Subduction, ophiolite genesis and collision history of Tethys adjacent to the Eurasian continental margin: new evidence from the Eastern Pontides, Turkey

Figures & data

Figure 1. Outline tectonic map of the circum-Black Sea region of NE Turkey. This paper focuses on the eastward extension of the İzmir–Ankara–Erzincan suture zone through the Eastern Pontides, and comparisons especially with the Central Pontides and the Lesser Caucasus. Modified from Ustaömer and Robertson (2010). PCF, Peceneaga Camena Fault; CTF, Caucasian Thrust Front; S, Svenata uplift; RD, Rioni Depression; DZ, Dzirula salient; KH, Khrami salient; LS, Lochi salient; CUZ, Chorchana–Utslevi Zone.

Figure 2. Simplified N–S cross-sections of the İzmir–Ankara–Erzincan suture zone in the Eastern Pontides. (a) West of the area; (b) East of the area (see Figure 1). Based on the 1:500,000 Geological Map of Turkey (MTA, 2002), with modifications resulting from this work. NAF North Anatolian Transform Fault.

Figure 3. Outline tectonic map of the İzmir–Ankara–Erzincan suture zone and its eastward extension (Erzurum–Kars suture zone), cover units, together with the Eurasian continental margin and the Tauride continental margin to the south. Areas studied here are shown by the boxes and lines of section. Simplified from the 1:500,000 Geological Map of Turkey (MTA, 2002).

Figure 4. Summary tectono-stratigraphy based on this work. A Cretaceous subduction-accretion complex is overthrust by Lower Jurassic ophiolites. These are intercalated with Jurassic–Cretaceous sedimentary rocks derived from the Eurasian continental margin. The ophiolite is overthrust by contrasting sedimentary and volcanogenic successions in the east vs. the west of the region. Several units of metamorphic rocks (locally dated as Jurassic) are excluded because they occur in different structural positions in different areas.

Figure 5. Outline tectonic map of the Şahvelet area, Erzurum Region. An upper, folded thrust sheet of ophiolitic rocks, mostly serpentinised peridotite, is structurally underlain by the volcanic-sedimentary and ophiolitic melange. In different areas, the melange and/or the ophiolite are overthrust by Upper Cretaceous deep-water pelagic and volcaniclastic sediments derived from the Eurasian continental margin (see Figure 3 for location; compiled from Parlak, Çolakoğlu, et al., 2013; Tarhan, l988; Yılmaz, Terlemez, & Uysal, 1986, 1988a, 1988c, l989; Yilmaz et al., 1988b; Yilmaz & Uysal, 1988 and this study).

Figure 6. Outline tectonic map of the area north of Horasan, Kars Region. Two contrasting types of melange are exposed. First, volcanic-sedimentary melange, with exotic blocks (e.g. limestone; volcanics), set in a sedimentary matrix and, secondly, ophiolitic melange made up of dismembered ophiolitic rocks. There are also dismembered sequences of Upper Cretaceous mixed carbonate-volcaniclastic sediments that are interpreted as part of the emplaced Eurasian continental margin (see Figure 3 for location; compiled from Konak and Sümengen (2009) and this study).

Figure 7. Outline tectonic map of the Erzincan area (Erzincan and Gümüşhane regions). An ophiolite, complete other than for extrusive rocks, is thrust over volcanic-sedimentary and ophiolitic melange. Both units are unconformably covered by Eocene sediments and, in some areas, by Miocene and Plio–Quaternary sediments. Outcrops of greenschist facies metamelange occur in the south and northeast. The southern part of the area is cut by the North Anatolian Transform Fault, which is this area is associated with formation of the neotectonic Erzincan pull-apart basin (see Figure 3 for location; compiled from Aktimur et al., 1995; Parlak, Çolakoğlu, et al., 2013; Tarhan, l988, 2007a, 2007b and this study).

Figure 8. Cross-sections and measured logs of local sequences within blocks and dismembered thrust sheets that form part of the volcanic-sedimentary and ophiolitic melange, (a) volcanogenic lithologies, depositionally overlain by radiolarian sediments, passing upwards into volcanogenic shale; (b) volcanogenic lithologies depositionally overlain by redeposited limestones and then by radiolarian and hydrothermal sediments, passing upwards into shale; (a–b) East side of Aras Nehri (river) near road bridge; Şahvelet area; (c) volcanogenic lithologies depositionally overlain by chert, passing upwards into limestone; NE of Aziziye, Şahvelet area, Erzurum Region). Samples that were dated using radiolarians (numbers with arrows) are also shown in Figure 9(a) and (b), together with data from other areas. See text for discussion.

Figure 9. Occurrences of dated radiolarites associated with blocks and dismembered thrust sheets within the volcanic-sedimentary and ophiolitic melange. (a) Upper Tithonian radiolarites spatially associated with basaltic pillow lava (although separated by a thin thrust sheet of sheared serpentinite), E of Erzincan; (b) Pliensbachian radiolarites stratigraphically interbedded with pillow lavas, E of Erzincan; (c) Lower Turonian radiolarites overlying pillow basalt, near Otlukbeli, SW of Bayburt; (d) Valanginian? radiolarites overlying pillow basalt, near Aziziye, Erzurum Region; (e) Late Hauterivian–Early Barremian radiolarites overlying pelagic limestones that, in turn, cover massive basalt, Şahvelet area; (f) Pliensbachian radiolarites stratigraphically interbedded with massive basalt; Şahvelet area. Bedding is recorded as angles of dip and strike. See text for explanation.

Figure 10(A). SEM images of age-diagnostic Radiolarian from blocks associated with basaltic rocks in the volcanic-sedimentary and ophiolitic melange. Sample E2-11-50 (near Azize; Şahvelet area). 1 – Acanthocircus sp. ×100; 2 – Dicerosaturnalis amissus (Squinabol), 3 – Acaeniotyle cf. diaphorogona Foreman, 4 – Acaeniotyle cf. diaphorogona Foreman, ×100; 5 – Angulobracchia cf. biordinalis Ozvoldova, ×150; 6 – Angulobracchia cf. portmanni Baumgartner, ×75; 7 Aurisaturnalis variabilis (Squinabol), 250; 8 – Praeconosphaera sphaeroconus (Rüst), ×150; 9, 10 – Archaeodictyomitra cf. praegutta Dumitrica, ×100; 11 – Pseudodictyomitra cf. carpatica (Lozyniak), ×150; 12 – Sethocapsa? sp., ×200; 13 – Spongacapsula obesa Jud, ×200; 14 – Thanarla pulchra (Squinabol), ×200; 15 – Archaeodictyomitra sp., ×125; 16 – Nassellaria gen. et sp. indet., ×125. Sample E2-11-86 (Aras Nehri gorge; Şahvelet area) 17 – Alievium regulare (Wu & Li), ×125; 18 – Sethocapsa trachyostraca Foreman, ×125; 19 Sethocapsa uterculus Parona, ×250; 20 – Syringocapsa limatum Foreman, ×100; 21 – Svinitzium pseudopuga Dumitrica, ×150; 22 – Suna echiodes (Foreman), ×150; 23 – Pseudoxitus laguncula Dumitrica, ×150; 24 – Pseudodictyomitra nodocostata Dumitrica, ×150; 25 – Pseudoaulophacus (?) florealis Jud, ×125; 26 – Syringocapsa spinosa (Squinabol), ×150; 27 – Parvicingula usotanensis Tumanda, ×150; 28 – Tethysetta boessi gr. (Parona), ×125; 29 – Pantanellium sp., ×100; 30 – Mirifusus dianae (Karrer), ×85; 31 – Mictyoditra curvata Dumitrica, ×150; 32 – Holocryptocapsa hindei (Tan), ×130; 33 – Hemicryptocapsa capita Tan, ×150; 34 – Dicerosaturnalis trizonalis (Rüst), ×100; 35 – Crucella bossoensis Jud, ×125; 36 – Cecrops septemporatus (Parona), ×150; 37 – Pseudoeucyrtis sp., ×150.

Figure 10(B). SEM images of age-diagnostic Radiolarian from blocks associated with basaltic rocks in the volcanic-sedimentary and ophiolitic melange. Sample E2-11-87 (Aras Nehri gorge; Şahvelet area): 1 – Archaeodictyomitra apiarium (Rüst), ×150; Pantanellium squinaboli (Tan), ×200; 3 – Pantanellium sp., ×200; 4 – Sethocapsa trachyostraca Foreman, ×100; 5 – Svinitzium pseudopuga Dumitrica, ×125; 6 – Xitus sp., ×125. Sample E2-11-90 (Aras Nehri gorge; Şahvelet area): 7 – Alievium regulare (Wu & Li), ×125; 8 – Archaeotritrabs gracilis Steiger, ×100; 9 – Becus helenae (Schaaf), ×125; 10 – Napora sp., ×200; 11 – Orbiculiforma satoi Tumanda, ×100; 12–14 – Pantanellium masirahense gr. Dumitrica, ×125; 15 – Tethysetta usotanensis (Tumanda), ×150; 16 – Phaseliforma cf. micropora (Tan), ×100; 17 – Praexitus alievi (Foreman), ×100; 18 – Tetracapsa sp., ×200; 19 – Thanarla conica (Aliev), ×200; 20 – Veghicyclia ? sp.; 21 – Xitus robustus Wu, ×150. Sample E2-11-94 (Aras Nehri gorge; Şahvelet area): 22 – Thanarla cf. gutta Jud, ×100; 23 – Archaeodictyomitra sp., ×125; Sample E2-11-106 (Şahvelet Dağ) (24 – Gigi fustis De Wever, ×150; 25–26 – Lantus intermedius gr. Carter, ×150. Sample E2-11-177: 27 – Canoptum cf. anulatum Pessagno & Poison, ×125; 28 – Canoptum cf. artus Yeh, ×100; 29 – Droltus sp., ×200. Sample E2-11-176 (E of Erzincan): 30 – Pantanellium aff. riedeli Pessagno, ×125; 31 – Saitoum cf. labeosum Dumitrica & Zügel, ×150; 32 – Bernoullius cf. delnortensis Pessagno, Blome & Hull, ×150; 33 – Pseudodictyomitra primitiva Matsuoka & Yao, ×150; 34 – Perispyridium ordinarium (Pessagno), ×150; 35 – Protunuma costata (Heitzer), ×150; 36 – Spongocapsula sp., ×100; 37 – Emiluvia chica Foreman, ×150; 38 – Napora deweveri Baumgartner, ×150. Sample E2-11-171 (Otlukbeli area): 39 – Pseudodictyomitra pseudomacrocephala (Squinabol), ×100; 40 – Crucella cachensis Pessagno, ×125; 41 – Hemicryptocapsa praepolyhedra Dumitrica, ×150; 42 – Archaeodictyomitra sp.1, ×125; 43 – Alievium superbum (Squinabol), ×150; 44 – Archaeodictyomitra sp.2, ×175; 45 – Patellula ecliptica O’Dogherty, ×125.

