J. geol. Soc. London, Vol. 138, 1981, pp. 83-92, 4 figs, 3 tables. Printed in Northern Ireland. Detrital blue sodic amphibole in Recent sediments, southern coast,

M. A. Mange-Rajetzky

SUMMARY:Detrital blue sodic amphibole, sporadiclawsonite and pumpellyiteoccur in beach and river sediments between Gazipasa and Manavgaton the southern Turkish coast. This area lies S of the metamorphic Alanya massif, which contributes to the detritus, but blueschists havenot previously been recorded in the region.The blue amphiboles have a provincial variation related to differing conditions during their formation. In the eastern region, in the vicinity of Gazipasaand Demirtas, homogeneous glaucophanes, sometimes with remnant Ca-amphiboles,are characteristic. In thewestern region the grainsexhibit a considerable variation of optical and physical properties and are crossitic-glaucophane, crossite and occasion- ally magnesio-riebeckite. Theefficacy of sedimentary mineralogy in reconstructing a hinterland is demonstrated.

The geology of southern Turkey has attracted resear- Studies of the composite nappe system of the nearby chers for a number of years. Of particular interest is region by agroup of Frenchresearchers the region bordered by the towns Anamur, Beysehir, focussed particularly on the mode of origin and em- Isparta and (Fig. l), where various nappe com- placement of the nappes of the‘Taurus occidental’ plexesindicate acomplicated geological structure. (Brunn1974; van derKaaden 1971; Monod et al. During the last 15 years several groups of geologists. 1974;Juteau 1975; Marcoux 1976;Dumont et al. applying the plate tectonic theory, have attempted to 1972;Delaune-Mayere et al. 1977and Ricou et al. unravel its evolution in terms of a collision process. 1974, 1975, 1979). Detrital blue sodic amphibole, lawsonite and pum- Investigation of the modern sedimentsof the south- pellyite occur in river and coastal sediments between ern Turkish coast began in 1969, when a team from Gazipasaand , supplied by riversdraining the Department of Geology,Imperial College, Lon- the metamorphic Alanya massif and its northern bor- don, in co-operation with M.T.A. (Turkish Geological derland.Blueschists indicate collision tectonics with Survey) started a comprehensivereconnaissance sur- conditions of high-pressuremetamorphism, and evi- vey of the area between Karatas and Antalya (Evans dence of their existence in the Alanya massif, where 1971).I joined the team in 1976 to investigate the they have not been recorded, has significant tectonic mineralogyand provenance of the river and coastal implications. sediments.During the course of thisanalysis blue The Alanya massif occupies the coastal range from sodic amphibole was encountered in beach and river theeastern of Anamurto Alanya and extends sediments from around Gazipasa and as faras westward behindTertiary formations as far as the Manavgat. Manavgatriver. Thearea has not beenstudied in detail, but it is known that metamorphic rocks of the Mineralogy greenschist facies constructing the schistose group are overlain by marbles and dolomites (Blumenthal 1951; Ageneral study of beach and river sediments was Peyronnet 1971; Brunn et al. 1971; Brinkmann 1976). based on material separated from the 53 to 350 pm Locally metamorphosedbauxite alsooccurs in the sandrange. The coarserfractions are dominated by massif. Papersdescribing regional and stratigraphic lithic fragments, composite and ferruginous grain, and details include Arni (1939), Altini (1944), Blumenthal the best mineral assemblages were obtained from the (1951),Erentoz (1956), Peyronnet (1967, 1971), 53 to 212 pm range. The followingminerals were Brunn et al. (1971,1975), Argyriadis (1974) and identified: Ricou et al. (1974). Amphiboles: Blue sodic amphibole, blue-green hornblende; The northern flank of the Alanya massif as far as smallamounts of brownhornblende, tremolite-actinolite Kopriilii is incontact with the Palaeozoic-Mesozoic and grunerite. formations of the nappe which contain radio- F‘yroxenes:Augite which includesdiopsidic, acmitic and titaniferous varieties; diopside, diallage, enstatite, hypers- larites and ophiolites. From Kopriilii to the Manavgat thene. The pyroxenes usually occur in small amounts but valley units of the Antalya nappe outcropin a narrow, becomedominant, together with someolivine, W of complex zone between the Mesozoic formations of the . and the limestones and marbles of Garnet andvarious micas show important local concentra- the Alanya massif. tions.

