The Mamonia Complex (SW Cyprus) Revisited: Remnant of Late Triassic Intra-Oceanic Volcanism Along the Tethyan Southwestern Passive Margin

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Geol. Mag. 144 (1), 2007, pp. 1–19. c 2006 Cambridge University Press 1 doi:10.1017/S0016756806002937 First published online 21 December 2006 Printed in the United Kingdom The Mamonia Complex (SW Cyprus) revisited: remnant of Late Triassic intra-oceanic volcanism along the Tethyan southwestern passive margin

H. LAPIERRE∗, D. BOSCH‡, A. NARROS∗, G. H. MASCLE∗§, M. TARDY ¶ & A. DEMANT ∗Laboratoire Geodynamique´ des Chaˆınes Alpines, UMR-CNRS 5025, Universite´ J. Fourier, Maison des Geosciences,´ B. P. 53, F. 38041 Grenoble Cedex, France ‡Laboratoire de Tectonophysique, UMR-CNRS 5568, Institut des Sciences de la Terre, de l’Eau et de l’Espace de Montpellier, CC049, Universite´ de Montpellier II, Place Eugene` Bataillon, F. 34095 Montpellier Cedex 05, France ¶Laboratoire Geodynamique´ des Chaˆınes Alpines, UMR-CNRS 5025, Universite´ de Savoie, F. 73376 Le Bourget du Lac, France Laboratoire de Petrologie´ magmatique, Universite´ Paul Cezanne´ (Aix-Marseille), case courrier 441, F. 13397 Marseille Cedex 20, France

(Received 21 June 2005; accepted 11 May 2006)

Abstract – Upper Triassic volcanic and sedimentary rocks of the Mamonia Complex in southwestern Cyprus are exposed in erosional windows through the post-Cretaceous cover, where the Mamonia Complex is tectonically imbricated with the Troodos and Akamas ophiolitic suites. Most of these Upper Triassic volcanic rocks have been considered to represent remnants of Triassic oceanic crust and its associated seamounts. New Nd and Pb isotopic data show that the whole Mamonia volcanic suite exhibits features of oceanic island basalts (OIB). Four rock types have been distinguished on the basis of the petrology and chemistry of the rocks. Volcanism began with the eruption of depleted olivine tholeiites (Type 1) and oceanic island tholeiites (Type 2) associated with deep basin siliceous and/or calcareous sediments. The tholeiites were followed by highly phyric alkali basalts (Type 3) interbedded with pelagic Halobia-bearing limestones or white reefal limestones. Strongly LREE-enriched trachytes (Type 4) were emplaced during the final stage of volcanic activity. Nd and Pb isotopic ratios suggest that tholeiites and mildly alkali basalts derived from partial melting of heterogeneous enriched mantle sources. Fractional crystallization alone cannot account for the derivation of trachytes from alkaline basalts. The trachytes could have been derived from the partial melting at depth of mafic material which shares with the alkali basalts similar trace element and isotopic compositions. This is corroborated by the rather similar isotopic compositions of the alkali basalts and trachytes. The correlations observed between incompatible elements (Nb, Th) and εNd and Pb isotopic initial ratios suggest that the Mamonia suite was derived from the mixing of a depleted mantle (DMM) and an enriched component of High µ (µ = 238U/204Pb, HIMU) type. Models using both Nd and Pb isotopic initial ratios suggest that the depleted tholeiites (Type 1) derived from a DMM source contaminated by an Enriched Mantle Type 2 component (EM2), and that the oceanic tholeiites (Type 2), alkali basalts (Type 3) and trachytes (Type 4) were derived from the mixing of the enriched mantle source of the depleted tholeiites with a HIMU component. None of the Mamonia volcanic rocks show evidence of crustal contamination. The Upper Triassic within-plate volcanism likely erupted in a small southerly Neotethyan basin, located north of the Eratosthenes seamount and likely floored by oceanic crust.

Keywords: Late Triassic volcanism, SW Cyprus, Pb–Nd, oceanic island basalts, Neotethys opening.

1. Introduction rocks stratigraphically connected with pelagic and/or reefal limestones. In the eastern Mediterranean area The Neotethyan ophiolitic suites which extend from (Antalya and Hatay in southern Turkey, Mamonia the eastern Mediterranean (Antalya, Troodos, Hatay, Complex from Cyprus; Fig. 1), this volcanism is Baer-Bassit)¨ up to the Persian Gulf (Samail nappes dated as Late Triassic (Marcoux, 1970; Dumont et al. in Oman: Bechennec´ et al. 1989, 1991) and the 1972; Robertson & Waldron, 1990) on the basis of Himalayas (Spontang ophiolites: Bassoullet et al. pelagic bivalves (Halobia), ammonites, corals and 1980a,b; Colchen, Mascle & Van Haver, 1986; microfaunas. In the Baer-Bassit¨ region (NW Syria), two Cannat & Mascle, 1990; Corﬁeld, Searle & Green, volcanic episodes are recorded, a well-known and wide- 1999; Maheo´ et al. 2000) are often tectonically spread Late Triassic event and an Early to Middle Jur- associated with Permian and Upper Triassic volcanic assic (Pliensbachian–Bajocian: Al-Riyami et al. 2000) event, considered previously as Late Jurassic to Early §Author for correspondence: [email protected] Cretaceous (Lapierre & Parrot, 1972; Parrot, 1974a,b; 2 H. LAPIERRE AND OTHERS

1980). The uppermost basaltic flows are associated and overlain by iron- and manganese-rich sediments (umbers) and radiolarian cherts of Late Cretaceous age (Perapedhi Formation). Along the northern Troodos margin, these formations are unconformably overlain by the Late Creta- ceous to Tertiary sedimentary cover. Along the south and southwestern Troodos margins, the Perapedhi sediments grade upwards into the tuffaceous sandstones and benthonitic clays of the Kannaviou Formation (Lapierre, 1968; Ealey & Knox, 1975; Robertson, 1977) which becomes tectonically overlain by a structural complex made of serpentinized harzburgite on which rest the Late Triassic to Late Cretaceous volcanic rocks and sediments of the Mamonia Complex. Tecto- nic slices of metamorphic rocks (Ayia Varvara Form- ation: Malpas, Calon & Squires, 1993) and Troodos Figure 1. Sketch map of the Neotethyan ophiolites and the ophiolitic rocks are imbricated within the Mamonia Permo-Triassic volcanic sequences (after Searle, 1983). tectonic pile (Ayia Varvara section, Fig. 2). A Late Cretaceous to Quaternary sedimentary sequence un- Delaune-Mayere` & Parrot, 1976; Rocci et al. 1980; conformably covers the Troodos ophiolite and the Delaune-Mayere,` 1984). The association of Late Mamonia Complex. Triassic submarine volcanic rocks with reefal and plat- The igneous and sedimentary rocks of the Mamonia form carbonates and/or deep-water carbonates and Complex are subdivided into two main tectono- radiolarites is systematically observed in the entire stratigraphic units: the Petra tou Romiou Formation Neotethyan ophiolitic belt (Fig. 1) and sets the (Lapierre, 1975) or Dhiarrizos Group (Swarbrick problem of the geodynamic setting of the Late Triassic & Robertson, 1980) and the Mamonia Formation magmatism. (Lapierre, 1975) or Ayios Photios Group (Swarbrick & We started a new petrochemical study of the Robertson, 1980; Fig. 3). The Petra tou Romiou Form- Mamonia volcanic rocks using both trace element and ation is the lower tectonic unit and consists of volcanic isotopic chemistry (Nd, Sr and Pb), in order to check the rocks of mafic to felsic composition associated with occurrence of a preserved Late Triassic oceanic crust Late Triassic pelagic and reefal sediments. The struc- in Cyprus as proposed by Malpas, Calon & Squires turally overlying Mamonia Formation is predominantly (1993). In this paper, we show that the Late Triassic formed of sedimentary rocks, which record the con- volcanic rocks of the Mamonia Complex represent temporaneous evolution of the basin from shallow to the remnants of intra-oceanic island volcanoes which deep water environments (Lapierre & Rocci, 1970; range from LREE-depleted tholeiitic olivine basalts to Lapierre, 1975). trachytes through oceanic island tholeiites and clino- On the basis of petrological and major element chem- pyroxene–plagioclase-rich alkali basalts. On the basis istry, earlier workers (Lapierre, 1975; Lapierre & of these data, we propose a reconstruction of the Ma- Rocci, 1976; Swarbrick & Robertson, 1980) have con- monia geodynamic setting during Late Triassic times sidered all the volcanic rocks of the Mamonia Complex and a model accounting for the tectonic imbrication as alkali basalts and their fractionated products. More of the Mamonia and Troodos ophiolitic complexes in recently, Malpas, Calon & Squires (1993) considered, Cyprus. on the basis of elemental chemistry, that more than 80 % of the Mamonia volcanic rocks are tholeiitic and exhibit N-MORB affinities. They concluded that 2. Geological features of the Troodos and Mamonia most of the Late Triassic basalts represent preserved complexes remnants of the Triassic oceanic crust, the main part of The Campanian to Maastrichtian Troodos ophiolitic which was subducted beneath the Troodos microplate. complex represents the basement of the island of According to Malpas, Calon & Squires (1993), the Cyprus, where it is widely exposed (Gass, 1980). It tholeiitic basalts of the Petra tou Romiou Forma- has experienced extensive Late Tertiary uplift of some tion are predominantly weakly pillowed lavas with 2000 m centred on a serpentinite diapir beneath the interpillow voids and fractures filled with calcilutite, Troodos summit. From base to top the Troodos ophi- manganiferous cherts and often covered by radiolarian olitic suite comprises the very classical ophiolite suc- cherts, shale and minor calcilutite. The aphyric and cession: (1) foliated harzburgite, (2) cumulate plutonic highly porphyritic alkali basalts are associated with the rocks, (3) isotropic gabbros and plagiogranites, same range of sedimentary rocks. The aphyric pillow (4) sheeted dyke complex and (5) basaltic flows (Gass, basalts have abundant calcite- or zeolite-filled vesicles The Mamonia Complex 3