Figure 11. Field photographs. (a) Volcanic-sedimentary melange showing blocks, mainly limestone, in a matrix of shale and sandstone; the melange is traversed by sheared serpentinite (darker grey; middle distance); NW of Aziziye) (see Figure 5); (b) Debris-flow conglomerate within the matrix of the volcanic-sedimentary melange. Well-rounded clasts of pelagic limestone (pale) and basalt (dark) in a sandy and pebbly matrix; road paralleling Aras Nehri (river) (see Figure 5); (c) Debris-flow conglomerate with well-rounded clasts including gabbro, basalt, limestone and chert, set in a coarse sandy matrix; volcanic-sedimentary melange; near junction of main road to Çatalelma; Kırdağ area (40°28′ 12.2″N, 42°20′22.5″E) (see Figure 18); (d) Thrust sheet of sheared serpentinite (foreground, left) within dismembered sequence of Upper Cretaceous volcaniclastic sandstones and shales, above and below (Eurasian margin derived; 4 km W of Akören köy, Horasan area (see Figure 6); (e) Ophiolite-derived debris flow, with clasts of gabbro, basalt and serpentinite in a coarse ophiolite-derived clastic matrix; ~3.5 km NW of Dönertaş, Horasan area (40°14′36.5″N, 42°06′54.6″E). (see Figure 6); (f) Metadebris flow unit within the matrix of metamorphic melange (Zümrüt Metamorphics). Stretched clasts of metabasalt and metagabbro are set in a schistose, micaceous matrix (40°33′13.1″N, 42°12′31.3″E) (see Figure 18); (g) Thrust sheet of Upper Cretaceous–Palaeocene limestone related to the Eurasian margin succession, thrust over Jurassic ophiolitic gabbro; Talas Dağı area; see Figure 7; (h) Isoclinal fold (S-verging), cored with dark grey chert, near the top of the carbonate platform succession; Eurasian margin succession, dated as Late Cretaceous during this work; 5 km NW of Otlukbeli; see Figure 31 (40°01′38.8″N, 39°55′47.4″E); (i) Southward-younging succession of Upper Cretaceous volcanogenic sandstone turbidites, interbedded with mudstone; see Figure 25(b); near Başaklıköy; S of Karadağ (near 40°26′41.6″N, 41°50′22.8″E); (j) Debris-flow conglomerate with well-rounded clasts, including basaltic andesite and pelagic limestone set in a coarse sandy matrix; part of the Late Palaeocene?–Eocene succession that structurally underlies the Kırdağ ophiolite (SW of Bahçelikışla; 40°34′59.3″N, 42°08′49.2″E) (see Figures 18 and 32); (k) Unconformity between the Late Palaeocene–Early Eocene succession of marine clastic gravity-flow deposits and overlying Late Middle Jurassic (Bartonian) non-marine clastic sedimentary rocks (near Yukarı Kumlu; near 40°37′26.9″N, 36′07′48.4″E) (see Figures 18 and 32); (l) Open-folded marine Palaeocene sediments, unconformably overlain by non-marine red-beds, evaporites and caliche, marking the base of the Middle Eocene marine succession; view north-westwards from near Bozdoğan; Olur area (see Figure 33); (m) Volcaniclastic turbidites; Middle Eocene; NW of Bozdoğan, Olur area (see Figure 33 39°59′03.5″N, 42°10′32.1″E); (n) Eocene marine sandstones and shales (turbidites) overlying the northern part of the suture zone. N of Erzincan (see Figure 7) (39°54′53.5″N, 39°36′38.8″E); (o) Strongly folded Miocene shallow-marine sediments; 10 km WSW of Refahiye (39°54′53.5″N, 39°36′38.8″E); see Figure 23).

Figure 12. Setting of Upper Cretaceous pelagic carbonates, sandstone-mudstone turbidites and polymict debris-flow deposits within the volcanic-sedimentary melange. (a) Measured log; (b) Outcrop profile; (c) Tectonic model, showing a small basin that was later imbricated with the volcanic-sedimentary melange. These gravity deposits are interpreted as the remains of one of a number of small, perched basin within the Cretaceous accretionary wedge. These sediments provide evidence of a Late Cretaceous age of accretionary melange formation.

Figure 13. Rock classification diagram utilising relatively immobile elements (template according to Pearce, 1996). All of the volcanic rocks analysed plot in the basalt and alkali basalt fields.

Figure 14. N-MORB-normalised rare earth element plots showing the different groups of basaltic rocks identified. Normalising values from Sun and McDonough (l989). See text for explanation.

Figure 15. Chondrite-normalised rare earth element plots showing the different groups of basaltic rocks identified. Normalising values from Sun and McDonough (l989). See text for explanation.

Figure 16. Cross-section showing 1 – Slices of internally coherent ophiolitic rocks (lefthand side); 2 – Volcanic-sedimentary melange, including dismembered blocks of ophiolitic rocks; 3 – Dismembered thrust sheet of Upper Cretaceous-Palaeocene? Carbonate rocks (e.g. Talas Dağı) which is correlated with the Eurasian margin succession; 4 – Unconformably overlying Oligo–Miocene succession. See Figure 7 for location.

Figure 17. Outline tectonic map of the Karadağ ophiolite and related units (see Figure 3). The Karadağ ophiolite includes well-preserved upper crustal rocks (layered and isotropic gabbros and basaltic extrusives). Sheeted dykes are locally exposed as small slices associated with ophiolitic gabbro (in the central south of the outcrop). The ophiolitic rocks are structurally overlain by Jurassic–Cretaceous sedimentary and volcanic rocks related to the Eurasian continental margin (compiled from Konak et al., 2001; Konak & Hakyemez, 2008b; Parlak, Çolakoğlu, et al., 2013 and this study). For section A–B see Figure 25(b).

Figure 18. Outline tectonic map of the Kırdağ area. A large thrust sheet of dismembered serpentinised ultramafic rock is structurally underlain by a tectonic slice complex, which is made up of dismembered upper crustal ophiolitic rocks, intersliced with volcanic-sedimentary and ophiolitic melange and Eurasian margin-derived sediments. The ophiolitic gabbro is cut by a tonalite intrusion, radiometrically dated as Early Jurassic. Late Cretaceous pelagic carbonates and Late Palaeocene?–Early Eocene terrigenous gravity flows structurally underlie the peridotite nappe. The area also hosts a metamorphic melange (undated) with blocks of HP-LT lithologies and an underlying slice of metaterrigenous sandstone (also undated) (see Figure 3; compiled from Konak & Hakyemez, 2008a; Konak & Sümengen (2009); Parlak, Çolakoğlu, et al., 2013 and this study).

Figure 19. Outline tectonic map and cross-section of the area SW of Erzincan. A thrust sheet of plutonic rocks belonging to the Refahiye Ophiolite is structurally underlain by an unusual unit that is made up of metamorphic rocks (e.g. marble and schist), cut by swarms of diabase dykes. Ophiolitic gabbro and the volcanic-sedimentary melange are thrust over Late Cretaceous–Eocene arc-related volcanic rocks (Karadağ Massif) further south (see Figure 3; compiled from Tarhan (2008), Rice et al. (2006) and this study).

Figure 20. Selected cathodoluminesence (CL) images of dated zircon crystals. The textures are typical of igneous zircons. Homogenous areas of zircon crystals were selected for analysis, while rims were avoided. Scale bars are 50 μm long unless otherwise indicated. See text for explanation.

Figure 21. Key structural relationships in the Erzincan area; (a) Serpentinised peridotite cut by isolated sheared diabase dykes and later thrust over serpentinite melange; NW of Erzincan; (b) Serpentinised peridotite cut by isolated sheared diabase dykes; this was then intercalated with ophiolitic gabbro and thrust over the volcanic-sedimentary and ophiolitic melange; N of Erzincan; (c) Volcanic-sedimentary and ophiolitic melange covered unconformably by Eocene basinal sediments and, in turn, by Plio–Quaternary clastic sediments; NW of Erzincan; (d) Volcanic-sedimentary and ophiolitic melange unconformably overlain by Eocene marine sediments, including channellised facies near the base. NE of Erzincan, see Figure 7 for locations of sections.

Figure 22. Isochron plots of age data for the dismembered and ordered ophiolites. EZ-11-62: Gabbro cumulates from a gabbroic slice within ophiolitic melange (i.e. dismembered ophiolite) in the Horasan area; EZ-11-79 and 80: Two samples from a tonalite body (Karataştepe Granitoid) that cuts isotropic ophiolitic gabbro (i.e. dismembered ophiolite) in the Kırdağ area; EZ-11-24: Gabbro cumulate from the Karadağ Ophiolite (i.e. ordered ophiolite); EZ-11-59: Gabbro cumulate from the Kop Dağ Ophiolite (ordered ophiolite), W of Aşkale); EZ-11-179: Plagiogranite cutting the sheeted dykes of the Refahiye Ophiolite, W of Erzincan (included with the ordered ophiolite although it comes from a thrust sheet beneath the main ophiolite body). The results show that all of the ophiolitic rocks and the crosscutting tonalite crystallised during Early Jurassic time. See text for further explanation.

Figure 23. Outline tectonic map showing the relationship of the Refahiye ophiolite to adjacent units (Figure 3) (Compiled from MTA, 2002 and this study.). Serpentinised peridotite, cut by diabase dykes, is overthrust by a large sheet of Jurassic metamelange, which includes a large marble unit. The area is transected by the North Anatolian Transform Fault in the northeast. The map highlights the westward extension of the Refahiye Ophiolite and the presence of metamorphic melange (locally dated as Jurassic), intersliced with ophiolitic rocks (see Topuz et al., 2013).

Figure 24. Cross-section of the Kırdağ serpentinised peridotite nappe in relation to underlying units. In the north, a dismembered ophiolite is thrust over Upper Cretaceous pelagic carbonates and Palaeocene?–Early Eocene terrigenous gravity flows (see Figure 25(b)). To the south, the ophiolite is underlain by two contrasting metamorphic units, first, a melange with blocks of HP-LT metamorphic rocks and secondly, a slice of sandstone turbidites. The melange with HP-LT metamorphic rocks includes lenses of metaclastic sediments and sheared ultramafic rocks (see Figure 3; compiled from Konak & Hakyemez, 2008a; Konak & Sümengen, 2009; Parlak, Çolakoğlu, 2013 and this study).

Figure 25. Cross-sections of Eurasian margin-derived sedimentary rocks that were emplaced over the oceanic rocks of the suture zone. (a) Volcaniclastic sandstones and shales passing upwards into a thick, folded sequence of Upper Cretaceous pelagic carbonates. Way-up and structural evidence suggest that this sequence forms the upper limb of a large-scale ~N-facing recumbent syncline, consistent with ~N-directed thrusting. In the NW, the sequence is thrust over red conglomerates (Oligocene?), with derived clasts of Late Cretaceous limestone. The red conglomerates are, in turn, thrust over the volcanic-sedimentary and ophiolitic melange. Şahvalet area, near Aziziye; see Figure 5); (b) Upper Cretaceous volcaniclastic turbidites passing upwards into Upper Cretaceous redeposited carbonates (above a minor shear zone), which are thrust over basaltic extrusives of the Karadağ ophiolite; N margin of Karadağ massif; see Figure 17.