0016-7649/81/0100-0083$02.00 @ 1981 The Geological Society

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LEGEND 0 25 %ll5 “km N Scak n t Metamorphic rocks of the Alanyamassif Formations of Antalya nappe Mesozoic -Tertiary comprehensive series, main/y calcareous Massive peridotites

Miocene Wasse Terfiary/Ouaternary “~ectonicwindow” with units of the Antalya and Hadirn nappe Lake

lNnFX MAP

BLACK SEA

RC. 1. Schematic geological map showingthe structural units in the vicinity of the Alanya massif. After Brunn et al. (1973), Argyriadis (1974) and M.T.A. 1: 500,000 geological map of Turkey.

Characteristic metamorphic minerals include kyanite, andalu- petrologicalprovince, characterized dominantly by site and chloritoid. metamorphic minerals. The epidote group is represented by clinozoisite; epidote is The minerals indicating high-pressurelrelatively low not common. temperature metamorphism include glaucophane and Accessories are abundantin the 53-63 @m fractionand other members of theglaucophane-riebeckite series, includetourmaline, zircon, apatite, rutile, sphene, lawso- nite and pumpellyite. together with sporadic lawsonite and pumpellyite. The Light fraction: Lithic fragments, micas and quartz make up abundance of blueamphiboles wasestimated by the mass of the sediments. The grainsare often stained counts of 400-500 transparent minerals per sample, withiron-hydroxide. Radiolarian chert and fragments of but no attempt was madeto calculate the absolute volcanic matrix are common around Gazipasa and Manav- weight percentages of the individual mineral species, gat. Feldspars occur in minor quantities in all samples and since theabundant opaque minerals and composite are usually represented by sodic and intermediate plagio- grainswould have obscured theimportant ‘exotic’ clase. These grainsare poorly preserved. The sediments are mineral assemblages. Thepercentage data therefore rich in calcareous fragments, but during the preparation of indicate relative percentages (Table 1, Fig. 2). the samples for heavy mineral analysis these were removed by acid treatment. In a study of the mineralogy of the sediments of the Properties of the blue amphibole southernTurkish coast (Mange-Rajetzky 1979) the heavy mineraltechnique wasused and inferences Opticalanalyses weremade on the blueamphibole madeabout the petrography of thesource areas. from 4 samples containing large amounts of this min- Characteristicheavy mineral assemblages were dis- eral (Table 1). No attempt was made to determine the tinguished and their area1 distribution, in combination refractive indices because most of the coarser grains with light mineral data, enabled them to be mapped as showedslight encrustation or disintegration on the provinces, reflecting the petrographical nature of the surface. In the case of the finerclear and well pre- hinterland. servedgrains the small size made hand-picking and The present area constitutes part of a sedimentary observation difficult.

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LEGEND

I. , , , I ,, , ...... 2in 264 2l8212 k0 River samples 249 252278 257 258 265 271 239234214,204 221224 228 Coastal samples 240 226

FIG. 2. Generalizedgeological map showing sample locations and mineral units. After Argyriadis (1974) and M.T.A. 1:500,000 geological map of Turkey. Diagram below illustrates the distribution of blue sodic amphibole and associated minerals in the sediments.