Figure 2. (a) Simpliﬁed geological map of Cyprus showing the location of the erosional windows of the Mamonia complex (based on the geological maps of Lapierre, 1975; Malpas, Xenophontos & Williams, 1992; Malpas, Calon & Squires, 1993). (b, c) Structural cross-sections along section lines in the Akamas peninsula (b) and Ayia Varvara (c) windows based on the geological maps of Lapierre (1975) and our own observations (this paper). The locations of the sections are shown in (a). 4 H. LAPIERRE AND OTHERS

and a continental microplate located south of Cyprus. According to Malpas, Calon & Squires (1993), the continental margin rocks of the Mamonia Complex were delaminated from their basement upon arrival at a N- dipping subduction zone and emplaced onto the fore- arc region of the Troodos microplate. For Clube & Robertson (1986), McLeod (1990), Swarbrick (1993) and McLeod & Murton (1995), the emplacement of the Mamonia Complex and Troodos tectonic imbrication took place along transcurrent faults which affected the Troodos southwestern margin, the Limassol Forest and Akamas Peninsula, or along a fossil oceanic transform fault (E–W Arakapas–Athrakos Fault). More recently, Bailey, Holdsworth & Swarbrick (2000) have distinguished in the Mamonia Complex Suture three main tectonic events of Late Cretaceous age: (1) a high temperature (600 ◦C) transform-related, dextral Figure 3. Simplified stratigraphic terminology of the Mesozoic strike-slip and localized metamorphism (Ayia Varvara rocks from Cyprus (after Lapierre, 1975; Swarbrick & Formation, 90–83 Ma), (2) retrograde hydration during Robertson, 1980; Malpas, Calon & Squires, 1993). dextral transtension associated with a rotation of the Cyprus microplate and the shallow level emplacement and rest upon the tholeiitic basalts. Clinopyroxene- of serpentinites (83–73 Ma), and finally, (3) a regional phyric ankaramites, trachytes and phonolites are poorly contractional reactivation at low temperature which exposed and represent less than 5 % of the Mamonia ended by the latest Maastrichtian (65 Ma). This de- Complex volcanics. formation history is consistent with a model postulating The Mamonia Formation, the base of which is un- that a Troodos microplate impinged on the Mamonia known, consists of sandstones with fossil plant remains, Complex during westerly- to southwesterly-directed Halobia pelagic limestones stratigraphically overlain plate motion, contractionally reactivating the weak by a thick pile of radiolarian cherts, black spongolites suture zone. interbedded with red and/or green clays, mudstones, siltstones and micritic limestones. Locally, bituminous 3. Analytical procedures shales (near Ayios Photios village) or green dark sandstones (Akamas peninsula) are interbedded within the Mineral analyses were carried out on the Cameca radiolarian cherts. The age of the Mamonia Formation SX100 electron microprobe fitted with five wavelength ranges from Late Triassic to Late Cretaceous (Bragin, spectrometers at the ‘Service commun microsonde’, Bragina & Krylov, 2000). Locally, alkali dolerite dykes University of Montpellier II. The standard working and sills intrude the lowermost sandstones. conditions were 20 kv and 10 nA, with a beam size The Mamonia Complex is stratigraphically overlain of 1 µm and integrated counting times of 20–30 s. The successively by an olistostrome unit composed of accuracy of major element determinations is better than metre- to kilometre-size blocks of the underlying ± 1 % of the total value. rocks (Mamonia volcanics and sediments, Ayia Varvara Major elements and compatible trace element analy- metamorphic rocks, silicified serpentinites: Malpas, ses by ICP-Optical Emission Spectroscopy were done Xenophontos & Williams, 1992) set into a grey to pink at the ‘Centre de Recherche Petrographiques´ et argillaceous matrix (Moni Melange´ and/or Kathikas Geochimiques’´ (CRPG) in Nancy, on whole rocks Melange:´ Swarbrick & Naylor, 1980) and by the gently powdered in an agate mill. Other trace elements, in- deformed Late Cretaceous to Early Tertiary Lefkara cluding the REE, were analysed by ICP-MS at the Uni- Formation (Fig. 3). versity Joseph Fourier in Grenoble, after acid dissolu- The tectonic emplacement of the Mamonia Complex tion of 100 mg sample, using the procedures of Barrat, onto the Troodos Complex occurred after the depos- Keller & Amosse´ (1996). Limits of detection are: REE ition of the Late Cretaceous Kannaviou Formation and Y = 0.003 ppm, U, Pb and Th = 0.005 ppm, Hf and and before that of the Late Cretaceous–Early Tertiary Nb = 0.01 ppm, Ta = 0.03 ppm, and Zr = 0.04 ppm. Lefkara Formation, that is, during Maastrichtian The standards used for the analyses were JB2, Bhvo-2, time (Lapierre, 1975; Robertson & Woodcock, 1982; Bir-1 and UBn1. Analytical errors are 1–3 % for major Swarbrick, 1993). The nature of the collision of these elements and less than 3 % for trace elements. two complexes remains a matter of debate. For Murton Sr and Nd isotopic ratios were measured at the Labor- (1990) and Malpas, Calon & Squires (1993), the atoire de Geochimie´ isotopique de l’Universite´ Paul emplacement of the Mamonia nappes onto the Troodos Sabatier de Toulouse on a Finnigan MAT261 mul- Complex is due to a frontal collision between Troodos ticollector mass spectrometer using the analytical The Mamonia Complex 5 procedures described by Lapierre et al. (1997). ism, we have plotted La, Pb and Rb against Th con- Results on La Jolla Nd standard yielded 143Nd/144Nd = sidered as immobile during post-magmatic processes 0.511850 ± 0.000017 (2σ external reproducibility, n = (Fig. 4). The majority of the Mamonia volcanics (with 12). Results on NBS 987 Sr standard yielded an aver- the exception of trachytes) exhibit a linear trend in the age of 87Sr/86Sr = 0.710250 ± 0.000030 (2σ external La and Pb v. Th plots (Fig. 4a, b), suggesting that these reproducibility, n = 11). 87Sr/86Sr and 143Nd/144Nd were elements have not been extensively affected during the normalized for mass fractionation relative to 86Sr/ low-grade metamorphism experienced by the Mamonia 88Sr = 0.1194 and 146Nd/144Nd = 0.7219, respectively. rocks. In particular, in the Pb v.Th diagram (Fig. 4b) the 143 144 εNdi calculated with actual ( Nd/ Nd)CHUR = samples define a line with a correlation factor of 0.76, 147 144 0.512638 and ( Sm/ Nd)CHUR = 0.1967. εSri cal- which increases to 0.96 when removing the trachytes 87 86 culated with actual ( Sr/ Sr)CHUR = 0.70450 and from the calculation. This feature suggests that Pb 87 86 ( Rb/ Sr)CHUR = 0.084 (McCulloch & Wasserburg, remains almost immobile in all the samples studied 1978). except in the trachytes. In contrast, the scattering of For lead separation, powdered samples were weighed Mamonia samples observed in the Rb v. Th diagram is to obtain approximately 200 ng of lead. With a view related to Rb mobility during low-grade metamorphism to remove possible effects of submarine alteration, (Fig. 4c). samples were intensively leached with a HF + 6N HCl Because this low-grade metamorphism modified the mixture for 30 minutes at 65 ◦C before acid dissolution bulk major element chemistry, the various types among and lead chemical separation. Such leaching experi- the Mamonia volcanic rocks have been discriminated ments have been previously efficiently used to remove using Ti and immobile trace elements Zr, Nb and Y secondary alteration effects (e.g. Abouchami, Galer (Fig. 5a). Cr spinel–olivine basalts plot at the bound- & Hofmann, 2000). Lead isotopes were analysed on ary of fields 3 and 5. Intersertal plagioclase and clino- a VG Plasma 54 multi-collector inductively coupled pyroxene basalts cluster in the alkali basalt field, but the plasma-mass spectrometer (MC-ICP-MS) at the ‘Ecole porphyritic volcanic rocks show an evolution towards Normale Superieure´ de Lyon’. Lead isotope composi- more evolved facies (hawaiites and mugearites). One tions were measured using the Tl normalization method basaltic sample with intersertal texture (CY01-29) plots described by White, Albarede` & Telouk (2000). For near the limit between alkali and sub-alkali basalts Pb isotope analysis, samples were bracketed between (Fig. 5a). Four groups have been therefore distin- NIST 981 standards and calculated with respect to the guished based on the texture, mineralogy and trace value reported for this standard by Todt et al. (1996). element chemistry: This technique yields internal precision of ∼ 50 ppm Type 1 – depleted tholeiites represented by Cr- (2σ ) and an external reproducibility of ∼ 150 ppm (2σ spinel (CY01-49) and olivine-bearing basalts (CY01- for 206Pb/204Pb ratios, n = 20). 