynak2007,2009;KadiogluandDilekin

y
ar press),theCenozoicperi-Arabianmagmaticbeltispartofamuchlargerigneousprovince,
u
br which developed in a broad zone of convergence between Afro-Arabia and Eurasia
e
F
(Figure1;JacksonandMcKenzie1984;Deweyetal.1986;McCluskyetal.2000,2003;
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1
9 Allen et al. 2004; Dilek and Sandvol 2009). The melt sources of the Cenozoic peri-
0
7: Arabianmagmatismandthecausesofheatsupplythattriggeredmeltingareparticularly
1

: important questions for the geodynamic conditions and mechanisms that result in high-
t
A
] magmaticproductivity inpost-collisional orogenic belts.
m
ri TheEocenemagmaticunitsintheperi-Arabianregionareexposedinmainlynarrow,
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l E–W-trending, curvilinear belts that straddle the suture zones between the continental
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, blocks (Figure 2).These magmatic units include granitoid–syenitoid plutons and coeval
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le volcanic sequences intercalated with clastic–volcaniclastic rocks. Volcanic units have
i
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[ mildly alkaline, shoshonitic affinities and are overlain by late Eocene flysch deposits

:
By and/or late Miocene volcanic sequences. The next magmatic pulse in the region is

ed represented by upper Miocene–Pliocene volcanic sequences, occurring in the northern
d
a
o partoftheTurkish–IranianhighplateauandtheLesserCaucasus,whicharecharacterized
l
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w by calc-alkaline affinities reminiscent of extrusive rocks forming at active convergent
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margins(Pearce1982;Wilson1989;Thirlwalletal.1994).Thelatestmagmaticpulsein
thePlio-Quaternaryisrepresentedbyalkalinerocksthatoccupymuchofthesouthernpart
of the Turkish–Iranian plateau and the western Lesser Caucasus, and that show within-
plate basalt geochemical characteristics (Pearce et al. 1990; Yilmaz et al. 1998; Keskin
2003;Kheirkhahetal.2009).ThesevariationsinthelavachemistryofthelateCenozoic
volcanic rocks (Miocene to Quaternary) indicate a geochemical progression from calc-
alkaline to more alkaline compositions in time and a spatial shift from north to south
towardstheArabianplate.Thegeologicalfactorsthatcontrolledthetemporalandspatial
distribution of the Cenozoic magmatic rocks in the hinterland of the Arabia–Eurasia
collisionzoneandthemeltregimesandtectonicsettingsoftheirformationareoutstanding
questionsbothinthegeodynamicsoftheeasternMediterraneanregionandincontinental
magmatism inyoung orogenic belts.
Inthispaper,wepresentnewgeochemicaldatafromrepresentativeCenozoicvolcanic
sequencesintheLesserCaucasusofAzerbaijan,fillingamajorgapinourknowledgeofthe
post-collisionalmagmatismintheperi-Arabianregion,andweusethesedatatoinferthe
petrogenesisoftheserocksinordertointerprettheirmeltsourcesandmagmaticevolution.
538 Y. Dileket al.
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Y Figure2. TectonicmapoftheeasternMediterranean–PersianGulfregion,showingthemainplate
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k boundaries,collisionzones,distributionofNeotethyanophiolitesandEocenevolcanicsequences,
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il microcontinental fragments with Arabian affinity, and Tauride ribbon-continent with Gondwana
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[ (Afro-Arabian)origin.Majormagmaticbelts(i.e.Ahar–Arasbaran,Urumieh-Dokhtar)andvolcanic
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By units(i.e.Madencomplex,Kislako¨yvolcanics)discussedinthetextarealsoshown.CACC,Central