The grains in sample 224 from the vicinity of De- All grains have a very low birefringence displaying mirtasare generally (110) cleavageflakes andare pale-grey, blue or pale greyish-yellow interference characterizedby short prismatic habit. The pleo- colours. Most exhibit zoned or mottled extinction and chroism is well expressed: 8 brightlavender-blue, y this, as well asthe (110) orientation, limited the sky-blue. On a few thin specimens a,almost colourless measuring of themain extinctionangle; grains on to pale yellow, was observed by rolling the grains on (110) show almost parallel extinction.The interference the slide. figure is usually clear and visual inspection (using the

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TABLE1: Percentages of blue sodic amphibole in some beach and river sediments

Mouth of Mouth of Mouth of Manaugat Ir. Locality Sedre Cay Afara Cay Karpuz Irmagi Riuer sand Sample No, 224 257 252 281

Size grade (pm) 53-63 25.1 17.0 13.3 12.5 63-125 15.3 3.0 12.2 7.9 125-210 14.7 6.1 10.2 3.4 210-300 2.3 11.1 12.3 1.7 0 0 0 1.0 0 0 300-350 0 Percentage of total grains counted in 53-300 15.9 12.3 10.7 5.9

data in Phillips 1971, p. 145) showed a range of the 2V varying within a single grain.Change of elongation 2V, opticaxial angle between 15 and 30°, occasion- in a single specimen is also common (Fig. 4C,D). ally (15". TheOAP is parallel to (010). The blue Grains with well developed prismatic form showed amphibolehas weakdispersion and positiveelonga- clear interference figures, occasionally strong disper- tion. Alteration of the grains is easily observed under sion and a great variation in 2V,, with values from 5 the stereoscopicmicroscope. Some are coated by or to 45". The opticaxial plane of thesegrains was altered to a white substance and are almost opaque parallel to (010); both positive and negative elonga- underthe polarizingmicroscope, only the thinner tions are recorded. edgesshowing the characteristic blue colour and Columnarand fibrousblue amphibolesfrequently pleochroism. form composite grains with white mica, clinozoisite or Blue sodic amphiboles with remnant Ca-amphibole epidote, sometimes with tremolite or hornblende and cores have been found in the sediments of the Gazi- rarely with albite (Fig. 4E). pasaarea. In acomposite grain from Delice Cay (Fig. 4A) the differing properties of the two am- X-ray and electronmicroprobe phiboles are expressed in contrasting interference col- analyses ours and positive elongation of the upper part of the grain, while the lower portion shows negative elonga- X-ray analysis, using a PhilipsDebye-Scherrer powder tion (Fig. 4B). camera, was carried out on blue amphiboles selected Samples 240, 252 and 257 from the region to the fromthe samplesused for determination of optical NW exhibit a wider variation of blue amphibole. Be- properties (Table 2). Grains from sample 224 display a sidethe short and long prismatic habit, columnar remarkably uniform powderpattern of pure aggregates were frequently encountered, especially in glaucophane,corresponding with thereference the coarser fractions. The deep, sometimes extremely glaucophanefrom California. Sample240 showsa dark, colour is characteristic and pleochroism shows 0 similar pattern,but inaddition to theglaucophane deep-blue withslight lavendertint and y deep peaks, magnesio-riebeckite is suggested on the basis of greenish-blue. Colour zoning is a constant phenome- thed spacings. Grainsfrom samples 252 and 257 non amongst these blue amphiboles, whichmay dis- indicate the structure of glaucophane and crossite. playa pale rimwith darkercore, a pale core and Chemicalanalysis was obtained by usinga Cam- darker rims, or irregular zoning. Optical discontinuity bridge Instruments Microscan V electron probe micro- usually accompanies this phenomenon, extinction and analyser,fitted with Linka EDS detector.Blue