08, CY01-10); All the isotopic data have been corrected for in situ Type 2 – oceanic island tholeiite represented by decay using an age of 210 Ma (Late Triassic) on the intersertal basalt CY01-29; basis of the Norian–Carnian fauna found in the pelagic Type 3 – alkali basalts including two intersertal lavas limestones. (CY01-05, CY01-06) and the olivine-, plagioclase- and clinopyroxene-phyric basalts and hawaiites (CY01-02, CY01-19, CY01-25, CY01-28, CY01-43, CY01-47); 4. Petrographic and chemical data Type 4 – trachytes (CY01-03, CY01-18A, CY01-23, CY01-24). 4.a. Sample selection and alteration Fifteen samples were selected for petrological and 4.b. Major and trace elements geochemical investigations, based on petrographic 4.b.1. Type 1 – depleted tholeiites type, the overall freshness of the volcanic rocks, and the type of sediments they are associated with. The location These pillowed basalts are associated with or strati- of analysed samples is shown in Figure 2a. graphically overlain by red radiolarian cherts and pink Whole rock major, trace element, and Nd, Sr and Pb pelagic limestones. They show quenched margins and isotopic chemistry of the Mamonia volcanic rocks are variolitic textures. They consist of skeletal (< 1 mm) given in Tables 1 and 2. The high levels of loss of igni- olivine phenocrysts pseudomorphed into celadonite, tion (LOI) values are due to the abundance of calcite- calcite or chalcedony, embedded in a fine-grained or zeolite-filled vesicles. Because of the low-grade matrix, which contains plagioclase and clinopyroxene. metamorphism which affects the Mamonia Complex Olivine often includes euhedral Ti-free brown spinels, volcanic rocks, Large Ion Lithophile Elements (LILE) with rather high Cr no. (Cr/Cr+Al) and Mg no. known to be sensitive to alteration and metamorphism (Mg/Mg+Fe). are not considered to be representative of the primary The Cr-spinel and olivine basalts have the highest composition of these rocks. To test the behaviour of Ni contents and the lowest abundances in Ti (Fig. 5b), some incompatible trace elements during metamorph- incompatible elements (Zr, Hf, Nb, Ta, Th, Y) and 6 H. LAPIERRE AND OTHERS 47 91 41 0 78 46 97 11 61 37 32 91 29 77 82 13 07 44 30 24 47 87 0 00 07 05 29 14 43 98 49 70 39 35 05 22 12 74 85 25 ...... 70 99 86 99 99 275 06 00 3 34 0 89 22 77 390 15 10 70 30 08 98 83 2 44 26 58 3 68 20 58 171 16 0 91 10 35 198 51 1060 31 1 48 80 05 55 4 19 0 57 110 68 6 51 11 69 1 1792 68 9 0 81 45 65 3 21 0 00 0 89 29 32 10 26 20 95 5 32 4 ...... 30 97 95 99 08 207 03 26 3 31 1 96 21 46 255 36 10 22 19 68 248 18 2 92 17 08 6 96 12 47 100 41 0 61 7 87 130 65 984 22 1 68 73 08 99 3 08 0 66 101 28 2 20 4 14 4 5061 67 12 02 02 28 69 4 49 0 06 0 89 19 76 9 87 17 89 1 58 4 ...... 61 89 86 99 91 199 00 17 2 96 0 02 18 52 161 19 8 71 13 98 475 88 5 81 12 43 4 09 11 16 66 18 0 07 12 21 82 94 891 21 1 29 66 07 72 2 07 0 65 86 40 1 85 7 94 4 7014 66 10 02 59 18 76 4 52 0 09 0 13 15 96 7 96 13 10 2 80 5 ...... 22 37 95 99 25 193 02 47 2 91 2 33 20 67 197 97 8 97 15 27 662 34 2 34 13 13 11 28 10 78 84 32 0 28 2 53 99 04 907 49 1 77 58 02 49 2 31 0 40 78 12 6 62 5 57 4 4052 60 16 01 17 23 74 4 39 0 81 0 43 13 44 7 71 12 37 3 70 3 ...... 999 00 31 1 79 44 83 1 81 7 26 125 66 3 06 144 93 11 05 799 40 2 96 5 12 10 29 0 80 4 445 4 44 0 01 41 1 78 64 15 0 28 72 07 412 80 642 41 7 59 40 26 5 070 85 4 3290 2 11 92 0 27 8 7992 51 18 04 3 32 7 87 17 45 4 01 2 ...... 06 3 89 99 02 86 1 58 33 53 1 59 6 75 99 40 3 28 125 47 10 16 3 76 9 33 670 89 10 23 0 74 2 14 5 29 0 05 89 1 23 57 69 0 34 64 51 345 27 314 63 14 72 39 01 13 097 80 4 0688 2 8 41 0 86 6 8305 48 14 69 7 98 14 92 3 18 4 ...... 24 4 68 2 88 99 046 18 0 52 19 06 5 05 4 33 53 20 2 06 64 31 6 42 1 26 8 21 5 30 0 77 1 08 3 37 0 43 362 067 19 0 32 31 69 0 67 30 69 209 93 317 92 44 70 24 60 9 0 522 41 5 0571 3 8 67 0 37 3 6636 48 18 45 7 83 1 13 1 ...... 24 6 34 2 07 2 999 01 91 1 88 29 93 2 54 6 05 67 74 3 29 92 47 9 07 1 07 11 34 8 15 0 82 1 13 4 37 0 46 304 06 03 1 76 46 20 0 85 43 84 281 04 522 30 14 59 33 72 8 0 189 71 3 7183 3 8 31 0 55 4 1039 47 13 99 11 14 2 ...... 16 5 17 2 33 2 02 99 67 7 066 69 0 59 16 10 5 65 5 00 53 37 2 23 66 66 6 37 1 81 5 07 6 16 0 28 1 20 3 31 0 76 385 0 165 83 1 86 31 10 0 58 32 52 264 27 375 18 24 45 29 96 6 0 191 70 5 6900 1 8 20 0 47 4 1296 51 18 12 1 ...... 37 4 30 2 32 24 34 1 82 100 77 3 060 72 0 98 1 20 7 70 2 82 21 54 2 86 27 81 3 42 0 46 5 30 4 17 0 99 1 29 1 32 0 53 62 062 88 0 86 15 96 0 56 12 93 112 00 716 09 41 08 9 0 316 00 4 7534 1 10 21 0 57 1 7313 49 16 37 0 ...... 73 4 03 110 38 2 43 25 39 1 87 99 21 3 067 03 0 37 25 13 5 84 2 28 20 92 2 40 29 59 3 03 0 50 9 23 4 36 0 96 0 55 1 34 0 71 63 044 09 0 49 15 03 0 02 13 14 215 04 46 22 13 0 267 23 3 6629 1 10 41 0 90 1 9223 47 16 96 2 ...... 95 5 82 223 44 2 45 32 68 3 44 2 85 99 75 9 027 96 1 13 16 42 6 02 4 47 61 72 2 41 74 11 7 27 1 09 5 22 7 21 0 44 1 57 3 53 0 57 475 032 31 1 77 37 15 0 74 36 33 441 58 41 11 10 0 398 45 3 8765 3 13 18 0 0687 44 15 19 1 ...... 96 5 17 238 74 117 87 3 47 37 12 0 66 1 84 99 84 2 055 45 0 53 2 15 6 22 3 30 9 99 3 52 18 67 4 06 0 88 5 40 5 14 0 16 0 08 0 28 0 46 179 095 66 1 76 13 03 0 76 7 31 46 51 1 0 375 49 3 7402 1 13 06 0 3054 49 13 )...... 3 O 2 26 47 38 2 56 97 11 45 18 1 97 19 12 0 24 0 83 99 62 0 0 168 83 0 80 0 50 4 38 1 74 1 38 1 78 4 22 1 17 0 19 5 57 2 27 0 37 0 11 0 47 0 35 16 0 467 14 0 35 4 33 0 78 1 38 16 0 207 52 3 5150 0 9 17 0 4710 51 14 56 nd 0 ...... 59 51 16 5 51 96 47 3 43 254 09 34 18 0 95 1 79 99 31 1 0 228 65 0 17 10 38 4 85 2 51 1 71 3 30 8 50 3 07 0 11 10 49 4 17 0 40 0 16 0 37 0 69 58 0 458 92 1 06 9 09 0 56 2 38 14 0 342 92 4 1689 1 12 13 0 5590 45 16 49 0 ...... 1 9 0 47 15 CY01-08 CY01-10 CY01-49 CY01-29 CY01-02 CY01-05 CY01-06 CY01-19 CY01-25 CY01-28 CY01-43 CY01-47 CY01-03 CY01-18 CY01-23 CY01-24 is total iron presented as Fe ∗ ∗ 3 3 3 O 5 2 2 O3 O O 2 2 O0 2 2 O 2 2 Co 45 Dy 4 CaO 13 Zr 71 Yb 2 Sr 145 V 277 Y27 Th 0 Eu 0 Total 99 Pr 1 Ni 240 Tb 0 Rb 4 MgO 7 Hf 1 Nb 2 Er 2 Ce 7 U0 Sm 2 K Al LOI 8 Gd 3 MnO 0 Pb 0 Na P Ta 0 Lu 0 Ba 26 Cr 610 Ho 0 Nd 7 Cs 0 La 2 TiO Fe Table 1 Major and trace element composition (in wt %, and ppm, respectively) of the Mamonia volcanic rocks SiO (Fe Sample (Type 1) (Type 1) (Type 1) (Type 2) (Type 3) (Type 3) (Type 3) (Type 3) (Type 3) (Type 3) (Type 3) (Type 3) (Type 4) (Type 4) (Type 4) (Type 4) The Mamonia Complex 7 9 6 17 16 ± ± ± ± 512726 824443 107345 512578 512758 703867 59938 813684 11 97 09 68 47 95 72 72 55 14 123245 1301933 703477 512589 02 10 69 41 42 75 26 95 31 29 ...... 60 10 0 10 0 ± ± ± 512715 11475 0 512557 0 74 56 196 956818 20 15 39 96 18 787225 20 15 41 18 0 ...... 512798 704389 1394371 0 006461 0 704375126064 0 0 04 175 355802 20 15 39 986283 21 15 41 99 39 66 4 14 0 ...... 90 90 10 0 ± ± ± 512847 705245 1452693 0 1452693 0 7042015126474 0 0 03 77 46 4 5662 19 17 15 39 4967 19 31 15 39 12 18 21 0 ...... 512675 120226 0 51251 0 77 3 977078 19 15 39 39 24 74 196 887469 20 15 41 20 0 ...... 10 0 80 10 0 ± ± ± 512683 0 706854 112878 0 866602 3 701275512527 0 0 13 2 0266 19 70 15 39 86 27 38 86 2782 20 57 15 40 71 0 512739 703453 1225208 0 107313 0 7031335125706 0 0 98 108 96 5 427072 19 15 39 597619 20 15 40 43 28 26 0 ...... 21 0 10 0 11 0 08 0 ± ± ± ± 512705 703586 111755 0 198957 1 702991512551 0 0 59 3 556415 19 15 38 33 97 2 461 757057 22 15 43 27 0 513012 704224 180638 0 0258122 0 704146512764 0 0 73 138 73 3 556290 20 15 39 916901 21 15 41 94 35 30 0 ...... 60 80 12 0 08 0 ± ± ± ± 512697 705698 36 3 114395 0 3104769 0 704770351254 0 0 0068 19 39 15 39 42 36 85 135 7782 20 06 15 40 61 0 ...... 512937 705429 212126 0 015777 0 7053815512645 0 0 42 7 715632 19 15 38 445982 20 15 40 18 40 78 105 16 0 ...... 10 0 19 0 11 0 90 ± ± ± ± 512739 705021 89 3 513013 01 5 705978 208133 0 125158 0 12276 0 17846 0 705611512727 0 0 704488512567 0 0 3350 18 23 15 38 2755 19 46 15 38 4021 22 0 82 47 ...... 15 0 20 14 0 14 0 ± ± ± ± 43 3 966930 20 15 39 42 83 76 158 121508 0 777812 22 15 41 512864 703409 1632695 0 702922512697 0 0 40 0 ...... 48 7 6453 18 27 15 38 9855 19 59 15 38 4808 28 0 16 21 214619 0 513046 0833005 0 705644512751 0 0 705892 CY01-08 CY01-10 CY01-49 CY01-29 CY01-02 CY01-05 CY01-06 CY01-19 CY01-25 CY01-28 CY01-43 CY01-47 CY01-03 CY01-18A CY01-23 CY01-24 ...... 0 0 . 0 0 i i i i Nd) Nd) Pb)iPb)i 18 Pb)i 15 38 Pb)iPb)i 19 Pb)i 15 39 Nd 0 Nd 0 Nd 0 Nd 0 Pb 30 Pb 172 Continud. PbPb 21 Pb 15 41 PbPb 18 Pb 15 38 PbPb 10 0 PbPb 54 0 Sr) Sr) 144 144 Sr 0 Sr 0 204 204 204 204 204 204 144 144 Sr 0 Sr 0 144 144 204 204 204 204 204 204 204 204 86 86 86 86 204 204 204 204 86 86 Nd/ Pb/ Pb/ Pb/ Nd/ Pb/ Pb/ Pb/ Sr/ Sr/ Nd/ Sm/ Pb/ U/ Pb/ U/ Pb/ Th/ Nd/ Sm/ Pb/ U/ Pb/ U/ Pb/ Th/ Sr/ Rb/ Sr/ Rb/ Nd 6 Nd 7 87 143 206 207 208 87 143 206 207 208 ( ε ( ( ( ( ( ( ( ε ( ( Sample (Type 1) (Type 1) (Type 1) (Type 2) (Type 3) (Type 3) (Type 3) (Type 3) Table 2 Sr, Nd and Pb isotopic composition of the Mamonia volcanic rocks 87 87 143 147 206 238 207 235 208 232 Sample (Type 3) (Type 3) (Type 3) (Type 3) (Type 4) (Type 4) (Type 4) (Type 4) Table 2 87 87 143 147 206 238 207 235 208 232 8 H. LAPIERRE AND OTHERS