d Anatoliancrystallinecomplex;DSF,DeadSeafault;EAAC,EastAnatolianaccretionarycomplex;
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ad EAF,EastAnatolianfault;EF,Ecemisfault;IAESZ,Izmir–Ankara–Erzincansuturezone;ITSZ,
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nl Inner-Tauride suture zone; KOTJ, Karliova triple junction; MTJ, Maras¸ triple junction; MZMM,
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Do Mishkana–Zangezur metamorphic massifs; NAF, North Anatolian fault; SASZ, Sevan–Akera
suturezone.
We also describethe spatial and temporal distributionofthe Cenozoic volcanic rocks in
nearbyIran,Armenia,andeasternTurkey,andcomparetheirgeochemicalfeaturestothose
of the coeval volcanic units in Azerbaijan. Finally, we evaluate the petrogenetic and
tectonomagmaticevolutionoftheCenozoicmagmatismintheLesserCaucasusandinthe
R
Figure1. SimplifiedtectonicmapoftheeasternMediterranean–PersianGulfregion,showingthe
activeplateboundaries,plateconvergencevectors(ingreen)withrespecttofixedEurasia,andpost-
collisional volcanic rocks in the peri-Arabian region. Continental blocks with Afro-Arabian
(Gondwana)affinityareshadedinlightyellow.AF,Aksufault;ASF,Arasfault;BF,Burdurfault;
DSFZ, Dead Sea fault zone; EAF, East Anatolian fault; EF, Ecemis fault; EKP, Erzurum–Kars
plateau; HT, Hellenic trench; IAESZ, Izmir–Ankara–Erzincan suture zone; ITSZ, Inner-Tauride
suturezone;MTJ,Maras¸triplejunction;NAF,NorthAnatolianfault;NEAF,NortheastAnatolian
fault;PSF,Pampak–Sevanfault;TF,Tabrizfault;TGF,Tuzgo¨lu¨ fault.
540 Y. Dileket al.
peri-Arabianregion inasimplegeodynamicmodel,which wepresenthereasaworking
hypothesistobefurthertestedwithfuturestudiesparticularlyinIranandAzerbaijan.
Regional geology
Muchoftheperi-ArabianregionnorthoftheBitlis–Zagrossuturezoneisoccupiedbythe
Turkish–IranianHighPlateau,wherethemeansurfaceelevationisabout2–2.5kmabove
sea level with scattered Plio-Quaternary volcanic cones over 5km high (e.g. Mt Ararat;
Figure3;DhontandChorowicz2006).TheplateauisboundedonthenorthbytheEastern
Pontide arc and the Lesser Caucasus, and on the south by a series of continental blocks
including the Bitlis–Pu¨tu¨rge (B–P) massifs in Turkey and the Sanandaj–Sirjan (S–S)
massif in Iran (Figures 2 and 3). The basement geology of the plateau is composed of
ophiolites and ophiolitic me´langes, latest Cretaceous and Cenozoic flysch and molasse
deposits, and the eastward extension of the Tauride microcontinent in the Munzur
carbonateplatform and inthe South ArmenianBlock (Figure 2).
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ry EasternPontideblock
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br The Eastern Pontide block north of the Turkish–Iranian plateau mainly consists of a
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F south-facing Jurassic–Late Cretaceous volcano-plutonic arc that developed over a
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subduction zone dipping northwards (Yilmaz et al. 1997), and post-collisional Eocene
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7: volcano-sedimentaryunitsandplutons. Thecollisionofthe EasternPontidearcwith the
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: Eastern Tauride–South Armenian continental block in the early Eocene terminated the
t
A
subductionzonemagmatisminthePontidesandproducedextensiveflyschdepositswith
]
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ri intense folding inand across the collisionzone (Deweyet al. 1986).
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ek LesserCaucasus
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[ The Lesser Caucasusincludes the Transcaucasian Massif in the north, the Sevan–Akera