TABLE 2: Main dA values of blue sodic amphiboles in orderof intensity

~~~ ~ ~~ Sample No. 224 8.24 3.04 2.68 4.45 3.35 = glaucophane 240 8.24 3.04 2.68 4.45 3.36 =glaucovhane- 240 3.10 4.21 3.10 240 = magnesio-riebeckite 252+257 8.283.36 2.68 3.04 2.51 = -daucophane 252+257 4.49 4.91 2.95 3.21 = crossite

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T-LE 3: Blue sodic amphibole analyses (wt.%)

Glaucophane with Ca- amphibole Crossitic Glaucophanes core glaucophanes Crossite TK 224 TK 240 TK 281 TK 226 252TK TK278 TK 278B

~~ SiO, 57.98 58.20 57.98 53.89 SiO, 54.39 56.63 48.71 55.81 11.03 11.47 10.04 11.94 9.18 11.94 10.04 AL0, 11.47 11.03 7.75 8.43 TiO, 0.00 0.00 0.06 0.440.39 0.01 0.16 Fe,O,* 0.165.38 1.14 4.87 4.351.29 4.29 15.60 9.82 11.64 13.86 12.75 Fe013.86 11.0211.64 9.80 9.82 15.60 MnO 0.05 0.05 0.00 0.080.07 0.15 0.00 MgO 9.30 9.50 8.296.20 10.16 7.28 6.97 CaO 0.21 0.47 0.98 0.700.75 6.53 1.34 NaZO 7.996.56 7.30 6.88 7.217.14 4.38 KZ0 0.00 0.03 0.090.04 0.250.08 0.03 Anhvdrous 97.27 98.38 97.00 96.67 98.12 96.22 95.88 96.22 98.12 96.67 97.00 totai 98.38 97.27

Number of cations on the basis of 23 oxygens: 7.998 7.972 7.972 7.050 7.925 7.899 7.826 7.899 7.925 7.050 7.972 Si 7.972 7.998 0.002 0.028 0.028 0.950 0.075 0.101 0.174 0.101 0.075 0.950 0.028AI" 0.028 0.002 AI" 1.792 1.824 1.663 1.087 1.440 1.087 1.663 1.824 1.792 AI" 1.270 1.226 0.005 0.048 0.001 0.043 0.017 Ti 0.043 0.0010.000 0.0480.000 0.005 0.118 0.016 0.139 0.467 0.458 0.532 0.588 0.532 0.458 0.467 0.139Fe3+ 0.016 0.118 1.131 1.262 1.864 1.188 1.362 1.683 1.549 1.683 1.362 1.188 1.864Fe2+ 1.262 1.131 Mn 0.007 0.0090.006 0.0180.000 0.008 0.000 1.953 1.898 1.320 2.191 1.729 1.509 1.576 1.509 1.729 2.191 1.320 Mg 1.898 1.953 0.069 0.031 0.115 1.013 0.106 0.152 0.208 0.152 0.106 1.013 0.115 Ca 0.031 0.069 1.952 2.122 1.978 1.229 1.956 1.937 1.847 1.937 1.956 1.229 1.978 Na 2.122 1.952 0.005 0.007 0.046 0.005 0.015 0.017 0.015 0.005K 0.046 0.0000.007 0.005

* Ferric iron was calculated using a computer program by Papike et al. (1974). The maximum Fe,O, value is given; this allows comparison with other sodic amphibole analyses from Turkey (Hall 1980, Okay 1980). The data of the analyses are plotted on the Miyashiro diagram (Fig. 3).

amphiboles were individually selected from the 4 sam- data suggest that amphiboles analysed from this region plesdescribed, and these were complemented with represent crossitic glaucophane, crossite and a minor grains from samples 278 and 281 (Table 3). amount of magnesio-riebeckite (Table 3; Fig. 3). Spot In additioncomposite grains formed by blueam- analyses made on anumber of singlegrains show phibole and other minuteminerals were analysed since considerable variation, which could be related to de- they could provide valuable information about miner- composition and should therefore be treatedcautiously. als associated with the blue amphiboles in the parent Electronmicroprobe analyses on compositegrains rocks. indicate that these include crossite + albite, epidote + Blue amphiboles of the Demirtas area show a re- albite+glaucophane, crossite+epidote+quartz, glauco- markable uniformity in chemicalcomposition. Both phane + epidote + biotite +paragonite and hornblende the analysis of the individualgrains and the several +quartz + albite. spot analyses made on thesegrains indicate Optical,physical and chemicalstudies of the blue glaucophane with negligible variation in the main ele- amphibolestherefore suggesta provincial variation. ments. Blue amphiboles selected fromsamples located Blue amphiboles in sediments between Gazipasa and W of Alanya, on the other hand, demonstrate a con- Demirtas display a fairly homogeneous character and siderable variation in Fe-Mg and A1 content, charac- composition, whereas those between Alanya and Man- teristically for the glaucophane-riebeckite series. The avgat show a remarkable variation.