Figure 26. Regional reference successions compared to successions measured during this work. (a) Distal (southerly) Pontide continental margin; (b) Proximal (northerly) Pontide continental margin (a–b reference successions; see e.g. Okay & Şahintürk, l997a); (c–e) Slices of Eurasian-derived sediments from within the Pontide suture zone. Accretionary melange was emplaced over the distal (southerly) margin of Eurasia during the Late Cretaceous, while sedimentation continued further north into Early Eocene time.

Figure 27. Photomicrographs of Upper Cretaceous–Eocene sandstones from the suture zone and the adjacent Eurasian continental margin. (a) Redeposited carbonate (packstone) with neritic bioclast fragments (e.g. bivalves, calcareous algae, echinoderm plates) in the highest levels of the Eurasian margin succession (half-polarised light); 5 km NW of Otlukbeli (SW of Bayburt); see Figure 31 (40°01′38.8″N, 39°55′47.4″E); (b) Sublitharenite (plane-polarised light); largely quartz, altered basalt and basaltic glass, plus clinopyroxene, with a calcite spar cement (Bardızçayı Formation, near Doşkaya, Kırdağ area; see Figure 29; 40°29′26.6″N, 42°13′44.8″E); (c) Subarkose (crossed nicols). Feldspar (zoned plagioclase) in a matrix of volcaniclastic siltstone, including rare clinopyroxene and hornblende; Upper Cretaceous (Bardızçayı Formation); main road south of Zümrüt (to Çatalelma), Kırdağ area; see Figure 18; 40°31′21.7″N, 42°14′49.0″E); (d) Litharenite (plane-polarised light). Upper Cretaceous volcanogenic sandstone (plane-polarised light); N of Karadağ; abundant basaltic and feldspar (plagioclase grains; near Başaklı köy; see Figure 25(b); 40°27′24.8″N, 41°47′46.0″E); (e) Litharenite (plane-polarised light). Upper Cretaceous volcanogenic sandstone, rich in basalt and plagioclase, together with some clinopyroxene and hornblende; 4 km W of Akören köy, Horasan area (see Figure 5, 40°15′34.5″N, 42°12′39.1″E); (f) Litharenite (crossed nicols). Upper Cretaceous volcanogenic sandstone, compositionally similar to e; see Figure 5 for location; NW of Aziziye; near 39°48′55.6″N, 41°22′29.3″E); (g) Litharenite (serpentinite-rich, coarse, poorly sorted sandstone (half crossed nicols); c. 3.5 km NW of Dönertaş, Horasan area (see Figure 6); 40°14′36.5″N, 42°06′54.6″E). (h) As g, serpentinite grains in calcite spar cement (crossed nicols); (i) Subarkose (crossed nicols); common grains of feldspar, altered basalt and quartz with a calcite spar cement; near base of Eocene sequence, 3000 m of Ağılözü, NW of Erzincan (39°52′52.1″N, 39°19′40.5″E); (j) Litharenite (half-polarised light); basaltic grains with plagioclase microphenocrysts in matrix of devitrified glass; calcite spar cement; Middle Eocene; NW of Bozdoğan; Olur area (see Figure 33, 39°53′09.6″N, 39°27′23.1″E); (k) Litharenite (half-polarised light); including silicic volcanic grains; Upper Palaeocene?–Eocene succession that structurally underlies the Kırdağ ophiolite (see Figure 25(b); SW of Başaklı köy; 40°34′59.3″N, 42°08′49.2″E); (l) Litharenite (tuff); volcanic glass (tephra) within relatively deep-marine foraminiferal sediments (half-polarised light); Middle Eocene; NW of Bozdoğan, Olur area (see Figure 33); 40°53′06.1″N, 42°06′02.7″E). Key to grains: Ba, Basalt; Ca, Calcite; C, Chlorite (altered basic volcanic); F, Feldspar; Fo, Planktic foraminifer; Py, Clinopyroxene; Q, Quartz; R, Rhyodacite; S, Serpentinite; T, Tephra (volcanic glass).

Table 1. Summary of the calcareous microfossils identified, as referred to in the text, together with geographical coordinates.

Sample	Microfossils	Age
Horasan area		Albian to Maastrichtian
65	Hedbergellidae
68	Globotruncana dupeublei, Globotruncanita pettersi, Planoglobulina carseyae, Racemiguembelina fructicosa, Rugoglobigerina rugosa	Late Maastrichtian
69	Pseudocyclammina lituus, Charentia sp., Spiroloculina sp., Salpingoporella annulata, Actinoporella podolica	Berriasian–Barremian
34A	Globotruncanella petaloidea, Globotruncanita sp., Rugoglobigerina milamensis, Heterohelicidae	Maastrichtian
35A	Abatomphalus mayaroensis, Rugoglobigerina pennyi, Archaeoglobigerina bosquensis, Globotruncana arca, Heterohelicidae	Late Maastrichtian
43A	Archaeoglobigerina sp., Globotruncana bulloides, Globotruncana arca, G. linneiana, G. falsostuarti, Globotruncanita sp., Pseudotextularia sp.	Late Campanian–Maastrichtian
71	Trocholina sp., Miliolidae, Textulariidae	Jurassic–Cretaceous
Kırdağ area
15A	Pseudosiderolites vidali, Smoutina cruysi, Corallin alga, bryozoa	Maastrichtian
17	Spiroloculina sp., Haplophragmoides sp., Praechrysalidina sp., Miliolidae	Early Cretaceous
19	Everticyclammina sp., Bolivinopsis sp., Miliolidae, Salpingoporella cf. S. muehlbergii	Barremian
76	Mayncina bulgarica, Pseudochoffatella sp., Spiroloculina sp., Permocalculus sp.	Berriasian–Barremian
82	Protopeneroplis sp.	Bathonian to Berriasian
83	Globotruncana linneiana, Archaeoglobigerina cretacea, Globigerinelloides sp., Heterohelix reussi, Radiolaria	Campanian–Maastrichtian
Karadağ area
122	‘Tubiphytes’ morronensis (reworked), sponge spicules, echinoderm debris	Late Jurassic
123	Sponge spicules, echinoderm debris	?
124	Verneuilina sp., Everticyclammina sp., Thaumatoporella sp.	Jurassic-Cretaceous
Şahvelet area (Erzurum)
52	Involutina liassica, Agerina martana	Early Jurassic
53	Agerina martana, Glomospira sp., Nodosariidae, sponge spicule, echinoderm debris, bryozoa,	Early Jurassic
107	Globotruncana linneiana, Globotruncanella petaloidea, Radiolaria	Maastrichtian
109	Contusotruncana contusa, Globotruncana arca, Globotruncana linneiana, Radiolaria	Maastrichtian
111	Globotruncana orientalis, Contusotruncana fornicata, C. walfischensis, Rugoglobigerina rugosa	Maastrichtian
112	Archaeoglobigerina cretacea, Globotruncana arca, Globotruncana linneiana, Heterohelicidae	Campanian–Maastrichtian
113	Globotruncana arca, G. linneiana, Heterohelicidae	Campanian–Maastrichtian
50A	Calcisphaerula innominata, Pithonella ovalis, Globigerinelloides sp., Hedbergellidae, Heterohelicidae	Late Cretaceous
57	Archaeoglobigerina sp., Globotruncana linneiana, Heterohelicidae, Radiolaria	Campanian–Maastrichtian
58	Globotruncanella petaloidea, Globotruncana linneiana, Radiolaria
116	Pseudosiderolites vidali, Smoutina cruysi, Sirtina orbitoidiformis	Late Maastrichtian
Otlukbeli area (Bayburt Region)
165	Hedbergella monmouthensis	Campanian–Maastrichtian
168	Orbitolinopsis sp., Orbitolina sp. (reworked)	Early Cretaceous or younger
164	Verneuilina sp.	Jurassic-Cretaceous
Erzincan area
193	Protopeneroplis striata, Mohlerina basiliensis,; ‘Tubiphytes’ morronensis	Late Jurassic
194	Protopeneroplis striata, Labyrinthina mirabilis, ‘Tubiphytes’ morronensis	Late Jurassic
182	‘Tubiphytes’ morronensis	Late Jurassic
184	Verneuilina sp., ‘Tubiphytes’ morronensis, Calpionellidae (reworked)	Late Tithonian–early Berriasian
175	Amphistegina lessonii, Operculina complanata, Planorbulina sp., Asterigerina rotula, Amphiroa propria, Jania sp.	Miocene
178	Miolepidogypsina sp., Baculogypsina sp., corallin alga, bryozoa, ostreid	Miocene

Notes: Geographic coordinates of sample locations;

Horasan

65 near Akören köyü; 40°16′28.1″N, 42°10′21.9″E

68 & 69 Akören köyü area; 40°16′46.8″N, 42°09′39.0″E

34A & 35A near Kalandere; 40°05′26.0″N, 42°02′03.9″E

43A near Yatıksırt; 40°07′41.0″N, 42°05′18.9″E

71 Akören köyü area; 40°16′46.8″N, 42°09′38.5″E

Kırdağ

15A near Turnalı road turning; 40°31′43.6″N, 42°15′22.6″E

17 & 19 near Turnalı road turning; 40°31′21.7″N, 42°14′49.0″E

76 same area; 40°29′15.5″N, 42°13′49.2″E

82 & 83 above Çatalelma köyü; 40°28′12.2″N, 42°20′22.5″E

Karadağ

25A & 27A near Başaklı köyü; 40°26′50.7″N, 41°50′37.3″E

28A near Başaklı köyü; 40°27′24.1″N, 41°50′59.1″E

26, 122, 123, 124 & 125 near Başaklı köyü; 40°26′41.6″N, 41°50′22.8″E

125 near Başaklı köyü; 40°28′05.8″N, 41°35′52.2″E

Şahvelet

52 & 53 Aziziye area; 39°49′03.0″N, 41°18′33.2″E

88 Aras Nehri; 39°50′00.9″N, 41°46′23.6″E

107, 109, 111, 112, 113 & 116 Aziziye area; 39°48′55.6″N, 41°22′29.3″E

50A Aziziye area; 39°48′54.0″N, 41°18′01.9″E

57& 58 Aziziye area; 39°48′42.9″N, 41°23′10.0″E

Otlukbeli

164 & 165; 40°01′22.2″N, 39°56′06.8″E

168; 40°01′38.8″N, 39°55′47.4″E

Erzincan

193 & 194 near Yeşilyurt, N of Erzican; 39°56′25.9″N, 39°20′00.5″E

182 NE of Erzincan near Saraycık; 39°46′41.9″N, 40°04′52.7″E

175 main road E of″Erzincan; 39°35′23.6″N, 39°52′42.9″E

178 NE of Erzincan, Kapılıdağ; 39°36′54.1″N, 33 50′49.7″E

Figure 28(A). Micopalaeontological evidence. Mesozoic microfossils (benthic foraminifers, calpionellids and algae) (a) Agerina martana (Farinacci), sample 52; (b) Involutina liassica (Jones), sample 52; (a–b) Şahvalet area; Early Jurassic; (c) Calpionella alpina Lorenz (Ca), Crassicollaria sp. (C), sample 125; (d) ‘Tubiphytes’ morronensis Crescenti, sample 184; (a–d) Karadağ area; Late Tithonian; (e) Labyrinthina mirabilis Weynschenk, sample 194; (f) Protopeneroplis striata Weynschenk, sample 193, Erzincan area, block in melange; Late Jurassic (Late Oxfordian–Early Kimmeridgian). (g) Verneuilina sp., sample 26, Karadağ Massif, Late Tithonian; (h) Salpingoporella cf. S. muehlbergii (Lorenz), sample 19, Kırdağ area; Barremian; (i) Salpingoporella annulata Carozzi, sample 69, Horasan area; Early Cretaceous; (j) Palorbitolina lenticularis (Blumenbach), sample 84, Kırdağ area, late Barremian–early Aptian; (k) Mayncina bulgarica Laug et al., sample 76, Kırdağ area; Early Cretaceous; (l) Actinoporella podolica (Alth), sample 69, Horasan area; Early Cretaceous; (m) Smoutina cruysi Drooger, (n) Sirtina orbitoidiformis Brönnimann & Wirz, (o) Pseudosiderolites vidali (Douville), sample 116, Late Maastrichtian, (m–o), Şahvalet area; near Aziziye; Scale bars: .2 mm.