Rare Earth Elements (REE) (Fig. 6a, b). Olivine basalts are characterized by depleted Light REE (LREE) patterns (0.63 < (La/Yb)N < 0.74). The primitive mantle- normalized (Sun & McDonough, 1989) multi-element plots of these olivine basalts show Th and Pb negative anomalies and no enrichment or depletion in Nb and Ta relative to LREE (Fig. 6b). Such features are char- acteristic of N-MORB. These basalts have then been classiﬁed as depleted tholeiites or Type 1 tholeiites.

4.b.2. Type 2 – oceanic island tholeiite (OIT) Sample CY01-29 was collected in a pillowed ﬂow associated with pink calcilutite. It consists of andesine (An32–49) laths embedded by augite (Wo35–44En36–46Fs13–23) and late crystallized titanomagnetite. This basalt shows a ﬂat to slightly enriched REE pattern ((La/Yb)N = 1.6) (Fig. 6a). Its primitive mantle-normalized multi-element plot (Fig. 6b) displays features of transitional (T)-MORB or oceanic island tholeiite (OIT).

4.b.3. Type 3 – alkali basalts Alkali intersertal basalts are mostly found as pillows and hyaloclastites capped by pink calcilutite (CY01- 05), which also fill interpillow voids and fractures. Less often, they occur as massive flows associated with white reefal limestones (CY01-06). They consist of plagioclase laths embedded by clinopyroxene and late crystallized titanomagnetite. Plagioclase is often replaced by albite or zeolites. When preserved, it shows a labradorite (An50–55) composition. The clinopyroxene is a Mg-rich augite (Wo35–44En37–46Fs13–24) which exhibits Fe-enrichment both from core to rim within a single crystal and from phenocrysts to microcrysts. The sequence of crystallization of these two basalts (olivine–plagioclase–clinopyroxene–magnetite) is that of a tholeiite, but their trace element chemistry is close to that of mildly alkaline rocks. The other alkali basalts are porphyritic, with abundant centimetre-sized plagioclase phenocrysts, with the exception of samples CY01-47 and CY01-43 which are aphyric. CY01-43 was sampled in a dyke intruding the pillowed flows. The porphyritic volcanic rocks commonly contain calcite-, celadonite-, prehnite- and/or zeolite-filled vesicles. Their groundmass is composed of abundant plagioclase microlites, clinopyroxene microphenocrysts, acicular ilmenite and titanomagnetite. Frequently, TiO2-rich oxides are rimmed by late- magmatic biotite. Preserved (anorthoclase: Ab76Or23) or altered (adularia: Ab1–2Or98–99) alkali feldspar microlites may occur in the groundmass. When present, olivine is systematically replaced by serpentine, smectite or less frequently by anthophyllite or calcite. Plagioclase phenocrysts are zoned with bytownite Figure 4. (a) La (ppm) v. Th (ppm), (b) Pb (ppm) v. Th (ppm), (c) Rb (ppm) v. Th (ppm) plots for the Mamonia volcanic rocks. (An82–85) or labradorite (An54–64) cores and labradorite The correlation factor calculated for the Pb v. Th regression line (An52–62) or andesine (An30–49) rims. Clinopyroxene (b) does not integrate the trachytic samples. phenocrysts are diopside (Wo45–47En36–41Fs9–18) The Mamonia Complex 9

Figure 5. (a) Zr/Ti v. Nb/Y and (b) V (ppm) v. Ti/1000 plots of the Mamonia volcanic rocks. Fields are after Winchester & Floyd (1977) and Shervais (1982).

Figure 6. Chondrite-normalized Rare Earth Element patterns and primitive mantle-normalized multi-element plots of: (a, b) the Mamonia tholeiites; (c, d) the Mamonia alkali basalts; (e, f) the Mamonia trachytes. The grey ﬁelds indicated in (c) and (e) correspond to the Kerguelen alkali basalts and trachytes domain and are shown for comparison (data are from Kieffer, Arndt & Weiss, 2002). Normalization values from Sun & McDonough (1989).

evolving towards pink TiO2-rich (1.6 to 3.7 %) augite enriched LREE patterns (4.2 < (La/Yb)N < 15.16; (Wo42–45En37–34Fs14–19). CY01-47 and CY01-4 are Fig. 6c) and are enriched in incompatible elements. characterized by a seriate texture marked by fluidal Their primitive-mantle normalized multi-element plots plagioclase laths and/or microlites. The occurrence of are typical of alkalic mafic lavas with positive Th, Nb, late magmatic biotite suggests the presence of water Ta and Ti anomalies (Fig. 6d). Samples CY01-47 and in this magma. CY01-43 differ from the other rocks by their negative Type 3 basalts show high TiO2 contents (Fig. 5b, Ti anomaly, which may be attributed to separation Table 1). The Cr contents of the porphyritic basalts are of Ti-rich magnetite; this suggests they represent the significantly higher than those of the volcanic rocks most fractionated rocks. Samples CY01-05 and CY01- with seriate and intersertal textures. Type3 basalts have 06 differ by their lower (La/Yb)N ratios and abundances 10 H. LAPIERRE AND OTHERS of most incompatible elements. They display mildly alkaline features and could therefore represent a transition between the ocean island tholeiite and the alkali basalts.

4.b.4. Type 4 – trachytes The mode of occurrence of the trachytes (CY 01- 03, 01-18A, 01-23, 01-24) is difficult to determine because most of our samples come from loose blocks of the Moni and/or Kathikas olistostromes, or from slivers caught within the thrust faults. However, when mapping the Paphos-Polis area in the early seventies, one of us (Lapierre, 1975) observed that the trachytes formed either small columnar-jointed flows resting on the pillows or dykes cutting the extrusive rocks. Light green or yellow in colour, the trachytes are alkali feldspar-phyric and seriate textured (CY01-23 and CY01-24) or aphyric and flow-banded with abundant flattened vesicles (CY01-03). When preserved, alkali feldspar has an anorthoclase (Ab60–64Or35–39) or san- idine composition. Na-rich clinopyroxene replaced by chlorite occurs in most rocks. Trachytes are the most fractionated rocks of the Mamonia Complex as shown by their very low contents in compatible elements, Cr, Ni and V (Table 1). They are very LREE-enriched with (La/Yb)N ratio ranging between 9 and 14. Their REE patterns (about 1000 times the chondritic abundances; Fig. 6e) exhibit a ∗ ≥ ≥ 206 204 207 204 marked negative Eu anomaly (0.96 Eu/Eu 0.32), Figure 7. (a) εNdi v. ( Pb/ Pb)i and (b) ( Pb/ Pb)i v. 206 204 indicative of significant plagioclase removal. Their ( Pb/ Pb)i correlation diagrams showing that the Mamonia primitive mantle-normalized (Sun & McDonough, Upper Triassic volcanics were derived from the melting of 1989) spidergrams show Pb, Sr, P and Ti negative enriched OIB type mantle sources. Mantle reservoirs are from anomalies, which can be attributed to plagioclase, Zindler & Hart (1986): Depleted MORB Mantle (DMM), apatite and magnetite removal (Fig. 6f). Enriched Mantle 1 (EM1), Enriched Mantle 2 (EM2), High µ=238U/204Pb (HIMU). The bulk silicate Earth value (BSE) is from Allegre,Lewin&Dupr` e´ (1988). NHRL = Northern = 4.c. Isotopes Hemisphere Reference Line (Th/U 4.0) has been defined by Zindler & Hart (1986). 206 204 Reported in the εNdi v. Pb/ Pbi diagram (Fig. 7a), Type 1 tholeiites differ from N-MORB by lower εNdi 206 204 values (+5.4 <εNdi < +7.5). They show the least confirmed by the Pb/ Pb ratio, which is the highest Pb radiogenic isotopic composition and the higher of all the Mamonia volcanic rocks (Fig. 7b). 87 86 Sr/ Sri ratios of the Mamonia volcanics (Table 2). The Type 4 rocks share with the alkali basalts 207 204 206 204 In the Pb/ Pbi v. Pb/ Pbi diagram (Fig. 7b), similar εNdi values and isotopic Pb ratios. One trachyte they plot in the MORB-field and along the North (sample CY01-03) differs from the others by its 206 204 Hemisphere Reference Line (NHRL: Zindler & Hart, significantly lower Pb/ Pbi (Table 2; Fig. 7a, b). 1986). In summary, the Late Triassic Mamonia volcanism The εNdi value of Type 2 tholeiite (+7.7) (Table 2; ranges from depleted olivine-tholeiites to trachytes Fig. 7a) is the highest of the Mamonia volcanic suite through intersertal and plagioclase-clinopyroxene- and in the same range as those of the depleted tholeiites. phyric alkali basalts and oceanic island tholeiites. In contrast to Type 1 tholeiites, the initial Pb isotopic Depleted olivine basalts are associated with radiolarian ratios of sample CY01-29 are significantly higher and cherts while most pelagic limestones and cherts are similar to those of some alkali basalts (Fig. 7a, b and found interbedded with alkali basalts. Low-grade hy- 87 86 next Section). The Sr/ Sri of this sample is slightly drothermal alteration, characterized by the presence of lower than those of the depleted tholeiites (Table 2). albite ± adularia ± celadonite ± prehnite ± smectites The εNdi of Type3 span a large range of values (from ± zeolites ± calcite ± chalcedony, variably affects +3.4 to +6.4) and fall in the field of OIB (Fig. 7a). all the rock types. The whole Mamonia suite displays The enriched character of the Type 3 mantle source is geochemical features of within-plate magmatism. The Mamonia Complex 11

Figure 8. Incompatible trace element plots showing the geochemical relations between the four types of Mamonia volcanic rocks: (a) La (ppm) v. Nb (ppm), (b) La (ppm) v. Th (ppm), (c) Nb (ppm) v. Th (ppm), (d) La/YbN v. La (ppm), (e) Zr (ppm) v. La (ppm).