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By suture zone (SASZ)with ophiolite exposures in the centre, and the Miskhana–Zangezur

ed metamorphic massifs (MZMM) in the south (Figure 2), which represent a continental
d
a
o fragment(KhainandKornousky1997;Golonka2004).ACretaceousislandarccomplex
l
n
ow with calc-alkaline to alkaline extrusive rocks, and pyroclastic deposits, flysch units, and
D
marl-limestonerocksoccursnorthofthesuturezone.EoceneandPlio-Quaternaryvolcanic
and plutonic rocks are widespread in the Lesser Caucasus and are described in the next
section.TheTranscaucasianMassifincludesPan-Africanorogeniccrustintrudedbylatest
ProterozoictoPalaeozoicgranitoids,whicharemultiplydeformedandmigmatized,andby
JurassictoEarlyCretaceousplutonsrepresentingamagmaticarc(Zakariadzeetal.2007).
ThisarccontinuesintotheEasternPontideblockinthewest.TheTranscaucasianMassif
wasalreadyaccretedtothesoutherncontinentalmarginofEurasiaby350Ma.TheSASZ
includes Late Jurassic–Early Cretaceous suprasubduction zone ophiolites, which were
emplacedsouthwestwardsontotheMZMMbytheLateCretaceous(KhainandKornousky
1997).ThissuturezoneandtheophiolitescontinuenorthwestwardsintoArmenia,andthen
intonortheasternTurkey,wheretheyconnectwiththeIzmir–Ankara–Erzincansuturezone
(IAESZ)andtheNorthernNeotethyanophiolites(DilekandThy2006).TheMiskhana–
Zangezurmassifs consist oflate Proterozoic toearly Palaeozoic schist,amphibolite,and
marble units, unconformably overlain by Devonian and younger metasedimentary rocks
(KhainandKornousky1997;Rollandetal.2009a,2009b).Thiscontinentalfragmentisa
likelycounterpartoftheSouthArmenianBlocktothenorthwest(Figure1).
International Geology Review 541
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EasternTauride and South Armenianblocks
The Eastern Tauride block, part of the Tauride microcontinent occupying much of
southernTurkey,isrepresentedbytheUpperTriassic–CretaceousMunzurplatforminthe
region(Figures2and3;O¨zgu¨landTurs¸ucu1984).TheTauridemicrocontinentconsistsof
late Proterozoic–Palaeozoic and Mesozoic carbonate, siliciclastic, and volcanic rocks
(O¨zgu¨l1976;Demirtas¸lietal.1984)andrepresentsaribboncontinentriftedofffromthe
northwestern edge of Gondwana (Robertson and Dixon 1984; Sengo¨r et al. 1984; Dilek
andMoores1990;Garfunkel1998).ThePalaeozoic–Jurassictectonostratigraphicunitsin
the Tauride microcontinent are tightly folded and imbricated along major thrust faults.
SouthwestoftheMunzurplatform,theEasternTaurideblockincludesLowerCretaceous
carbonates,overlainbyMaastrichtian–lowerEocenepelagicandhemipelagiclimestones
(Akdere Formation; Robertson et al. 2006). These units are unconformably overlain by
middleEoceneconglomerate,sandstone,andshalewithnomajortectonicbreak(Perinc¸ek
and Kozlu 1984), indicating that sedimentation was nearly continuous throughout the
Mesozoic andearly Palaeogene.
10 The Munzur platform carbonates are tectonically overlain by the Ovacik me´lange
0
2 (Figure 4), consisting of blocks of serpentinites, metamorphic rocks, and pelagic
y
ar limestonesinafine-grained,phylliticmatrix(O¨zgu¨landTursucu1984).BoththeOvacik
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eb me´lange and Munzur carbonates are thrust to the south over the Keban–Malatya
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5 metamorphicrocks(Figure4)thatconsistofPermiantoCretaceousmetacarbonaterocks,
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9 micaschist,phyllite,meta-clasticrocks,andmeta-chert(Michardetal.1984;Perinc¸ekand
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17 Kozlu1984).TheKeban–Malatyametamorphicunitslikelyrepresentthemetamorphosed

t: (greenschistfacies)passivemarginsequenceofthenorthernedgeoftheB–Pcontinental
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] block,facingaNeotethyanseawaytothenorth(Robertsonetal.2006;DilekandSandvol
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ir 2009).
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il The South Armenian Block constitutes the northeastern extension of the Tauride
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, microcontinent. It includes a Proterozoic crystalline basement, overlain by Palaeozoic–
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il Mesozoicsedimentarysequences(Rolland etal.2009a;Sossonetal.2009),reminiscent
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[ of the Eastern Tauride block. It was accreted to the Eurasian margin in the latest
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B Cretaceous–early Palaeogene as the marginal basin south of the Eurasian continental