Table 2. Radiolarian ages inferred from the samples studied.

Species	Samples
	E2-50	E2-86	E2-87	E2-90	E2-94	E2-106	E2-171	E2-176	E2-177
Acaeniotyle diaphorogona Foreman	+				+
Acaeniotyle umbilicata (Rüst)	+
Acanthocircus sp.	+
Alievium regulare (Wu & Li))		+		+
Alievium superbum (Squinabol)							+
Angulobracchia cf. biordinalis Ozvold.	+
Angulobracchia portmanni Baumg.	+
Angulobracchia sp.	+
Archaeodictyomitra apiarium (Rüst)		+	+
Archaeodictyomitra elegans (Tan)		+
Archaeodictyomitra mitra Dumitrica		+
Archaeodictyomitra cf. praegutta Dum.	+
Archaeodictyomitra sp.	+		+				+
Archaeotritrabs gracilis Steiger				+
Aurisaturnalis italicus (Squinabol)			+
Aurisaturnalis variabilis (Squinabol)	+		+
Becus helenae (Schaaf)				+
Bernoullius cf. delnortensis Pess. et al.								+
Canoptum cf. anulatum Pess. & Poisson									+
Canoptum cf. artum Yeh									+
Cecrops septemporatus (Parona)		+	+	+
Crucella cf. bossoensis Jud		+	+
Crucella cachensis Pessagno							+
Dactyliosphaera silviae Squinabol							+
Dicerosaturnalis amissus (Squinabol)	+
Dicerosaturnalis trizonalis (Rüst)		+	+
Droltus sp.									+
Emiluvia chica Foreman								+
Fultacapsa sphaerica (Ozvoldova)								+
Gigi fustis De Wever						+
Halesium sexangulum Pessagno							+
Hemicryptocapsa capita Tan		+	+	+
Hemiocryptocapsa praepolyhedra Du.							+
Holocryptocapsa hindei (Tan)		+				+
Lantus intermedius Carter
Mictyoditra curvata Dumitrica		+
Mirifusus dianae (Karrer)		+
Napora deweveri Baumgartner								+
Napora sp.				+
Orbiculiforma ? kanayamaensis Mizut.								+
Orbiculiforma ? satoi Tumanda				+
Pantanellium masirahense Dumitrica				+
Pantanellium aff, riedeli Pessagno								+
Pantanellium sp.		+	+					+
Pantanellium squinaboli (Tan)			+
Parapodocapsa furcata Steiger								+
Parvicingula boessi gr. (Parona)		+
Parvicingula usotanensis Tumanda		+		+
Parvicingula sp.								+
Patellula ecliptica O’Dogherty							+
Perispyridium ordinarium (Pessagno)								+
Phaseliforma? cf. micropora (Tan)				+
Podobursa triacantha Fischli				+
Podobursa sp.				+
Podocapsa amphitreptera Foreman								+
Praeconosphaera sphaeroconus (Rüst)	+	+
Praexitus alievi (Foreman)				+
Protunuma costata (Heitzer)								+
Pseudoaulophacus ? florealis Jud		+
Pseudodictyomitra cf. carpatica (Loz.)	+
Pseudodictyomitra nodocostata Dum.		+		+
Pseudodictyomitra primitiva M. & Y.								+
Pseudod. pseudomacrocephala (Squin.)							+
Pseudoeucyrtis sp.			+
Pseudoxitus laguncula Dumitrica		+
Saitoum cf. labeosum Dum. & Zügel								+
Sethocapsa sp.	+
Sethocapsa trachyostraca Foreman		+	+	+
Sethocapsa uterculus (Parona)		+		+
Spongocapsula obesa Jud	+
Spongocapsula sp.								+
Suna echiodes (Foreman)		+		+				+
Svinitzium pseudopuga Dumitrica		+	+
Syringocapsa limatum Foreman		+
Tetracapsa sp.				+
Thanarla conica (Aliev)				+
Thanarla cf. gutta					+
Tripocyclia jonesi Pessagno								+
Veghicyclia ? sp.				+
Xitus robustus Wu				+
Xitus sp.			+
Zhamoidellum ovum Dumitrica								+

Note: E2-11-50 Şahvelet area, Erzurum region, near Aziziye, probably Valanginian according to data by Jud (1994), Baumgartner et al. (1995), Dumitrica et al. (1997) and others; E2-11-86 and E2-11-87, Aras Nehri, Şahvelet area, Erzurum region, Hauterivian according to data by Jud (1994), Baumgartner et al. (1995), Dumitrica et al. (1997). E2-11-90 and E2-11-96, same locality, late Hauterivian–early Barremian according to data by Jud (1994), Baumgartner et al. (1995), Dumitrica et al. (1997). E2-11-106, Şahvelet Dağ, Erzurum region, Pliensbachian according to data by Goričan et al. (2006, 2013). E2-11-171, Otlukbeli area, early Turonian according to data by O’Dogherty (1994). E2-11-176, E of Erzincan, late Tithonian according to data by Jud (1994), Baumgartner et al. (1995), Dumitrica et al. (1997). E2-11-177, E of Erzincan, Pliensbachian according to data by Goričan et al. (2006, 2013).

Table 3. (a) and (b) Major, trace element and REE data for basalt, diabase and microgabbro, associated with Early Jurassic ophiolitic rocks of the suture zone (parts A and B). LOI LOI. The samples are basalt except: EZ-11-91A microgabbro dyke in tonalite; EZ-11-21A microgabbro dyke in serpentinite; EZ-11-46 sheeted diabase; EZ-11-95 diabase dyke in serpentinite; EZ-11-23 microgabbro. Locations are listed in Table 1.

Sample	EZ/11/4	EZ/11/9	EZ/11/20	EZ/11/36A	EZ/11/54A	EZ/11/85	EZ/11/89A	EZ/11/96A	EZ/11/101A	EZ/11/108	EZ/11/188	EZ/11/196A	EZ/11/172A	EZ/11/173	EZ/11/174A	EZ/11/95
	IAT-type volcanics												E-MORB-type volcanics			IAT-type isolated dykes
SiO2	51.96	50.73	55.44	45.65	52.23	53.16	51.99	52.89	51.80	45.05	58.45	46.35	43.14	45.20	49.46	51.11
TiO2	1.02	1.13	.59	1.29	1.89	1.32	2.44	1.38	1.76	1.11	1.34	1.51	2.00	2.02	2.13	.51
Al2O3	15.50	16.42	13.21	13.74	14.19	14.07	13.95	14.84	13.92	15.30	13.16	14.19	13.72	14.57	14.65	15.15
FeO^*	11.88	9.33	9.79	9.37	12.76	7.50	13.64	13.21	13.41	11.12	7.88	11.25	11.51	6.77	11.73	8.70
MgO	6.59	5.41	3.90	6.90	4.27	3.95	3.64	4.48	3.77	5.01	3.62	3.82	5.05	3.37	2.47	7.11
MnO	.18	.14	.12	.20	.20	.14	.17	.21	.23	.17	.13	.19	.33	.14	.21	.15
CaO	2.62	8.60	5.87	10.93	6.07	8.36	5.61	7.02	8.91	11.99	5.34	10.30	7.98	10.76	5.83	9.11
Na2O	4.57	4.10	6.14	4.72	3.84	6.42	4.81	4.28	4.67	2.69	4.44	2.75	2.68	3.49	4.36	4.28
K2O	1.69	1.23	.09	.30	.40	.24	.74	.52	.15	.97	.13	.57	2.58	3.30	1.76	.32
P2O5	.09	.13	.05	.11	.15	.14	.25	.12	.18	.11	.13	.14	.33	.28	.38	.03
Cr2O3	<.002	.009	<.002	.023	.003	.014	<.002	.002	<.002	.050	<.002	.003	.012	.014	.004	.016
Total	99.80	99.81	99.88	99.79	99.82	99.87	99.84	99.82	99.86	99.83	99.86	99.84	99.77	99.80	99.81	99.79
LOI	3.7	2.6	4.7	6.6	3.8	4.6	2.6	.9	1.0	6.3	5.2	8.8	10.5	9.9	6.8	3.3
Ni	30	23	22	55	24	37	<20	<20	<20	59	<20	26	39	59	28	53
Sc	35	33	34	40	34	31	36	36	32	44	29	31	30	31	29	37
Ba	189	135	14	63	108	17	94	95	18	46	50	64	186	204	138	96
Co	35.8	31.0	26.8	43.5	32.2	26.3	27.6	34.7	31.5	45.7	33.8	31.9	45.2	34.9	34.6	32.4
Cs	.5	.6	.3	10.8	.7	<.1	<.1	<.1	<.1	.7	<.1	<.1	2.8	2.8	3.5	1.2
Hf	1.7	2.4	1.1	2.3	2.6	2.5	4.4	1.5	2.7	1.8	2.0	2.5	4.4	4.2	4.1	.7
Nb	1.7	5.0	1.0	1.9	2.1	2.6	4.4	1.7	2.8	.8	1.9	2.3	19.7	21.9	21.0	.8
Rb	30.9	26.9	1.2	6.4	9.5	1.5	5.6	8.9	.4	17.7	.9	4.8	35.2	40.2	40.7	7.1
Sr	20.4	212.3	63.3	144.9	159.4	58.5	167.2	32.0	68.1	175.9	93.1	112.9	304.5	321.1	354.8	535.1
Ta	.3	.3	<.1	.1	.1	.2	.2	<.1	.2	<.1	.2	.2	1.2	1.3	1.3	<.1
Th	.2	1.5	.4	.4	.3	.5	.6	.5	.5	<.2	.3	.7	2.1	2.3	2.3	<.2
U	.2	.4	.4	.4	.1	.5	.2	.1	.2	<.1	1.6	.1	.4	1.0	.3	<.1
V	329	237	282	265	366	233	274	320	308	265	324	301	270	222	275	222
Zr	55.9	109.3	31.4	77.8	82.5	88.6	160.4	62.4	104.5	63.3	72.5	91.1	151.9	159.7	156.4	21.0
Y	25.1	26.7	17.5	26.9	33.2	31.9	50.8	22.3	41.6	28.0	28.0	33.5	34.4	30.9	39.3	13.2
Pb	.4	.8	.8	.6	5.9	.6	.1	.8	.3	1.1	.6	1.0	2.2	1.1	3.1	.2
La	2.5	8.1	3.4	4.7	4.7	5.1	7.4	3.6	5.0	2.6	3.0	5.2	18.3	16.0	20.2	1.1
Ce	6.4	18.4	4.9	10.9	11.3	12.6	21.7	9.1	13.1	5.9	9.1	13.1	38.0	34.0	40.2	2.8
Pr	1.15	2.55	.88	1.87	1.93	2.03	3.56	1.45	2.38	1.30	1.60	2.13	5.11	4.70	5.81	.49
Nd	5.4	11.7	4.4	9.6	11.0	10.9	17.3	7.3	12.5	8.3	8.4	10.1	20.7	19.7	25.0	3.2
Sm	2.27	3.28	1.47	3.02	3.21	3.30	5.57	2.19	4.19	2.87	2.74	3.69	4.92	5.03	6.22	1.03
Eu	.85	1.21	.58	1.11	1.27	1.16	2.04	.95	1.53	1.07	1.03	1.29	1.60	1.66	2.14	.43
Gd	3.42	4.25	2.20	3.89	4.59	4.66	7.54	3.10	5.53	3.87	3.76	4.61	5.43	5.41	6.96	1.58
Tb	.64	.73	.38	.65	.76	.76	1.24	.53	.97	.68	.66	.81	.88	.89	1.09	.28
Dy	3.80	4.59	2.82	4.27	5.89	5.09	8.57	3.22	6.55	4.74	4.75	5.93	6.19	5.61	6.66	2.19
Ho	.95	.96	.61	.95	1.15	1.08	1.78	.75	1.45	.95	.99	1.13	1.18	1.07	1.31	.45
Er	2.76	2.76	1.88	2.75	3.17	3.25	5.14	2.41	4.12	2.70	2.77	3.27	3.26	3.00	3.64	1.29
Tm	.39	.43	.31	.39	.51	.50	.74	.35	.61	.42	.44	.47	.50	.43	.53	.20
Yb	2.60	3.13	1.93	2.38	3.38	3.23	5.05	2.35	4.07	2.73	3.05	3.56	3.21	3.15	3.37	1.33
Lu	.41	.44	.31	.37	.48	.47	.75	.35	.60	.39	.44	.48	.44	.43	.46	.21