5. Discussion assuming a homogeneous mantle source. However, in the Zr–La diagram only one trachyte plots on the 5.a. Geochemical relationships between the four volcanic tholeiite–basalt trend (line 1, slope Zr/La = 5.2). On the types same diagram, the four trachytes alone define another Mamonia mafic volcanic rocks exhibit positive correl- trend (line 2, slope of 1.5). Similarly, in the La/Yb v. La ation trends in the La–Nb, La–Th, Nb–Th and Zr–La diagram (Fig. 8d), the Mamonia volcanic rocks clearly diagrams (Fig. 8a–c, e). The trachytes do not fall within exhibit two different trends: a steep positive line (Trend these trends, except sample CY01-24. This evolution 1) defined by samples of Type 1, 2 and 3 (slope equal from the depleted tholeiites towards the most enriched to 0.3); and a second trend (Trend 2 with a slope equal alkali basalts and one trachyte may be attributed to to 0.05) cross-cutting Trend 1 at the level of the less- a temporal decrease in the degree of partial melting, enriched alkaline basalt (CY01-5). The presence of 12 H. LAPIERRE AND OTHERS two distinctive trends suggests that the Mamonia mafic and felsic rocks are not linked together by crystal fractionation. This is a common feature observed in recent within-plate oceanic island volcanoes (Nuku Hiva island, Marquesas, French Polynesia: Legendre et al. 2005). The trachytes display patterns with highly fractionated MREE and Ti, Sr and Pb negative anomalies. These features are consistent with strong fractionation of amphibole, Fe–Ti oxides, apatite and plagioclase. Indeed, these minerals incorporate Ti (amphibole and/or Fe–Ti oxides) and LREE, Sr and Pb (apatite and plagioclase). The trachytes could derive from the partial melting at depth of mafic material which shares with the most differentiated alkali basalts similar Nd and Pb isotopic compositions (Fig. 7a, b). In contrast, the tholeiites and less-evolved alkali volcanic rocks display more varied geochemical features and were probably derived from heterogeneous enriched mantle sources.

5.b. Nature of the mantle sources Sr initial isotopic ratios may not be used to characterize the magmatic signature of the studied volcanic rocks, considering the mobility of Rb during the submarine alteration processes (Fig. 4c). The Pb initial isotopic ratios have been tentatively used to characterize the composition of the mantle sources, considering that (1) Pb and Th (and to a lesser extent, U) contents have not been significantly modified by the submarine alteration (see the correlation between Pb and Th in Fig. 4b) and (2) the whole-rock powders have been thoroughly leached before Pb separation to remove any trace of superficial alteration (refer to Section 3). 207 204 206 204 In the εNdi and ( Pb/ Pb)i v. ( Pb/ Pb)i diagrams (Fig. 7a, b), the Mamonia volcanic rocks exhibit a trend extending from the depleted MORB to the HIMU field, except trachyte (CY01-18), which plots 207 204 206 204 in the ( Pb/ Pb)i v. ( Pb/ Pb)i diagram at the boundary between the EMII and OIB fields. This observation suggests that the Mamonia volcanic suite derived from the mixing between a depleted MORB source and a HIMU enriched source. None of the εNdi values of the Mamonia volcanic rocks falls within the MORB field, not even the two tholeiitic basalts (CY01- 29 and CY01-08) which display the highest εNdi values (+7.7 and +7.4, respectively; Table 2). Similarly, the curvilinear trend displayed by the Mamonia volcanic Figure 9. (a) εNd v. Nb (ppm), (b) εNd v. Th (ppm), (c) εNd v. ε i i i suite in the Ndi v. Nb and (La/Yb)N plots (Fig. 9a, c) (La/Yb)N correlation diagrams showing that the Upper Triassic suggests that this suite was derived from the mixing of a Mamonia volcanic rocks derived from the melting of enriched depleted source and a Nb- and Th-enriched component. OIB type mantle sources. This enriched component could be a HIMU mantle type. Figure 10a and b illustrate a model that likely ex- mixing line (A) between the DMM and HIMU fields. plains the variations of the Mamonia Nd and Pb initial The depleted tholeiites (Type 1) are less contaminated isotopic ratios. In the 207Pb/204Pb v. 206Pb/204Pb diagram by the HIMU component while most of the alkali (Fig. 10b), the studied volcanic rocks (with the excep- basalts and hawaiites and three out of four trachytes tion of the trachytic sample CY 01-24) plot along the contain a higher imprint of a HIMU component. The The Mamonia Complex 13

5.c. Temporal evolution of the Mamonia volcanism The Upper Triassic Mamonia volcanic rocks represent the remnants of a rifted volcanic passive margin or within-plate oceanic volcanoes, located north of the African–Arabian rifted margin. They likely belong to an intra-oceanic setting because (1) they are associated with radiolarian cherts or pelagic to reefal limestones deposited in the basin, (2) no volcanic rocks are interbedded (with the exception of few alkaline dykes) within the sediments (sandstones with fossil plant remains and Halobia-bearing limestones of the Mamonia Formation or Ayios Photios Group, Fig. 3) deposited on the rifted northern African margin, and (3) the incompatible trace element ratios do not show the presence of any continental crust contamination (with the exception of recycled continental derived sediments). The nature of the sediments, associated with the volcanic rocks, allows us to constrain the environment and depth of the volcanic eruptions. Moreover, in the 143 144 206 204 207 206 Figure 10. (a) Nd/ Nd v. Pb/ Pb and (b) Pb/ Pb v. Mamonia Complex, in spite of the tectonic disturb- 206Pb/204Pb variation diagrams for the Mamonia Upper Triassic volcanic rocks. Data source of DMM, EM2 and HIMU fields ances, an evolution with time can be observed based are from Zindler & Hart (1986). A = mixing line between DMM on the petrology and chemistry of the volcanic rocks and HIMU. B = mixing line between the DMM component and and their associated sediments. Figure 11 illustrates this a small percentage of EM2 (∼ 6%).C= mixing line between evolution. Cr-spinel- and olivine-bearing basalts occur HIMU and a mantle source enriched by a small percentage of as pillowed flows interbedded with radiolarian and EM2. manganiferous cherts, and their trace element chemistry is similar to that of MORB or depleted tholeiites. These features suggest that these rocks represent the most primitive lavas of the Mamonia Complex and trachytic sample CY01-24 appears to be derived from a were generated by high degrees of partial melting. They mixing between an enriched mantle and the HIMU likely represent the deepest levels of the submerged component. The Pb isotopic composition of this intra-oceanic shield volcanoes. With time, the sedi- enriched mantle source could be similar to a depleted mentary environment evolved and pelagic carbonate mantle source contaminated by a small percentage of sediments were deposited either as interpillow voids an Enriched Mantle 2 component. and/or interbedded with the radiolarian cherts. Con- The (143Nd/144Nd) ratios of the Mamonia volcanic i comitantly, volcanism changed from depleted tholeiites (Type 1) rocks are too low to be explained by a simple to porphyritic alkali basalts, through oceanic island mixing line between DMM and HIMU components tholeiitic and mildly alkaline intersertal basalts. This (see mixing line A in Fig. 10a). The Pb and Nd depleted evolution in magma chemistry can be attributed to a de- tholeiite compositions can be modelled by the mixing crease of the degree of partial melting of an OIB plume of a DMM mantle source with a small percentage and crystal fractionation in shallow magma reservoirs. (< 8 %) of an EM2 component without contribution During the last stages of intra-plate volcanism, shield of the HIMU component. The variations of the 143Nd/ volcanoes grew and the shallow emplacement of alkali 144Nd and 206Pb/204Pb compositions of the remaining basalts and trachytes was followed by the development samples (Type 2, 3 and 4) can be explained by the mix- of coral reefs. ing between the enriched component of the depleted tholeiites (a small percentage of EM2) and the HIMU 5.d. Comparison of the Late Triassic Mamonia volcanism component (mixing line C). The trachytic sample with that exposed in the Tethyan belt CY01-43, characterized by the lowest 206Pb/204Pb ratio (Table 2), shows isotopic compositions which could Late Triassic volcanism is widely exposed in the potentially correspond to those of the component of the Tethyan belt from Albania to the Indus Tsang Po suture mixing line C (a depleted mantle source contaminated zone of the Himalayan Ranges (Fig. 1). In SW Turkey by less than 6 % of an EM2 component). (Antalya, Fig. 1), the Late Triassic volcanic suite Thus, we can assume that three major components consists of pillowed basaltic flows and hyaloclastites contributed to the genesis of the Mamonia suite: (1) a interbedded with Halobia-bearing pelagic limestones depleted mantle source, (2) recycled continental crust and red radiolarian cherts. They form an allochthonous (< 5 %) and (3) an HIMU enriched source. unit (the Kara Dere Sayrun unit of the Middle Antalya 14 H. LAPIERRE AND OTHERS

Figure 11. Reconstruction of the lithostratigraphic succession of the Mamonia Complex, showing the evolution with time of the Late Triassic volcanism and associated sedimentation. For explanation of type graphs see Figure 6.