d
de margincollapsed andclosed(Rolland et al.2009a).
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B–P massif and S–S zone
TheB–PmassiftothesouthisanapproximatelyE–W-trendingcontinentalblock(Figures
2and4)thatwasriftedfromArabiainthePermo-Triassic.Itisboundedbyophioliticthrust
sheets,me´langes,andUpperCretaceousandyoungervolcanicandvolcaniclasticrocks.The
Pu¨tu¨rge massif is composed of pre-Triassic gneisses and micaschists, and granitoids
(Michard et al. 1984; Aktas¸ and Robertson 1990). The Bitlis massif consists of a
Precambrian crystalline basement, metamorphosed Palaeozoic–Triassic carbonate rocks
(Go¨ncu¨ogluandTurhan1984;HelvaciandGriffin1984),andPalaeozoictolateMesozoic
R
Figure3. ModerntopographyoftheArabia–EurasiacollisionzoneandtheTurkish–Iranianhigh
plateau, bounded to the north by the Eastern Pontide arc (Turkey), Greater Caucasus Mountains
(Russia),andElborzMountains(Iran).Majoractivefaults,regionaltectonicentities,stratovolcanoes
(marked in red) and lakes are shown. White arrows show relative plate motions (direction and
velocityinmm/year)withrespecttofixedEurasiabasedontheGPSdataofMcCluskyetal.(2000).
International Geology Review 543
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, Figure 4. Simplified geological map of Eastern Anatolia and the Arabian foreland, showing the
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le distribution of major tectonic units in the region and the post-collisional volcanic rocks in the
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[D Turkishhighplateau.MunzurPlatformconstitutestheeasternextensionoftheplatformcarbonates