Sample	EZ/11/15	EZ/11/21A	EZ/11/46	EZ/11/49A	EZ/11/51A	EZ/11/72A	EZ/11/73	EZ/11/74	EZ/11/75A	EZ/11/81	EZ/11/91A	EZ/11/92A	EZ/11/93	EZ/11/102A	EZ/11/6	EZ/11/7A	EZ/11/23
	Boninitic isolated dykes			OIB-type volcanics											Boninitic volcanics		IAT-type microgabbro
SiO2	45.93	43.42	51.16	44.75	47.22	46.08	46.97	43.39	44.80	49.92	42.96	40.54	42.80	41.65	52.59	53.61	44.84
TiO2	.33	.28	.21	3.93	3.73	2.31	2.24	2.68	2.81	2.49	3.65	3.33	4.02	3.91	.18	.26	.46
Al2O3	18.14	15.06	17.42	12.44	12.12	13.99	14.45	15.04	15.86	15.16	13.82	12.26	13.63	12.74	15.09	15.28	16.72
FeO^*	9.30	7.39	7.58	12.45	12.06	9.85	8.92	12.84	14.31	10.64	10.44	11.58	13.60	11.11	5.64	9.16	10.80
MgO	8.25	10.86	6.25	4.84	3.37	2.95	4.27	3.08	3.42	4.32	3.78	5.05	6.86	3.55	8.92	5.92	8.58
MnO	.16	.18	.13	.17	.32	.11	.13	.21	.17	.26	.15	.18	.22	.16	.10	.15	.17
CaO	12.53	17.92	10.77	9.84	9.14	10.36	9.82	10.53	8.01	7.35	10.83	14.08	8.86	12.27	10.62	5.45	11.83
Na2O	1.60	.41	1.86	4.60	4.55	5.48	4.25	3.91	4.31	4.65	4.60	3.23	3.71	4.35	3.86	4.76	1.72
K2O	.24	<.01	.17	.42	.96	.80	1.99	.55	.46	.38	1.32	1.25	.76	1.19	.09	<.01	.03
P2O5	.02	<.01	.02	.47	.47	.43	.43	.46	.43	.56	.65	.56	.60	.58	.02	.03	<.01
Cr2O3	.032	.047	.022	.007	.003	.013	.014	.008	.008	.004	.009	.021	.021	.005	.043	.009	.039
Total	99.79	99.79	99.85	99.72	99.73	99.77	99.71	99.76	99.78	99.77	99.73	99.73	99.67	99.76	99.82	99.84	99.78
LOI	3.3	4.2	4.3	5.8	5.8	7.4	6.2	7.1	5.2	4.0	7.5	7.6	4.6	8.2	2.7	5.2	4.6
Ni	82	166	36	53	47	79	77	46	59	30	27	67	83	57	121	77	46
Sc	43	40	36	25	24	21	21	21	25	19	18	22	26	21	35	37	54
Ba	34	3	45	205	468	144	595	288	197	236	190	221	326	151	19	16	9
Co	42.9	37.9	29.8	40.5	38.8	35.1	39.9	36.3	42.0	30.0	32.5	40.4	47.0	50.8	31.4	34.5	42.0
Cs	<.1	<.1	.3	.4	<.1	.2	<.1	<.1	<.1	<.1	1.0	1.2	.5	1.2	<.1	<.1	<.1
Hf	.2	<.1	.4	5.6	5.1	5.0	4.5	5.2	4.9	5.7	7.6	6.4	7.7	5.7	.3	.5	.4
Nb	.6	.1	.3	42.8	36.9	37.0	33.4	46.1	37.3	49.1	62.2	52.9	63.5	53.9	1.8	1.2	.2
Rb	2.2	.3	1.8	3.9	7.3	12.4	18.6	4.8	4.3	2.4	24.6	26.5	4.8	23.2	2.0	.5	.6
Sr	199.4	78.2	162.3	380.1	289.0	655.4	647.4	395.2	418.2	426.3	435.8	317.9	342.0	300.7	45.5	78.7	133.7
Ta	<.1	<.1	<.1	2.8	2.5	2.2	2.0	2.8	2.2	3.0	3.6	3.3	4.2	3.3	<.1	<.1	<.1
Th	.2	<.2	<.2	3.4	3.5	3.4	3.1	4.3	3.3	4.1	5.8	4.9	5.9	4.5	<.2	.3	<.2
U	<.1	<.1	.1	1.7	.9	1.1	.8	1.1	.8	1.1	2.1	1.3	1.7	1.6	<.1	.1	<.1
V	265	192	209	332	374	197	189	222	248	184	277	293	326	304	186	244	333
Zr	7.3	4.1	13.5	230.8	203.7	179.9	168.5	205.4	186.3	230.3	294.8	251.7	306.0	258.9	12.3	20.9	6.6
Y	8.0	6.6	5.5	28.0	28.1	22.2	22.3	27.8	26.7	30.9	28.6	26.4	29.5	27.1	5.6	7.7	15.6
Pb	.2	.2	.3	2.0	1.9	2.1	1.5	1.2	1.1	1.9	1.5	2.3	1.6	1.3	.3	.4	.1
La	3.4	1.3	1.8	34.1	31.1	30.3	28.2	35.3	27.6	38.3	47.8	41.2	46.6	39.9	1.1	1.6	.7
Ce	2.5	1.5	2.1	72.0	65.9	57.7	55.5	68.4	56.4	77.0	98.4	85.5	98.1	82.9	1.9	2.6	1.8
Pr	.37	.21	.29	9.73	9.07	7.41	7.11	8.70	7.59	9.72	12.57	11.06	12.73	10.80	.24	.34	.40
Nd	1.8	1.2	2.0	41.6	38.6	31.2	29.8	34.8	32.9	39.6	53.0	49.5	51.3	45.6	.8	1.5	2.3
Sm	.56	.61	.41	8.71	8.21	6.08	5.94	6.69	6.17	7.93	9.59	8.69	9.72	8.75	.34	.49	1.24
Eu	.26	.34	.19	2.87	2.64	1.96	2.00	2.17	2.31	2.60	3.04	2.74	3.12	2.56	.15	.20	.40
Gd	.98	.85	.60	8.28	7.91	5.61	5.78	6.55	6.22	7.53	8.48	7.84	8.67	7.67	.60	.84	2.00
Tb	.17	.16	.11	1.04	.98	.74	.74	.91	.86	1.02	1.05	.92	1.10	.99	.11	.16	.36
Dy	1.29	1.30	.92	6.22	5.99	4.60	4.84	5.49	5.53	6.14	6.41	5.68	6.40	5.33	.85	1.10	2.80
Ho	.25	.24	.18	.97	1.06	.78	.77	.99	.93	1.16	.98	.91	.98	.89	.18	.30	.56
Er	.76	.69	.60	2.39	2.51	2.02	2.05	2.66	2.24	2.93	2.58	2.15	2.57	2.12	.74	1.00	1.64
Tm	.13	.12	.08	.35	.34	.30	.26	.37	.32	.41	.34	.29	.34	.32	.11	.16	.26
Yb	.92	.66	.70	2.27	2.21	1.51	1.81	2.47	2.07	2.51	2.20	1.74	2.03	1.68	.81	1.17	1.66
Lu	.13	.10	.10	.27	.28	.24	.27	.35	.27	.36	.28	.25	.27	.24	.13	.17	.25

Note: FeO* means total iron; < below detection limit.

Table 4. Locations where basaltic rocks were collected for chemical analysis.