Nappes), tectonically sandwiched between the Late In Oman, Late Triassic volcanic rocks are wide- Cretaceous limestones and Tertiary sediments depos- spread in the Hawasina Nappes complex. The Hawasina ited on the Arabian platform and the Late Cretaceous Nappes are thrust on the Arabian platform and support ophiolitic rocks (mantle rocks and ultramafic to mafic the ophiolitic Semail nappe (Glennie et al. 1974; cumulates) (J. Marcoux, unpub. thesis, Univ. Paris VI, Bechennec´ et al. 1989, 1991; Blendinger, Van Vliet 1987). The Late Triassic sedimentary sequence (sand- & Hughes Clarke, 1990; Pillevuit et al. 1997). New stones with fossil plant remains, Halobia limestones isotopic data (Chauvet et al. unpub. data) show that and red radiolarian cherts) is strongly similar to that they present OIB affinities. exposed in the Mamonia Complex. The alkaline affinity In Ladakh (Himalayan ranges), Late Triassic vol- of the Late Triassic volcanic rocks from SW Turkey canic rocks are exposed along the Indus Tsang Po has been first shown by Juteau (1975) on the basis suture zone, and below the Late Jurassic Spontang of preserved igneous mineralogy and major element and Nidar ophiolites. They belong to distinct thrust chemistry. New geochemical data (Maury et al. unpub. sheets (Photang sheet or Drakkar Po melange)´ con- data) show that they display OIB affinities. sisting of tectonic melanges´ and distinct volcanic In northern Syria (Fig. 1), the Late Triassic vol- suites associated with oceanic sediments (Colchen, canic and sedimentary rocks occur as blocks, broken Mascle & Van Haver, 1986; Reuber, Colchen & formations and disrupted sheets within the Baer-Bassit¨ Mevel, 1987; Corfield, Searle & Green, 1999). The Melange´ (Al-Riyami & Robertson, 2002), which is Late Triassic section consists of clinopyroxene-phyric sandwiched between the Arabian continental margin basaltic massive and pillowed flows interbedded with and the ophiolitic nappes. The Late Triassic volcanic Halstatt facies limestone also commonly found along rocks consist of basaltic pillow lavas and rare hyalo- the interstices of pillow lavas. The Late Triassic clastites interbedded with Halobia-bearing hemipelagic volcanic rocks are classified as alkali basalts by Reuber, limestone, ribbon radiolarite, turbiditic calcarenite Colchen & Mevel (1987) and Corfield, Searle & Green and/or massive pink micritic limestone. All these sed- (1999). New isotopic data (Chauvet et al. unpub. iments were dated as Late Triassic in age by Delaune- data) show that their εNd ratios (5 < MgO wt % < 6; Mayere` (1984). The Late Triassic volcanic rocks 2 < TiO2 wt % < 3) range between +4.3 and +5.3 and contain large phenocrysts of kaersutitic hornblende, fall in the range of the Mamonia and Antalya nappe sericitized plagioclase and titaniferous augite set in a suites. Their trace element chemistry is similar to that glassy groundmass now altered to zeolite, chlorite and of the intersertal basalts (Type 3) from SW Cyprus, epidote (Al-Riyami & Robertson, 2002). An alkaline but differs from that of SW Turkey by lower incom- affinity is shown by their major and trace element patible trace element contents (Maury et al. unpub. chemistry (Al-Riyami & Robertson, 2002). data). The Mamonia Complex 15

In the Himalayan and Oman ranges, rifting occurred Le Roex et al. (1983, 1985) showed that the influence of earlier than in the eastern Mediterranean. During Per- Bouvet plume has been registered by the oceanic basalts mian times, (1) the Neotethyan opening was preceded as far as 1200 km from the hot spot. Therefore, we by the emplacement of pre-rift continental flood basalt cannot exclude the presence of an oceanic realm during (Panjal traps in the Himalayan area: Bassoullet et al. the Late Triassic (Robertson, 2000). According to our 1980a; Honegger et al. 1982; Vannay & Spring, 1993) data, none of the Mamonia volcanic rocks experienced and (2) syn-rift tholeiitic and alkaline volcanic rocks contamination by the continental crust (no Nb and Ta erupted on the rifted Arabian platform while alkaline negative anomalies, positive εNd values), a feature con- (high Ti) and tholeiitic (low Ti) melts were emplaced sistent with their emplacement within an oceanic in the oceanic basin, floored by oceanic or transitional domain. crust (Bechennec´ et al. 1989, 1991; Maury et al. A question remains: is the Late Triassic volcanism of 2003; Lapierre et al. 2004). In the Himalayan ranges, the eastern Mediterranean linked to the opening of the remnants of a Late Permian volcanism are tectonically main Neotethyan Ocean or to that of small southerly imbricated with the Late Triassic alkaline basalts and neighbouring basins? According to most plate tectonic interbedded with platform limestones; they consist of reconstructions (Stampfli, Marcoux & Baud, 1991; alkaline phonolites, the Nd composition of which sug- Robertson, 2000; Stampfli et al. 2001), the Late Triassic gests that they derived from an enriched mantle source igneous event is linked to the break-up of the northern without crustal contamination (Chauvet et al. unpub. Gondwana margin and the opening of small ocean data). basins, located south of the Neotethyan realm and sep- In short, the Late Triassic volcanism exhibits features arated from the main ocean by rifted continental frag- of within-plate magmas (high contents in incompatible ments where platform carbonates were deposited. The elements, Nd and Pb isotopic ratios that fall in the Kyrenia Range in northern Cyprus and the Bey Daglari range of OIB) with no evidence of contamination by in southern Turkey (Robertson & Woodcock, 1980) the continental crust all along the western Tethyan may represent such fragments. Thus, the Late Triassic belt (Antalya to Indus). In the eastern Mediterranean, Mamonia within-plate volcanism likely erupted in a alkali basalts and hawaiites are present everywhere small southerly Neotethyan basin floored by oceanic (Turkey, Syria, Cyprus) while trachytes and tholeiites crust (Robertson, 2000), located south of the Kyrenia are found solely in SW Cyprus. No evidence of initial platform and north of the Eratosthenes seamount continental rifting of the Arabian passive margin is (Krashneninnikov et al. 1994; Kempler, 1998). The preserved, either in the Mamonia Complex, or in the Late Triassic sediments of the Mamonia Formation Antalya Nappes or Baer-Bassit¨ Melange.´ The oldest (Ayios Photios Group, Fig. 3) could represent the rem- known units are tholeiitic and alkaline volcanic rocks nants of the northern passive rifted margin of a conti- and related pelagic sediments (radiolarian cherts and nental micro-plate (Malpas, Calon & Squires, 1993; Halobia limestones), together with redeposited carbon- Robertson, 2000) rifted from the Gondwana margin. ates of shallow-water derivation and reefal limestones. The Petra tou Romiou volcanic rocks (Dhiarrizos The inferred setting for the Triassic volcanism of Group, Fig. 3) likely represent the remnants of eastern Mediterranean is an oceanic basin, located oceanic islands, formed outboard of the continental north of the Arabian–African plate. Tectonic slices micro-plate, currently represented by the Eratosthenes of the Mamonia Formation (Fig. 3) and dismembered seamount. units of the Baer-Bassit¨ Melange,´ and possibly the Another question concerns the structural evolution Middle Antalya nappe, can be restored as a continuous of the Mamonia Complex. Everywhere in the Tethyan Late Triassic–Late Cretaceous deep-water succes- belt, the Triassic volcanic rocks are thrust by the sion consistent with this Triassic ocean basin inter- ophiolitic nappes and themselves thrust upon the pretation. Gondwanian platform. The only exception seems to be Cyprus and some local sections in Baer-Bassit,¨ where out-of-sequence thrusting occurred (Al-Ryami 5.e. Geodynamic implications: Late Triassic Mamonia & Robertson, 2002). within-plate volcanism and the Neotethys opening In our opinion, as Cyprus suffered several tectonic Malpas, Calon & Squires (1993) suggested that part events (Grand et al. 1993; Bailey, Holdsworth & of the Mamonia Upper Triassic tholeiitic basalts (N- Swarbrick, 2000), out-of-sequence thrusting affected MORB affinities) could represent remnants of an Cyprus in the same way as Baer-Bassit.¨ This is demon- oceanic crust. However, our results show that the strated by the section of Ayia Varvara (Fig. 2b), where Mamonia basalts which are the closest to N-MORB we observe the superposition of lavas of the Mamonia type on the basis of Nd and Pb isotope compositions Complex, below a sheet of amphibolite, and below a were derived in fact from the partial melting of an sheet of peridotite. This kind of superposition (ophio- enriched OIB-type mantle source. Therefore, the Late lite–metamorphic sole–Triassic lavas), observed every- Triassic Mamonia volcanic suite is linked to the activity where in the Tethyan belt, is the result of the oldest of a hot spot perhaps not located near an oceanic ridge. tectonic event. In Cyprus the original tectonic pile was 16 H. LAPIERRE AND OTHERS

Figure 12. Schematic reconstruction of the structural pattern of the Troodos and Mamonia complexes involving two tectonic events of Late Cretaceous age. later more or less modified by superposed younger Late Triassic volcanism similar to that of the tectonic events. Mamonia Complex can be traced from the Himalayas to the Eastern Mediterranean (southern Taurides, Baer-¨ Bassit) through Oman, and was likely located offshore 6. Conclusions with respect to the southern Neotethyan passive margin. Our results show that the Mamonia Complex (SW Finally, Nd and Pb isotope compositions of the depleted Cyprus) represents remnants of Late Triassic intra- olivine tholeiites show that these rocks cannot represent oceanic within-plate volcanism, which evolved with remnants of a Late Triassic normal oceanic crust. time. Volcanic activity started with the eruption of The present day structural pattern of the Mamonia depleted olivine tholeiites (Type 1) associated with Complex and Troodos–Akamas ophiolites is probably deep basin siliceous and/or calcareous sediments, ac- due to two compressional events. The older one (F1, companied and/or followed by oceanic island tholeiites Fig. 12), related to the obduction of the ophiolites and (Type 2). With time, volcanism evolved towards the overthrust of deep-basin sedimentary and volcanic highly phyric alkali basalts (Type 3) enriched in the rocks upon the Neotethyan margin, took place during most incompatible elements (Nb, Ta, Th) and LREE, Maastrichtian time. The younger one (F2, Fig. 12) was interbedded with pelagic Halobia-bearing limestones related to the tectonic imbrication of the Mamonia and or reef limestones. Highly LREE-enriched trachytes Troodos complexes which also occurred during the (Type 4) characterize the end of volcanic activity. Maastrichtian with a vergence similar to that of the The trace element features of the four rock types first event. are likely linked to different partial melting ratios of heterogeneous OIB sources. Nd and Pb isotope ratios Acknowledgements. This work was funded by the teams suggest that the mildly alkali basalts derived from UMR 5025 of the Centre National de la Recherche Scienti- heterogeneous enriched mantle sources. The trachytes fique, Universite´ Joseph Fourier (Grenoble) and Universitede´ Savoie. We thank Dr L. A. Coogan and anonymous reviewers cannot be derived by fractional crystallization of the for their helpful comments to improve the manuscript. This alkali basalts but more likely from partial melting at paper is dedicated to the memory of our friend Henriette depth of mafic material that shares with the alkali Lapierre, first author of this manuscript, who died suddenly basalts similar trace element and isotopic compositions. on 14 January 2006 during a field excursion in Syria. The Mamonia Complex 17