: andbasementrocksoftheEasternTaurideribbon-continent.B–Pmassifisariftedofffragmentof
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B theArabianplate,analogoustotheEasternTaurideblock.TheTurkishhighplateauiscoveredby
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de Miocene–Quaternaryvolcanicrocks;itsbasementiscomposedofTethyanophiolitesandophiolitic
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lo me´langes, flysch and molasses deposits, and platform carbonates of the Tauride block. Kac¸kar
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w batholith and the Jurassic–Upper Cretaceous sandstone, volcanic tuff, and limestone in northern
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D TurkeyconstitutetheEasternPontideArc.EAF,EastAnatolianfault;EAFZ,EastAnatolianfault
zone;EKP,Erzurum–Karsplateau;IAESZ,Izmir–Ankara–Erzincansuturezone;KOTJ,Karliova
triplejunction;NAFZ,NorthAnatolianfaultzone;NEAF,NortheastAnatolianfault.
granitoids. Oberha¨nsli et al. (2008) reported a regionally distributed high-pressure/low-
temperature overprint in its metamorphic evolution. The entire Bitlis massif displays a
doublyplunging,multiplyfoldedanticlinoriumwithoverturnedlimbsbothtothenorthand
south(DilekandMoores1990).Therelativelyyoungestthrustfaultsaresouthvergentand
synthetictotheBitlissuture.BoththeBitlisandPu¨tu¨rgemassifsandtheoverlyingvolcanic
andophioliticrocksarestructurallyunderlaininthesouthbyanUpperCretaceous–early
Tertiaryme´lange,whichisunderthrusttothesouthbytheforelandsedimentarysequences
oftheArabianplate(Figure4).
TheeastwardextensionoftheB–PcontinentalblockisrepresentedbytheS–Szone,
whichextendsfor,1500kmalongstrikefromnorthwest(Sanandaj)tosoutheast(Sirjan)
inwesternIran(Figures2and3;Emamietal.1993;MohajjelandFergusson2000).Itis
,150–200kmwideandconsistsmainlyoflateProterozoic–Mesozoicmeta-carbonates,
544 Y. Dileket al.
schist, gneiss, and amphibolite that are intruded by deformed to undeformed granitoid
plutons (Barberian and King 1981; Mohajjel and Fergusson 2000; Moritz et al. 2006;
Mazhari et al. 2009). Metamorphosed Triassic–Lower Jurassic volcano–sedimentary
sequenceswithintheS–Szoneareinterpretedtorepresentrift-driftunitsassociatedwith
the early-stage evolutionof the Southern Neotethys (Alavi and Mahdavi1994; Mohajjel
etal.2003).MiddleJurassictoLateCretaceous,medium-tohigh-pressuremetamorphism
anddeformationrecordedintheS–SrockswererelatedtothesubductionoftheSouthern
Neotethyan seafloor northeastwards beneath this continental block (Barberian and King
1981; Moritz et al. 2006). The general structural fabric is defined by NW-trending and
SW-overturned folds, SW-vergent thrust faults, and NW-trending reverse faults that
collectivelyresultedincrustalthickeningintheS–Szone.Thiscontractionalfabricwas
overprintedbyregional-scale,right-lateraltranspressionaldeformationasevidencedbya
pervasive sub-horizontal stretching lineation and dextral shearing (Mohajjel and
Fergusson 2000). Major magmatic episodes in the tectonic evolution of the S–S zone
are represented by widespread Late Jurassic–Cretaceous, calc-alkaline plutons intruded
0 into the crystalline basement, and by Eocene shoshonitic granitoids crosscutting all its
1
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y
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br IranianVolcanic Belt)tothe NE (Figure 2).
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: The Jurassic(?)–Cretaceous ophiolites underlying the molasse deposits and the Tertiary
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] volcaniccoverintheTurkish–IranianHighPlateauandintheLesserCaucasusrepresent
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ri theremnantsofaMesozoicTethyanoceanandarecommonlydisplacedsouthwardsonto
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l the marginsofthe Eastern Tauride platform (Munzur platform),South ArmenianBlock,
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, B–P massif, and S–S Zone (Figures 2 and 4; Dilek and Moores 1990; Ghasemi and
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le Talbot 2006; Mazhari et al. 2009; Rolland et al. 2009a). The ophiolites resting
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[ tectonically on the Eastern Tauride and South Armenian Blocks were derived from the

:
By IAESZ (Figures 2 and 4) between the Eastern Pontide block and the Tauride

ed microcontinent.ThecoevalophiolitesrestingtectonicallyontheB–PmassifandtheS–S
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oa Zone farther south (Figures 2 and 4) were derived, on the other hand, from a separate
l
n
w NeotethyanbasinthathadevolvedalongthenorthernperipheryofArabiathroughoutthe
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Mesozoic(RobertsonandDixon1984;Sengo¨retal.1984;DilekandMoores1990;Dilek
et al. 1999a).
EasternAnatolianandUrumieh–Dohktarmagmaticarcs
Aregional,lateMesozoictoEocenemagmaticarcsystemextendsalongthenorthernedge
oftheB–PandS–ScontinentalblocksimmediatelynorthoftheArabianplate(Figure2).
The Late Cretaceous Neotethyan ophiolites and the B–P and Keban–Malatya
metamorphic units in southeastern Turkey are crosscut by kilometre-scale granitoid
plutons(Perinc¸ekandKozlu1984;YazganandChessex1991;Parlak2006),whichhave
I-type,calc-alkalinegeochemicalaffinities(Parlak2006).TheBaskilmagmaticsequence
(Figure4;intheElazig–PalunappeofYazgan1984)northoftheB–Pmassifconsistsof
calc-alkaline intrusive and extrusive rocks, with overlying Campanian–Maastrichtian
volcaniclastic and flysch deposits (Michard et al. 1984; Yazgan 1984). The Santonian–
Campanian (85–77Ma) granodiorite, tonalite, quartz monzonite, monzodiorite, diorite,
and gabbro rocks of the Baskil igneous sequence represent a magmatic arc constructed