Sample				Type
EZ-11-4	Zümrüt melange basalt (Kırdağ area)	38T0263656,4492954		IAT
EZ-11-108	Şahvelet, melange basalt (Erzurum area)	37S0726575,4408935		IAT
EZ-11-188	Devekorusu, melange basalt (Erzincan area)	37S0552865,4415874	Pliensbachian	IAT
EZ-11-20	Thrust sheet, basalt (Kırdağ area)	38T0264508,4486179		IAT
EZ-11-96A	Şahvelet, melange basalt (Erzurum area)	37S0736984,4410532		IAT
EZ-11-36A	Muratbağı, melange basalt (Horasan area)	38T 0247301,4450147		IAT
EZ-11-54A	Aziziye area, melange basalt (Erzurum area)	37S0697649,4410054		IAT
EZ-11-101A	Şahvelet, melange basalt (Erzurum area)	37S0731482,4407114		IAT
EZ-11-85	Şahvelet, melange basalt (Erzurum area)	37S5073620,4412626		IAT
EZ-11-196A	Basalt, melange, Refahiye area	37S0454672,441707	Hauterivian	IAT
EZ-11-89A	Aras Çay melange basalt (Erzurum area)	37S0736838, 4410990		IAT
EZ-11-9	Zümrüt melange basalt (Kırdağ area)	37S0454998,4417696	Hauterivian	IAT
EZ-11-173	Otlukbeli melange basalt (Bayburt)	37T6583891,4429139		E-MORB
EZ-11-172A	Otlukbeli melange basalt (Bayburt)	37T6583891,4429139	Lower Turonian	E-MORB
EZ-11-174A	Otlukbeli melange basalt (Bayburt)	37T6583891,4429139	Lower Turonian	E-MORB
EZ-11-75A	Aktaş Tepe, melange basalt, Horasan area	38T0261140, 4465281	Lower Turonian	OIB
EZ-11-73	Pamukdere, melange basalt, Horasan area	38T0261518,4464891		OIB
EZ-11-72A	Pamukdere, melange basalt, Horasan area	38T0261518,4464891		OIB
EZ-11-51A	Aziziye area, melange, basalt (Erzurum area)	37S0696910,4409755		OIB
EZ-11-49A	Aziziye area, melange, basalt (Erzurum area)	37S0696910,4409755	Valanginian	OIB
EZ-11-74	Pamukdere, melange basalt, Horasan area	38T0261518,4464891		OIB
EZ-11-81	Çatalelma, melange basalt (Kırdağ area)	38T0272827,4481788		OIB
EZ-11-102A	Akpınar, melange basalt, Horasan area	38T0731482,4407114		OIB
EZ-11-92A	Aras Çay melange, melange basalt (Erzurum area)	37S0737846,4408428		OIB
EZ-11-93	Aras Çay melange, melange basalt (Erzurum area)	37S0737846,4408428		OIB
EZ-11-176	Main road E of Erzincan, meleange basalt	37S0578705,4381998		OIB
EZ-11-177	Main road E of Erzincan	37S0575442,4382608	Late Tithonian	OIB
EZ-11-91A	Aras Çay melange, melange basalt (Erzurum area)	37S0737846,4408428	Hauterivian	OIB
EZ-11-15	Microgabbro dyke in tonalite (Kırdağ area)	38T0267599,4490067		Boninite
EZ-11-21A	Microgabbro dyke in sepentinite (Kırdağ area)	38T0264508,4486179		Boninite
EZ-11-46	Sheeted diabase, Dönertaş (Horasan area)	38T03254916,445669		Boninite
EZ-11-95	Diabase dyke in serpentinite, Şahvelet (Erzurum)	37S0736984,4410532		IAT
EZ-11-6	Zümrüt melange basalt (Kırdağ area)	38T0263656,4492954		Boninite
EZ-11-23	Microgabbro slice (Kırdağ area)	38T0265774,4485382		IAT
EZ-11-7A	Zümrüt, melange basalt (Kırdağ area)	38T0263656,4492954		Boninite

Notes: Column 1 Sample number; column 2 locality and lithology; column 3 UTM co-ordinates given as UMT (WGS 84). Samples EZ-11-176 and 177 are radiolarites that are associated with OIB-type lavas, as previously reported by Rice et al. (2009) and Parlak, Çolakoğlu, et al. (2013).

Table 5. Summary of the chemical data obtained by ion probe analysis. The uncorrected and corrected U–Pb isotopic ratios were used to calculate the Early Jurassic radiometric ages.

	U	Th	Pb	Th/U	204Pb	f206	Corrected						Uncorrected				rho	Age
	ppm wt	ppm wt	ppm wt	atomic	ppb wt	(%)	207/206	1s	207/235	1s	206/238	1s	238/206	1s	207/206	1s		206/238	1s	207/235	1s
179D1	247.5	112.6	7.4	.467	3.0	.92	.0478	.0013	.1898	.0055	.0288	.0004	34.4	.4	.0550	.0013	.4286	183.1	2.3	176.4	4.7
179H1	602.7	455.7	19.8	.776	3.1	.38	.0470	.0006	.1899	.0032	.0293	.0003	34.0	.4	.0500	.0006	.6960	186.3	2.1	176.5	2.7
179C1	557.9	332.8	17.2	.612	1.2	.16	.0503	.0006	.1986	.0033	.0286	.0004	34.9	.4	.0516	.0006	.7514	182.0	2.2	184.0	2.8
179A1	529.1	272.9	15.9	.529	3.1	.43	.0502	.0007	.1980	.0038	.0286	.0004	34.8	.4	.0536	.0007	.6609	181.8	2.3	183.4	3.2
179E2	777.3	579.9	25.2	.765	6.5	.62	.0482	.0006	.1934	.0032	.0291	.0003	34.2	.4	.0531	.0006	.7236	184.8	2.2	179.5	2.7
24C	130.8	61.0	3.8	.479	1.7	.98	.0488	.0019	.1891	.0077	.0281	.0003	35.2	.4	.0565	.0019	.2834	178.8	2.0	175.9	6.6
24D	166.9	81.7	4.9	.502	1.0	.45	.0467	.0013	.1827	.0057	.0283	.0004	35.1	.4	.0503	.0013	.4152	180.2	2.3	170.4	4.9
24E	243.3	108.7	7.0	.458	3.6	1.16	.0471	.0009	.1818	.0042	.0280	.0004	35.3	.5	.0562	.0009	.5878	178.0	2.4	169.6	3.6
24G	74.5	33.0	2.1	.455	.3	.28	.0456	.0015	.1743	.0061	.0277	.0004	35.9	.5	.0478	.0015	.3809	176.4	2.3	163.2	5.2
24H	638.3	804.6	23.0	1.293	3.7	.44	.0478	.0007	.1881	.0036	.0285	.0003	34.9	.4	.0512	.0007	.5933	181.3	2.0	175.0	3.1
24 J	247.0	147.4	7.7	.612	.0	.01	.0512	.0010	.2032	.0049	.0288	.0004	34.7	.5	.0512	.0010	.5662	182.9	2.4	187.9	4.1
24 K	211.3	133.1	6.4	.646	.9	.31	.0481	.0011	.1860	.0047	.0281	.0004	35.5	.4	.0506	.0011	.4981	178.4	2.2	173.2	4.0
59A	262.9	177.5	8.4	.693	2.4	.67	.0485	.0010	.1942	.0048	.0291	.0004	34.2	.4	.0538	.0010	.4934	184.7	2.2	180.2	4.1
59B	317.7	115.8	9.4	.374	.4	.10	.0498	.0008	.2016	.0041	.0294	.0004	34.0	.4	.0506	.0008	.6070	186.6	2.3	186.5	3.4
59C	40.3	11.2	1.2	.286	.2	.41	.0512	.0026	.2072	.0109	.0294	.0004	33.9	.4	.0544	.0026	.2385	186.5	2.3	191.2	9.2
59D	81.5	26.4	2.4	.333	.2	.21	.0455	.0019	.1841	.0079	.0294	.0004	34.0	.5	.0471	.0019	.3193	186.6	2.5	171.6	6.8
59E	270.9	91.6	7.8	.347	.8	.23	.0473	.0005	.1877	.0031	.0288	.0003	34.6	.4	.0491	.0005	.7174	183.1	2.2	174.7	2.7
59F	252.7	194.1	8.4	.788	.8	.24	.0477	.0009	.1953	.0044	.0297	.0004	33.6	.4	.0495	.0009	.5632	188.8	2.3	181.2	3.7
59G	59.3	17.6	1.7	.304	.5	.62	.0460	.0013	.1866	.0062	.0294	.0005	33.8	.5	.0509	.0013	.4680	186.9	2.8	173.7	5.3
62A	1467.2	886.1	44.3	.620	1.9	.10	.0494	.0004	.1908	.0027	.0280	.0003	35.6	.4	.05016	.0004	.8408	178.1	2.1	177.3	2.3
62B	528.7	201.6	15.0	.391	1.6	.24	.0485	.0007	.1868	.0034	.0280	.0003	35.7	.4	.05036	.0007	.6288	177.7	2.0	173.9	2.9
62C	1125.0	723.0	34.3	.659	1.4	.10	.0490	.0003	.1891	.0024	.0280	.0003	35.7	.4	.04970	.0003	.8948	178.1	2.0	175.8	2.0
62D	820.8	363.2	23.6	.454	5.1	.48	.0482	.0005	.1850	.0028	.0278	.0003	35.8	.4	.05201	.0005	.7711	176.9	2.0	172.4	2.4
62E	879.3	399.2	25.7	.466	4.3	.38	.0485	.0003	.1893	.0026	.0283	.0003	35.2	.4	.05146	.0003	.8579	179.8	2.1	176.0	2.2
78A	49.5	12.0	1.4	.248	.4	.57	.0473	.0027	.1832	.0109	.0281	.0005	35.4	.6	.0518	.0027	.2901	178.5	3.0	17.8	9.3
78A2	143.2	17.9	3.5	.128	3.2	1.86	.0512	.0023	.1839	.0085	.0261	.0003	37.6	.5	.0657	.0023	.2642	165.9	2.0	171.4	7.3
78B	25.7	5.3	.7	.212	.2	.65	.0509	.0031	.1912	.0129	.0272	.0008	36.5	1.0	.0561	.0031	.4284	173.1	4.9	177.6	10.9
78C	24.1	4.3	.6	.185	.3	.94	.0404	.0038	.1471	.0143	.0264	.0006	37.5	.9	.0479	.0038	.2442	167.9	3.9	139.3	12.6
79C1	1565.0	1655.7	54.9	1.085	2.0	.10	.0486	.0003	.1954	.0027	.0291	.0004	34.3	.4	.0494	.0003	.8795	185.1	2.2	181.2	2.3
79D1	2349.2	3480.1	91.5	1.520	2.6	.08	.0489	.0002	.1986	.0026	.0294	.0004	33.9	.4	.0496	.0002	.9306	187.0	2.3	183.9	2.2
79E1	1459.7	1094.6	49.0	.769	1.4	.07	.0498	.0004	.2061	.0030	.0300	.0004	33.3	.4	.0503	.0004	.8513	190.6	2.3	190.3	2.5
79F1	846.7	615.3	27.5	.745	3.9	.34	.0471	.0004	.1900	.0029	.0293	.0004	34.0	.4	.0498	.0004	.8287	185.9	2.3	176.6	2.4
79G1	608.1	265.0	17.7	.447	5.2	.65	.0490	.0011	.1913	.0051	.0283	.0004	35.1	.4	.0542	.0011	.4709	179.8	2.2	177.7	4.3
79H1	717.2	447.3	22.3	.640	3.4	.36	.0475	.0005	.1879	.0032	.0287	.0004	34.7	.4	.0503	.0005	.7418	182.4	2.3	174.9	2.7
80B1	45.6	16.2	1.3	.364	.6	.98	.0475	.0034	.1866	.0140	.0285	.0005	34.8	.6	.0553	.0034	.2511	181.1	3.4	173.7	11.9
80C1	39.2	14.9	1.2	.389	1.5	2.83	.0529	.0042	.2144	.0175	.0294	.0005	33.1	.5	.0751	.0042	.2030	186.7	3.0	197.2	14.5
80D1	57.8	24.0	1.7	.426	.4	.52	.0526	.0017	.2110	.0074	.0291	.0005	34.2	.5	.0566	.0017	.4494	184.9	2.9	194.4	6.2
80D2	18.0	5.3	.5	.304	.6	2.70	.0438	.0056	.1699	.0221	.0282	.0008	34.6	.9	.0652	.0056	.2111	179.0	4.8	159.4	19.0
80F1	50.7	17.6	1.4	.356	.7	1.05	.0544	.0023	.2112	.0099	.0281	.0005	35.2	.7	.0627	.0023	.4151	178.9	3.4	194.5	8.2