Henriette started her scientific career working on the geology BRAGIN,N.Y.,BRAGINA,L.G.&KRYLOV,K.A. of Cyprus 40 years ago during her Ph.D. and prematurely 2000. Albian–Cenomanian deposits of the Mamonia ended it with the present work. Complex, southwestern Cyprus. In Proceedings of the Third International Conference on the Geology of References the Eastern Mediterranean, Nicosia (eds I. Panayides, C. Xenophontos and J. Malpas), pp. 309–17. Cyprus ABOUCHAMI,W.,GALER,S.J.G.&HOFMANN, A. W. 2000. Geological Survey. High precision lead isotope systematics of lavas from the CANNAT,M.&MASCLE, G. 1990. Reunion´ extraordinaire Hawaiian Scientific Drilling Project. Chemical Geology de la Societ´ eG´ eologique´ de France en Himalaya du 169, 187–209. Ladakh. Bulletin de la Societ´ eg´ eologique´ de France (s. ALLEGRE` ,C.J.,LEWIN,E.&DUPRE´, B. 1988. A Coherent 8) t. VI(4), 553–82. Crust Mantle Model for the Uranium Thorium Lead CLUBE,T.M.&ROBERTSON, A. H. F.1986. The paleorotation Isotopic System. Chemical Geology 70, 211–34. of the Troodos ophiolite, Cyprus, in the Late Mesozoic– AL-RIYAMI,K.,ROBERTSON,A.H.F.,XENOPHONTOS,C., Early Cenozoic plate tectonic framework of the Eastern DANELIAN,T.&DIXON, J. E. 2000. Tectonic evolution Mediterranean. Surveys in Geophysics 8, 239–55. of the Mesozoic Arabian passive continental margin and COLCHEN, M., MASCLE,G.&VANHAV E R ,TH. 1986. Some related ophiolite in Baer-Bassit¨ region (NW Syria). In aspects of the collision tectonics in the Indus suture Proceedings of the Third International Conference on zone, Ladakh Himalaya. In Collision Tectonics (eds the Geology of the Eastern Mediterranean, Nicosia (eds M. P. Coward and A. C. Ries), pp. 173–84. Geological I. Panayides, C. Xenophontos and J. Malpas), pp. 61–81. Society of London, Special Publication no. 19. Cyprus Geological Survey. CORFIELD,R.I.,SEARLE,M.P.&GREEN,O.R. AL-RIYAMI,K.&ROBERTSON, A. H. F. 2002. Mesozoic sed- 1999. Photang thrust sheet: An accretionary complex imentary and magmatic evolution of the Arabian conti- structurally below the Spontang ophiolite constraining nental margin, northern Syria: Evidence from the Baer-¨ timing and tectonic environment of ophiolite obduction, Bassit Melange. Geological Magazine 139, 395–420. Ladakh Himalaya, NW India. Journal of the Geological BAILEY,W.R.,HOLDSWORTH,R.E.&SWARBRICK,R.E. Society, London 156, 1031–44. 2000. Kinematic history of a reactivated oceanic suture: DELAUNE-MAYERE` , M. 1984. Evolution of a Mesozoic the Mamonia Complex Suture Zone, SW Cyprus. passive continental margin: Baer-Bassit (NW Syria). In Journal of the Geological Society, London 157, 1107– The geological evolution of the Eastern Mediterranean 26. (eds D. J. Dixon and A. H. F. Robertson), pp. 151– BARRAT,J.A.,KELLER,F.&AMOSSE´, J. 1996. Determination 75. Geological Society of London, Special Publication of rare earth elements in sixteen silicate reference no. 17. samples by ICP-MS after Tm addition and ion exchange DELAUNE-MAYERE` ,M.&PARROT, J.-F. 1976. Evolution du separation. Geostandards Newsletter 20, 133–9. Mesozo´ ¨ıque de la marge continentale meridionale´ du BASSOULLET,J.P.,BOULIN,J.,COLCHEN, M., MARCOUX, bassin tethysien´ oriental d’apres` les etudes´ des series´ J., MASCLE,G.&MONTENAT, C. 1980a. Evolution des sedimentaires´ de la region´ ophiolitique du NW syrien. domaines tethysiens´ du pourtour du bouclier indien du Cahiers ORSTOM, Serie´ Geologie´ 8(2), 173–84. Carbonifere` au Cretac´ e.´ Geologie´ des chaˆınes alpines DUMONT,J.-F.,GUTNIC, M., Z, J. & POISSON, A. 1972. Le issues de la Tethys.´ Colloque C5, 26eme` Congres` Trias des Taurides occidentales (Turquie). Definition´ du Geologique´ International, Paris. Memoires´ du Bureau bassin Pamphylien: un nouveau domaine a` ophiolites de Recherches Geologiques´ et Minieres` 115, 180–98. alamargeexternedelacha` ˆıne taurique. Zeitschrift BASSOULLET,J.P.,COLCHEN, M., JUTEAU,T.,MARCOUX,J. der Deutschen Geologischen Gesellschaft 123, 385– &MASCLE, G. 1980b. L’edifice´ des nappes de Zanskar 409. (Ladakh, Himalaya). Comptes Rendus de l’Academie´ EALEY,P.J.&KNOX, G. J. 1975. The pre-Tertiary rocks of des Sciences, Paris 290, 389–92. S.W. Cyprus. Geologie en Mijnbouw 54, 85–100. BECHENNEC´ ,F.,LE METOUR´ ,J.,RABU,D.,BEURRIER, M., GASS, I. G. 1980. The Troodos massif: Its role in the unravel- BOURDILLON-JEUDY-DE-GRISSAC,C.,DE WEVER,P., ling of the ophiolite problem and its significance in the TEGYEY,M.&VILLEY, M. 1989. Geologie´ d’une chaˆıne understanding of constructive plate margin processes. In issuedelaTethys:´ les montagnes d’Oman. Bulletin de Ophiolites (ed. A. Panayiotou), pp. 21–3. Proceedings la Societ´ eg´ eologique´ de France (s. 8) t. V(2), 231–40. International Ophiolite Symposium Cyprus, Nicosia. BECHENNEC´ ,F.,TEGYEY, M., LE METOUR´ ,J.,LEMIERE` , GLENNIE,K.W.,BOEUF,M.G.,HUGHES CLARKE,M.W., B., LESCUYER,J.-L.,RABU,D.&MILESI´ , J.-P. 1991. MOODY-STUART, M., PILAAR,W.F.&REINHART,B. Igneous rocks in the Hawasina nappes and the Hajar M. 1974. Geology of the Oman Mountains. Verhan- supergroup, Oman mountains: their significance in the delingen van het Koninklijk Nederlands geologisch birth and evolution of the composite extensional margin minjbouwkundig Genootschap [Transactions of the of Eastern Tethys. In Ophiolite genesis and evolution Royal Dutch Geological and Mining Society] vol. 31, of the oceanic lithosphere (ed. Director at General of part 1, 423 pp. Minerals), pp. 569–611. Ministry of Petroleum and GRAND,T.,LAPIERRE,H.,MASCLE,G.,OHNENSTETTER,M. Minerals, Oman. &ANGELIER, J. 1993. Superimposed tectonics of the BLENDINGER,W.,VAN VLIET,A.&HUGHES CLARKE,M. Cyprus ophiolitic massifs. Tectonics 12, 93–101. W. 1990. Updoming, rifting and continental margin HONEGGER,K.,DIETRICH,V.,GANSSER,A.,HOENI,M.& development during the Late Paleozoic in Northern TROMMSDORFF, V. 1982. Magmatism and metamorph- Oman. In The geology and tectonics of the Oman ism in the Ladakh Himalayas (the Indus-Tsangpo suture region (eds A. H. F. Robertson, M. P. Searle and A. C. zone). Earth and Planetary Science Letters 60, 253–92. Ries), pp. 27–37. Geological Society of London, Special JUTEAU, T. 1975. Les ophiolites des nappes d’Antalya (Taur- Publication no. 49. ides occidentales, Turquie): petrologie´ d’un fragment de 18 H. LAPIERRE AND OTHERS

l’ancienne crouteˆ oceanique´ tethysienne?´ Sciencedela Southern Ocean: implications for the westward influ- Terre Memoire´ no. 5. Nancy, France, 692 pp. ence of the Bouvet mantle plume. Contributions to KEMPLER, D. 1998. Eratosthenes Seamount: the possible Mineralogy and Petrology 90, 367–80. spearhead of incipient continental collision in the MAHEO´ ,G.,BERTRAND,H.,GUILLOT,S.,MASCLE,G., Easternmost Mediterranean. In Proceedings of the PECHERˆ ,A.,PICARD,C.&DESIGOYER, J. 2000. Les Ocean Drilling Program, Scientific Results, vol 160 ophiolites cretac´ ees´ du Sud Ladakh (NW Himalaya, (eds A. H. F. Robertson, K.-C. Emeis, C. Richter and A. Inde): Temoins´ d’un arc immature intra-oceanique.´ Camerlenghi), pp. 68–71. College Station, Texas. Comptes Rendus de l’Academie´ des Sciences, Paris 300, KIEFFER,B.,ARNDT,N.T.&WEISS, D. 2002. Petrology 289–95. and geochemistry of a bimodal alkalic shield volcano, MALPAS,J.,CALON,T.&SQUIRES, G. 1993. The devel- Site 1139, Kerguelen Plateau. Journal of Petrology 43, opment of a Late Cretaceous microplate suture zone 1259–86. in SW Cyprus. In Magmatic Processes and Plate KRASHENINNIKOV,V.A.,UDINTSEV,G.B.,MOURAVIOV, Tectonics (edsH.Prichard,T.Alabaster,N.B.Harrisand V. & H ALL, J. K. 1994. Geological structure of the C. R. Neary), pp. 177–95. Geological Society of Eratosthenes Seamount. In Geological structure of London, Special Publication no. 76. the North-Eastern Mediterranean (Cruise 5 of the MALPAS,J.,XENOPHONTOS,C.&WILLIAMS, D. 1992. The Research Vessel Akademik Nikolaj Strakhov) (eds V.A. Ayia Varvara Formation of SW Cyprus, a product of Krasheninnikov and J. K. Hall), pp. 113–30. Jerusalem, collisional tectonics. Tectonophysics 212, 193–211. Israel: Historical Productions-Hall, Ltd. MARCOUX, J. 1970. Age carnien des termes effusifs du LAPIERRE, H. 1968. Decouverte´ d’une serie´ volcano- cortege` ophiolitique des Nappes d’Antalya (Taurus Ly- sedimentaire´ probablement d’ageˆ Cretac´ esup´ erieur´ au cien –oriental, Turquie). Comptes Rendus de l’Academie´ S-W de l’ˆıle de Chypre. Comptes Rendus de l’Academie´ des Sciences, Paris 271, 227–41. des Sciences, Paris 266, 1817–20. MAURY,R.C.,BECHENNEC´ ,F.,COTTEN,J.,CAROFF, M., LAPIERRE, H. 1975. Les formations sedimentaires´ et CORDEY,F.&MARCOUX, J. 2003. Late Permian plume- eruptives´ des nappes de Mamonia et leurs relations avec related magmatism of the Hawasina Nappes and the le Massif du Troodos (Chypre occidentale). Memoires´ Arabian Platform: Incidences on the evolution of the de la Societ´ eg´ eologique´ de France no. 123, 127 pp. Neotethyan margin in Oman. Tectonics 22(6), 1073, LAPIERRE,H.&PARROT, J.-F. 1972. Identiteg´ eologique´ des doi:10.1029/2002TC001483. regions´ de Paphos (Chypre) et de Baer-Bassit¨ (Syrie). MCCULLOCH,M.T.&WASSERBURG, G. J. 1978. Sm–Nd Comptes Rendus de l’Academie´ des Sciences, Paris 274, and Rb–Sr chronology of continental crust formation. 1999–2002. Science 200, 1003–11. LAPIERRE,H.&ROCCI, G. M. 1970. Un bel exemple MCLEOD, C. J. 1990. Role of the Southern Troodos d’association cogen´ etique´ laves-radiolarites-calcaires: Transform Fault in the rotation of the Cyprus microplate: la formation triasique de Petra´ tou Romiou (Chypre). Evidence from the Eastern Limassol Forest Complex. In Comptes Rendus de l’Academie´ des Sciences, Paris 268, Ophiolites. Oceanic Crustal Analogues (eds J. Malpas, 2637–40. E. Moores, A. Panayiotou and C. Xenophontos), pp. 75– LAPIERRE,H.&ROCCI, G. M. 1976. Le volcanisme alcalin 86. Proceedings of ‘Troodos 87’ Symposium. Cyprus du Sud-Ouest de Chypre et le problemedel’ouverture` Geological Survey. des regions´ tethysiennes´ au Trias. Tectonophysics 30, MCLEOD,C.J.&MURTON, B. J. 1995. On the sense of the slip 299–313. of the Southern Troodos transform fault zone. Geology LAPIERRE,H.,DUPUIS,V.,MERCIER DELEPINAY´ ,B.,TARDY, 23, 257–60. M., RUIZ,J.,MAURY,R.C.,HERNANDEZ,J.&LOUBET, MURTON, B. J. 1990. Was the Southern Troodos Transform M. 1997. Is the Lower Duarte Igneous Complex (His- Fault a victim of microplate rotation? In Ophiolites. paniola) a remnant of the Caribbean plume generated Oceanic Crustal Analogues (eds J. Malpas, E. Moores, oceanic plateau? Journal of Geology 105, 111–20. A. Panayiotou and C. Xenophontos), pp. 87–98. LAPIERRE,H.,SAMPER,A.,BOSCH,D.,MAURY,R.C., Proceedings of ‘Troodos 87’ Symposium. Cyprus BECHENNEC´ ,F.,COTTEN,J.,DEMANT,A.,BRUNET,A., Geological Survey. KELLER,F.&MARCOUX, J. 2004. The Tethyan plume: PARROT, J.-F. 1974a. Les differentes´ manifestations effusives Geochemical diversity of Middle Permian basalts from de la region´ ophiolitique du Baer-Bassit¨ (N-W de la the Oman rifted margin. Lithos 74, 167–98. Syrie), Comparaison petrographique´ et geochimique.´ LEGENDRE,C.,MAURY,R.C.,SAVANIER,D.,COTTEN,J., Comptes Rendus de l’Academie´ des Sciences, Paris 279, CHAUVEL,C.,HEMOND´ ,C.,BOLLINGER,C.,GUILLE,G., 627–30. BLAIS,S.&ROSSI, P. 2005. The origin of intermediate PARROT, J.-F. 1974b. L’assemblage ophiolitique du Baer-¨ and evolved lavas in the Marquesas archipelago: an Bassit (N-W de la Syrie): etude´ petrographique´ et example from Nuku Hiva island (French Polynesia). geochimique´ du complexe filonien, des laves qui lui sont Journal of Volcanology and Geothermal Research 143, associees´ et d’une partie des formations effusives com- 293–317. prises dans le volcano-sedimentaire.´ Cahiers ORSTOM, LE ROEX,A.P.,DICK,H.J.B.,ERLANK,A.J.,REID, Serie´ Geologie´ 6(2), 97–126. A. M., FREY,F.A.&HART, S. R. 1983. Geochemistry, PILLEVUIT,A.,MARCOUX,J.,STAMPFLI,G.&BAUD,A. mineralogy and petrogenesis of lavas erupted along 1997. The Oman Exotics: a key to the understanding the southwest Indian Ridge between the Bouvet Triple of the Neotethyan geodynamic evolution. Geodinamica Junction and 11 Degrees East. Journal of Petrology 24, Acta 10, 209–38. 267–318. REUBER,I.,COLCHEN,M.&MEVEL, C. 1987. The LE ROEX,A.P,DICK,H.J.B.,REID,A.M.,FREY,F.A., geodynamic evolution of the South-Tethyan margin in ERLANK,A.J.&HART, S. R. 1985. Petrology and Zanskar, NW-Himalaya, as revealed by the Spongtang geochemistry from the American–Antarctic Ridge, ophiolitic melanges. Geodinamica Acta 1, 283–96. The Mamonia Complex 19

ROBERTSON, A. H. F. 1977. The Kannaviou, Cyprus: vol- STAMPFLI, G. M., BOREL,G.,CAVA Z Z A ,W.,MOSAR,J.& caniclastic sedimentation of a probable Late Cretaceous ZIEGLER, P.A. 2001. The Paleotectonic Atlas of the Peri- volcanic arc. Journal of the Geological Society, London Tethyan Domain (CD-ROM). European Geophysical 133, 447–66. Society. ROBERTSON, A. H. F. 2000. Tectonic evolution of Cyprus in SUN,S.S.&MCDONOUGH, W. F. 1989. Chemical and its easternmost Mediterranean setting. In Proceedings isotopic systematics of ocean basalts: Implications for of the Third International Conference on the Geology of the mantle composition and processes. In Magmatism in the eastern Mediterranean, Nicosia (eds I. Panayides, the ocean basins (eds A. D. Saunders and M. J. Norry), C. Xenophontos and J. Malpas), pp. 11–44. Cyprus pp. 313–45. Geological Society of London, Special Geological Survey. Publication no. 42. ROBERTSON,A.H.F.&WALDRON, J. W.1990. Geochemistry SWARBRICK, R. E. 1993. Sinistral strike-slip and transpres- and tectonic setting of Late Triassic and Late Jurassic– sional tectonic in an ancient ocean setting: The Mamonia Early Cretaceous basaltic extrusives from the Antalya complex, southwest Cyprus. Journal of the Geological Complex, south west Turkey, In Proceedings of the Society, London 150, 381–92. International Earth Sciences Congress on Aegean SWARBRICK,R.E.&NAYLOR, M. A. 1980. The Region (eds M. Y. Savasc¸in and A. H. Eronat), pp. 279– Kathikas Melange, southwest Cyprus: Late Creta- 99. IESCA Publication no. 2, Izmir, Turkey. ceous, submarine debris ﬂows. Sedimentology 27, 63– ROBERTSON,A.H.F.&WOODCOCK, N. H. 1980. Tectonic 78. setting of the Troodos in the East Mediterranean. SWARBRICK,R.E.&ROBERTSON, A. H. F. 1980. Revised In Ophiolites; Proceedings, International Ophiolite stratigraphy of the Mesozoic rocks of southern Cyprus. Symposium, Nicosia (ed. A. Panayiotou), pp. 36–49. Geological Magazine 117, 547–63. Cyprus Geological Survey. TODT,W.,CLIFF,R.A.,HANSER,A.&HOFMANN,A.W. ROBERTSON,A.H.F.&WOODCOCK, N. H. 1982. Sed- 1996. Evaluation of a 202Pb–205Pb double spike for imentary history of the segment of the Mesozoic– high-precision lead isotope analysis. In Earth processes: Tertiary Antalya continental margin, Turkey. Eclogae Reading the isotopic code (eds A. Basu and S. Hart), Geologicae Helvetiae 75, 517–62. pp. 429–37. American Geophysical Union, Geophysical ROCCI, G. M., BAROZ,F.,Bebien,´ J., DESMET,A.,LAPIERRE, Monograph no. 95. H., OHNENSTETTER,D.,OHNENSTETTER,M.&PAR- VANNAY,J.C.&SPRING, L. 1993. Geochemistry of the ROT, J.-F. 1980. The Mediterranean ophiolites and continental basalts within the Tethyan Himalaya of their related Mesozoic volcano-sedimentary sequences. Lahul-Spiti and SE Zanskar, NW India. In Himalayan In Ophiolites; Proceedings, International Ophiolite Tectonics (eds P. J. Treloar and M. P. Searle), pp. 237– Symposium, Nicosia (ed. A. Panayiotou), pp. 273–86. 49. Geological Society of London, Special Publication Cyprus Geological Survey. no. 74. SEARLE, M. P. 1983. Stratigraphy, structure and evolution of WHITE,M.W.,ALBAREDE` ,F.&TELOUK, F. 2000. High- the Tibetan–Tethys zone in Zanskar and the Indus suture precision analysis of Pb isotopic ratios by multi-collector zone in the Ladakh Himalaya. Transactions of the Royal ICP-MS. Chemical Geology 167, 257–70. Society of Edinburgh, Earth Sciences 73, 205–19. WINCHESTER,J.A.&FLOYD, P. A. 1977. Geochemical SHERVAIS, J. W. 1982. Ti–V plots and the petrogenesis discrimination of different magma series and their differ- of modern and ophiolitic lavas. Earth and Planetary entiation products using immobile elements. Chemical Science Letters 59, 101–18. Geology 20, 325–43. STAMPFLI,G.M.,MARCOUX,J.&BAUD, A. 1991. ZINDLER,A.&HART, S. R. 1986. Chemical geodynamics. Tethyan margin in space and time. Palaeogeography, Annual Review of Earth and Planetary Sciences 14, Palaeoclimatology, Palaeoecology 87, 373–409. 493–571.