Figure 28(B). Micopalaeontological evidence. Late Cretaceous planktic foraminifera and Miocene large foraminifera. (a–b) Hedbergella sp., sample 165, Otlukbeli area, Late Cretaceous; (c) Archaeoglobigerina cretacea (d’Orbigny), sample 112; (d) Schackoina multispinata (Cushman & Wickenden), sample 114; (e) Globotruncanella petaloidea (Gandolfi), sample 58; (c–e) Şahvalet area; near Aziziye; (f) Globotruncana bulloides Vogler, sample 43A; Horasan area; near Yatıksırt); (g) Rugoglobigerina rugosa (Plummer), sample 68; (h) Planoglobulina carseyae (Plummer), sample 68; Horasan area; W of Akören; (i) Globotruncana orientalis El Naggar, sample 111; Şahvalet area; near Aziziye; (j) Rugoglobigerina milamensis Smith & Pessagno, sample 34a; Horasan area; near Kalendere; (k) Globotruncanita pettersi (Gandolfi), sample 68; (l) Racemiguembelina fructicosa (Egger), sample 68; Horasan area; W of Akören; (m) Abatomphalus mayaroensis (Bolli), sample 35A; Horasan area; near Kalendere; (n–p) Miocene benthic foraminifera, n: Operculina complanata (Defrance) (O), Amphistegina lessonii (d’Orbigny) (A), coralline alga (C), sample 175; E of Erzincan, main road sectional o: Borelis sp., sample 88; Şahvalet area; W bank of Aras Çay; p: Miolepidogypsina sp., sample 178; NE of Erzincan; S of Kapılıdağ. Scale bars: .2 mm.

Figure 29. Cross-section and sedimentary log of Jurassic–Cretaceous sedimentary succession within imbricate thrust sheets to the SE of the Kırdağ massif (see Figure 18 for location). In general, Early Cretaceous neritic limestones and siltstones/mudrocks are overlain by Upper Cretaceous volcanogenic siltstone and fine-grained sandstones.

Figure 30. Cross-section showing interslicing of Cretaceous Eurasian margin-related sediments with ophiolitic rocks; Horasan area (see Figure 6). The Eurasian margin units are tectonically dismembered, while the intact sequences include interbedded debris-flow deposits.

Figure 31. Highest stratigraphical levels of the Eurasian margin carbonate platform and overlying volcanic-sedimentary melange (near Otlukbeli, W of Bayburt; (a) Outline geological map (modified from Bozkuş & Yılmaz, l993); (b) Cross-section A–A′. The highest stratigraphical levels of the platform are dated here as Campanian–Maastrichtian using planktic foraminifera; (c) Dismembered thrust sheet (large block) within the volcanic-sedimentary melange in the SE of the area (B–B′). (see Figure 3; compiled from Korkmaz & Baki, l984, Özer, l984 and this study).

Figure 32. Upper Cretaceous and Cenozoic successions exposed along the northern margin of the Kırdağ massif. Upper: cross-section. The small offset section shows a contrasting relationship several kilometres to the SW where the Lower Eocene succession is unconformably overlain by Oligo-Miocene sediments and volcanics. Lower left, summary logs (1–6) with locations marked on the cross-section above. Data from this study (see Figure 18 for location).

Figure 33. Simplified geological map of a key area of the Eurasian margin to the north of the suture zone, NW of Olur. Left: outline map showing lines of sections; Right: upper, Summary measured log (composite of logs a and b on the map; this study); Right lower, cross-section (marked A–A′ on the map). (U. Eo Upper Eocene; M. Eo. Middle Eocene). An Upper Cretaceous marine, mixed carbonate/volcanogenic succession passes into Upper Palaeocene shallow-water mixed carbonates and clastics. This sequence was transgressed by Middle-Upper Eocene non-marine, shallow-marine and then deeper-marine (marls) sediments. The shelf carbonates are intercalated with basaltic extrusions (see Figure 3; compiled from Konak & Hakyemez, 2008a and this study; see also Bozkuş, l992a, 1992b).

Figure 34. Relationship of the Munzur carbonate platform (part of the Taurides) to the suture zone in the southwest of the area studied. For the line of the main cross-section see Figure 3. The small cross-section (above, center) shows an outcrop on strike to the E where basalt and cherty pelagic limestone are also exposed. The Karadağ Massif is interpreted as part of the Eurasian continental margin, which was imbricated with volcanic-sedimentary melange during collision-related out-of-sequence thrusting.

Figure 35. Influence of Plio–Quaternary strike-slip related to the North Anatolian Transform Fault, as seen along the NE margin of the ophiolite in the Erzincan area. Ophiolitic peridotite is juxtaposed with the volcanic-sedimentary and ophiolitic melange by a strike-slip fault. Another strike-slip fault separates the melange from the Eurasian carbonate platform to the north. The Oligocene–Miocene cover of both the ophiolite and the melange was folded (Late Miocene?) prior to Plio–Quaternary fault displacement.

Figure 36. Tectono-stratigraphic comparison. (a) Central Pontides (see Figure 3 for line of section). One important unit, the Upper Cretaceous arc apron/forearc basin sediments (Yapraklı Formation) is exposed ~20 km west of the section, while the largest ophiolite outcrop (type Kızılırmak ophiolite) is exposed 50 km northeast of the line of section; (b) Eastern Pontides (see Figure 3 for line of section). This section is representative of the western part of the Eastern Pontide region (around Erzincan), where the oceanic units dip below Eurasian continental margin units. In contrast, the structure of more easterly areas of the Eastern Pontide was strongly influenced by post-collisional northward thrusting. (a–b) Modified after Rice et al. (2006) (c) Lesser Caucasus. ci, well-documented example of imbricate thrust belt within the western exposure of the Sevan–Akera suture zone (simplified from Hässig et al., 2013); cii, isolated klippen of oceanic rocks ~50 km SW of the main Sevan–Akera suture zone; thrust over the northernmost outcrop of the South Armenian crustal unit (simplified from Sosson et al., 2010). See text for discussion.

Figure 37. Emplacement of accretionary melange over the collapsed southern margin of Eurasia represented by the Pontide carbonate platform (near Otlukbeli, SW of Bayburt; see Figure 3 for location). The uppermost levels of the platform comprise pelagic and redeposited carbonates that were are dated as Campanian–Maastrichtian during this study (see Figure 31). The platform succession terminates with siltstone/fine-grained sandstone turbidites with reworked Early Cretaceous benthic foraminifera. Folds in the carbonate platform indicate top-N displacement. The lowest levels of the melange contain blocks of lithologies that are similar to those exposed in the highest levels of the platform (i.e. Campanian–Maastrichtian-aged pelagic and silty redeposited carbonates).

Figure 38. Mid- to Late Eocene post-collisional basin located in the northeast (Olur area; see Figure 3). The basin records subsidence soon after the final ocean basin suturing. More distal successions are exposed along the Black Sea coast, suggesting that the Eastern Black Sea basin also experienced a rift event during Mid-Late Eocene time. Similar basins of this age developed throughout the Pontides and the Lesser Caucasus. See text for discussion.

Figure 39. Three alternative models for the Early Jurassic of SSZ oceanic crust. Option b (favoured) is developed in Figure 40. (a) Single subduction zone dipping beneath the Pontide continental margin. ai, The ophiolite forms by SSZ spreading, coupled with rifting (extension) of the Eurasian margin. The dyke swarms cutting metasediments (beneath the Refahiye ophiolite; see Figure 19) are explained by initiation of spreading along the Eurasian margin; aii, A colliding crustal block (continental fragments or igneous seamount) is invoked to explain the well-documented closure of the backarc rift and deformation of the Eurasian continental margin during the Late Jurassic; (b) Two N-dipping subduction zones, one oceanic and one adjacent to the Pontide margin. Older oceanic crust (Palaeotethys) is subducted to create the Jurassic backarc rift and arc. bi, The Early Jurassic oceanic crust is generated by SSZ spreading in a more oceanic setting. A crustal block is again invoked to explain the origin of the dyke swarms (as in ai); bii, the inferred continental fragment collides with the Eurasian margin leading to closure of the backarc rift; (c) Single S-dipping subduction zone. ci, Intra-oceanic subduction possibly initiates along the margin of a crustal block. Slab-pull might help explain the Jurassic continental margin magmatism (but not its subduction-related chemical affinities). cii, Southward subduction culminates in collision and emplacement over the Eurasian margin during the Late Cretaceous. Some accretionary melange was indeed emplaced over the Eurasian margin during the Late Cretaceous but evidence for large-scale ophiolite obduction is absent. Each of the above models has some pros and cons as discussed in the text.

Figure 40. Proposed double subduction zone tectonic model for the Mesozoic-Palaeogene development of the suture zone in the Eastern Pontides, E Turkey. See text for explanation.

Ustaömer, T., & Robertson, A. H. F. (2010). Late Paleozoic–Early Cenozoic tectonic development of the eastern Pontides (Artvin area), Turkey: Stages of closure of Tethys along the southern margin of Eurasia. In M. Sosson, N. Kaymakçı, R. A. Stephenson, F. Bergerat, & V. Starostenko (Eds.), Sedimentary basin tectonics from the Black Sea and Caucasus to the Arabian platform (Vol. 340, pp. 281–327). London: Geological Society, Special Publications.

 Google Scholar

MTA. (2002). 1:500,000 ölçekli Türkiye jeoloji haritası [Geological map of Turkey, 1:500,000]. MadenTektik ve Arama Genel Müdürlüğü [General Directorate of Mineral Research and Exploration]. Ankara.

 Google Scholar

Parlak, O., Çolakoğlu, A., Dönmez, C., Sayak, H., Yıdırım, N., Türkel, A., & Odabaşı, I. (2013). Geochemistry and tectonic setting of ophiolites along the İzmir–Ankara–Erzincan Suture Zone in northeastern Anatolia. In A. H. F. Robertson, O. Parlak, & U.-C. Ünlügenç (Eds.), Geological development of Anatolia and the easternmost Mediterranean (Vol. 372, pp. 75–106). London: Geological Society, Special Publications.

 Google Scholar

Tarhan, N. (1988). 1/100.000 Ölçekli Türkiye jeoloji haritaları serisi, Erzurum-F31 (~İ 45) paftası [1/100.000 scale Turkish geology map series, Erzurum-F31 (~İ 45) sheet] (Vol. 56, 13 pp.). Ankara: General Directorate of Mineral Research and Exploration, Geology Department.

 Google Scholar

Yılmaz, A., Terlemez, İ., & Uysal, Ş. (1986). Erzurum güneydoğusunda yer alan Hınıs, Tekman ve Karayazı arasının jeolojisi [Geology of the area between Hınıs, Tekman and Karayazı at southeast of Erzurum] (Report 8089). Ankara: General Directorate of Mineral Research and Exploration (MTA).

 Google Scholar

Yılmaz, A., Terlemez, İ., & Uysal, Ş. (1988a). Hınıs (Erzurum güneydoğusu) dolayının bazı stratigrafik ve tektonik özellikleri [Some stratigraphic and tectonic characteristics of the area around Hınıs (southeast of Erzurum]. Bulletin of the Mineral Research and Exploration, 108, 1–22.

 Google Scholar

Yılmaz, A., Terlemez, I., & Uysal, Ş. (1988c). 1/100.000 Ölçekli Türkiye jeoloji haritaları serisi, Erzurum-F33 (~I 47) paftası [1/100.000 scale Turkish geology map series, Erzurum-F33] (25 pp.). Ankara: General Directorate of Mineral Research and Exploration, Geology Department.

 Google Scholar

Yılmaz, A., Terlemez, İ., & Uysal, Ş. (1989). Erzurum güneydoğusu Sakaltutan Dağı yöresinin jeolojisi [Geology of Sakaltutan region to the southeast of Erzurum] (Report 8903). Ankara: General Directorate of Mineral Research and Explorationara.

 Google Scholar

Yılmaz, A., Terlemez, İ., & Uysal, Ş. (1988b). Sakaltutan Dağı civarındaki ofiyolitik birimlerin jeolojik özellikleri ve yapısal evrimi [Geological characteristics and structural evolution of the ophiolitic units around Sakaltutan Dağı (Erzurum)]. METU Journal of Pure and Applied Sciences, 21, 221–235.

 Google Scholar

Yılmaz, A., & Uysal, Ş. (1988). 1/100.000 Ölçekli Türkiye jeoloji haritaları serisi, Erzurum-F33 paftası [1/100.000 scale Turkish geology map series, Erzurum-F34] (20 pp.). Ankara: General Directorate of Mineral Research and Exploration, Geology Department.

 Google Scholar

Konak, N., & Sümengen, M. (2009). 1/100.000 Ölçekli Türkiye jeoloji haritaları serisi, Kars-H48 paftası [1/100.000 scale Turkish geology map series, Kars-H48 sheet] (Vol. 106, 23 pp.). Ankara: General Directorate of Mineral Research and Exploration, Geology Department.

 Google Scholar

Aktimur, H. T., Yurdakul, M. E., Sarıaslan, M., Göksel, M., Keçer, M., Yıldırım, T., & Akkuş, İ. (1995). Geology of Erzincan region and petrology of Quaternary volcanic rocks. In A. Erler (Ed.), Geology of the Black Sea region (pp. 82–90). Ankara: General Directorate of Mineral Research and Exploration and Chamber of Geological Engineers.

 Google Scholar

Tarhan, N. (2007a). 1/100.000 Ölçekli Türkiye jeoloji haritaları serisi, Erzincan-İ 44) paftası [1/100.000 scale Turkish geology map series, Erzincan-İ 44 sheet] (Vol. 67, 31 pp.). Ankara: General Directorate of Mineral Research and Exploration, Geology Department.

 Google Scholar

Tarhan, N. (2007b). 1/100.000 Ölçekli Türkiye jeoloji haritaları serisi, Erzincan-İ 43 paftası [1/100.000 scale Turkish geology map series, Erzincan-İ43 sheet] (Vol. 68, 36 pp.). Ankara: General Directorate of Mineral Research and Exploration, Geology Department.

 Google Scholar

Pearce, J. A. (1996). A users guide to basalt discrimination diagrams. In D. A. Wyman (Ed.), Trace element geochemistry of volcanic rocks: Applications for massive sulphide exploration (Vol. 12, pp. 79–113). Geochemistry, Geological Association of Canada, Short Course Notes, St. John’s, Newfoundland.

 Google Scholar

Sun, S. S., & Mcdonough, W. F. (1989). Chemical and isotopic systematics of ocean basalts: Implications for mantle composition and processes. In A. D. Saunders & M. J. Norry (Eds.), Magmatism in the ocean basins (Vol. 42, pp. 313–347). London: Geological Society, Special Publications.

 Google Scholar

Konak, N., Hakyemez, H. Y., Bilgiç, T., Bilgin, R., Hepşen, N., & Ercan, T. (2001). Kuzeydoğu Pontidlerin (Oltu-Olur-Şenkaya-Narman-Uzundere-Yusufeli) Jeolojisi [Geology of northeast Pontides (Oltu-Olur-Şenkaya-Narman-Uzundere-Yusufeli)] (Report 10489). Ankara: General Directorate of Mineral Research and Exploration (MTA).

 Google Scholar

Konak, N., & Hakyemez, H. Y. (2008b). 1/100.000 Ölçekli Türkiye jeoloji haritaları serisi, Tortum-H47 paftası [1/100.000 scale Turkish geology map series, Tortum-H47 sheet] (Vol. 95, 46 pp.). Ankara: General Directorate of Mineral Research and Exploration, Geology Department.

 Google Scholar

Konak, N., & Hakyemez, H. Y. (2008a). 1/100.000 Ölçekli Türkiye jeoloji haritaları serisi, Kars-G48 paftası [1/100.000 scale Turkish geology map series, Kars-G48 sheet ] (Vol. 104, 69 pp.). Ankara: General Directorate of Mineral Research and Exploration, Geology Department.

 Google Scholar

Tarhan, N. (2008). 1/100.000 Ölçekli Türkiye jeoloji Haritaları serisi, Erzincan-İ 42 paftası [1/100.000 scale Turkish geology map series, Erzincan-İ 42 sheet] (Vol. 84, 27 pp.). Ankara: General Directorate of Mineral Research and Exploration, Geology Department.

 Google Scholar

Rice, S. P., Robertson, A. H. F., & Ustaömer, T. (2006). Late Cretaceous–early Ceneozoic tectonic evolution of the Eurasian active margin in the Central and Eastern Pontides, northern Turkey. In A. H. F. Robertson & D. Mountrakis (Eds.), Tectonic development of the Eastern Mediterranean region (Vol. 260, pp. 413–444). London: Geological Society, Special Publications.

 Google Scholar

Topuz, G., Göçmengil, G., Rolland, Y., Çelik, O. F., Zack, T., & Schmitt, A. K. (2013). Jurassic accretionary complex and ophiolite from northeast Turkey: No evidence for the Cimmerian continental ribbon. Geology, 41, 255–258.10.1130/G33577.1

 Web of Science ®Google Scholar

Okay, A. İ., & Şahintürk, Ö. (1997a). Geology of the Eastern Pontides. In A. G. Robınson (Ed.), Regional and petroleum geology of the Black Sea and surrounding region (Vol. 68, pp. 291–311). Houston, TX: American Association of Petroleum Geologists Memoir.

 Google Scholar

Jud, R. (1994). Biochronology and systematics of Early Cretaceous Radiolaria of the Western Tethys (Vol. 19, 1–147). Lausanne: Mémoires de Géologie.

 Google Scholar

Baumgartner, P. O., O’Dogherty, L., Gorican, S., Dumitrica-Jud, R., Dumitrica, P., Pillevuit, A., … Steiger, T. (1995). Radiolarian catalogue and systematics of Middle Jurassic to Early Cretaceous Tethyan genera and species. In P. O. Baumgartner, L. O’Dogherty, S. Gorican, E. Urquhart, A. Pillevuit, & P. DeWever (Eds.), Middle Jurassic to Lower Cretaceous Radiolaria of Tethys: Occurrences, systematics, biochronology (Vol. 23, pp. 37–688). Lausanne: Memoires de Géologie.

 Google Scholar

Dumitrica, P., Immenhauser, A., & Dumitrica-Jud, R. (1997). Mesozoic radiolarian biostratigraphy from Masirah Ophiolite, Sultanate of Oman. Part I: Middle Triassic, uppermost Jurassic and lower Cretaceous Spumellarians and multisegmented Nassellarians. Bulletin of the National Museum of Natural Science, 9, 1–106. Taichung, Taiwan.

 Google Scholar

Goričan, S., Carter, E. S., Dumitrica, P., Whalen, P. A., Hori, R. S., De Wever, P., … Guex, J. (2006). Catalogue and systematic of Pliensbachian, Toarcian and Aalenian radiolarian genera and species (p. 446). Ljubljana: Založba ZRC.

 Google Scholar

Goričan, Š., Carter, E. S., Guex, J., O’Dogherty, L., De Wever, P., Dumitrica, P., Matsuoka, P. A. (2013). Evolutionary patterns and palaeobiogeography of Pliensbachian and Toarcian (Early Jurassic) Radiolaria. Palaeogeography, Palaeoclimatology, Palaeoecology, 386, 620–636.10.1016/j.palaeo.2013.06.028

 Google Scholar

O’Dogherty, L. (1994). Biochronology and paleontology of mid-Cretaceous radiolarians from Northern Apennines (Italy) and Betic Cordillera (Spain). Mémoires de Géologie (Lausanne), 21, 1–413.

 Google Scholar

Rice, S. P., Robertson, A. H. F., Ustaömer, T., İnan, N., & Tasli, K. (2009). Late Cretaceous–Early Eocene tectonic development of the Tethyan suture zone in the Erzincan area, Eastern Pontides, Turkey. Geological Magazine, 146, 567–590.10.1017/S0016756809006360

 Web of Science ®Google Scholar

Bozkuş, C., & Yılmaz, Ö. (l993). Tercan (Erzincan) ve Aşkale (Erzurum) arasındaki bölgenin tektoniği [Tectonics of the region between Tercan (Erzincan) and Aşkale (Erzurum)]. Türkiye Jeoloji Bülteni [Geological Bulletin of Turkey], 36, 189–201.

 Google Scholar

Korkmaz, S., & Baki, Z. (1984). Demirözü (Bayburt) güneyinin stratigrafisi [Stratigrapy of the south of Demirözü (Bayburt) area]. Geological Bulletin of Turkey, 5, 107–115.

 Google Scholar

Bozkuş, C. (1992a). Olur (Erzurum) yöresinin stratigrafisi [Stratigraphy of the Olur (Erzurum) region]. Türkiye Jeoloji Bülteni [Geological Bulletin of Turkey], 35, 103–119.

 Google Scholar

Bozkuş, C. (1992b). Oltu-Narman (Erzurum) Tersiyer havzası kuzeydoğusunun (Kömürlü) stratigrafisi [Stratigraphy of the northeastern part of Oltu-Narman (Erzurum) Tertiary basin], Türkiye Jeoloji Bülteni [Geological Bulletin of Turkey], 33, 47–56.

 Google Scholar

Hässig, M., Rolland, Y., Sosson, M., Galoyan, G., Müller, C., Avagyan, A., & Sahakyan, L. (2013). New structural and petrological data on the Amasia ophiolites (NW Sevan–Akera suture zone, Lesser Caucasus): Insights for a large-scale obduction in Armenia and NE Turkey. Tectonophysics, 588, 135–153.10.1016/j.tecto.2012.12.003

 Google Scholar

Sosson, M., Rolland, Y., Danelian, T., Muller, C., Melkonyan, R., Adamia, S., … Galoyan, G. H. (2010). Subductions, obduction and collision in the Lesser Caucasus (Armenia, Azerbaijan, Georgia), new insights. In M. Sosson, N. Kaymakci, R. Stephanson, F. Bergarat, & V. Storatchenoko (Eds.), Sedimentary basin tectonics from the Black Sea and Caucasus to the Arabian Platform (Vol. 340, pp. 329–352). London: Geological Society, Special Publications.

 Google Scholar