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Jadeite coexistingwith blue amphibole is wide- spread in Alpine-type metamorphic terrains, but detri- taljadeite cannot be identifiedwith certainty. Ina number of samplescolourless, sometimesfibrous, clinopyroxenewith lower refractive indices, strong dispersion andanomalous interference colour has been observed, and this may be jadeite. Sphene and part of the clinozoisite may be primary accessories derived from blueschists. The percentages of these minerals increase or decrease in parallel with those of the blue amphibole. In addition a number of compositegrains of blue amphiboleand clinozoisite have been observed (Fig. 4H). Inseveral localitiesblue amphibolesare accom- panied by abundant micaceous grains. Since micas are 8 ubiquitous in the present environment these cannot be considered informative.With the exception of the X-ray determination of white micas from samples 224 and226 no further studywas made on them.The X-ray pattern of white micas indicated the presenceof G 100Fe3+/(Fe3++AlV'+Ti) MR 2M, muscovite and paragonite. Phengiticmicas are generally associated with blue FIG.3. Blue sodic amphibole compositions plotted amphiboles and their occurrencewith the detrital blue on the Miyashiro diagram. G= glaucophane; FG = amphiboles in thesediments isprobable. Peyronnet ferroglaucophane; MR = magnesio-riebeckite; R = (1971) reported phengitic micas in a number of loca- riebeckite.Open circles = blueamphiboles from tions in the Alanya massif. the eastern province; filled cricles = blue amphi- boles from the western province. Distribution of blue amphibole and associated minerals The relativepercentages of blue amphibole in river Mineralsassociated with and coastal samples, together with those of (presuma- blue amphibole bly primary) accessory minerals, were determined and the area1distribution of thevarious mineral assem- In samples rich in blue amphibole a few grains of a blages delineated (Fig. 2). colourless mineral with equidimensional habit andwell 1. Gazipasa:Ferruginous, micaceous and schistose frag- developed cleavages wereencountered (Fig. 4G). ments as well as garnet are the main constituents. Kyanite Theseexhibit a moderate relief,parallel extinction andandalusite are present insmall amounts. Blue am- and, depending on the thickness of the mineral, pale phibole is represented in minor percentages and appears to strong interference colours, strongdispersion of the to have grown at the expense of Ca-amphibole (Fig. 4A). optic axes and a large optic axial angle. Some grainsof Considerableamounts of purple-browntitaniferous, as this mineral displayed polygonization and, as a result, well as green, augite in samples 200 and 212 contrast with variableextinction. Identification of thesegrains as the predominantly metamorphic assemblage. These grains lawsonitewas made on opticalproperties, since the are associated with calcic plagioclase, chert and decom- small size and sporadic occurrence precluded further posedvolcanic matrix containing microlites or twinned plagioclasein thelight fraction. Titaniferous augite is analyses. Similar grains in the finer fractions showing abundant in the sediments of the Antalya region (Mange- decomposition along perfect cleavage directions may Rajetzky 1979); itis a characteristic constituent of the also be lawsonite. volcanic units (basaltic lavas, pillow lavas, sills and micro- Pumpellyite is often associated with blue amphibole gabbros) of the Antalya nappe (Juteau 1975). Titanifer- and lawsonite, but its occurrence as a detrital grain is ous augite suggests a correlation between the presumably unusual. Oneglaucophane grain intergrown witha volcanic formations, set tectonically in the metamorphic colourless to pale-yellow,slightly pleochroic fibrous schists in the vicinity of Gazipasa, and the similar units of mineral was found in sample 224. The latter showed the Antalya nappe. brownish-yellow and blue anomalous interference col- 2. Dernirtas:Schistose lithic fragments, sericite, biotite, chlorite and white mica are associated with abundant blue ours.In samples 252 and 257 similargrains were amphibole.Some of the latter showremnant Ca- encountered. These grains were identified as pumpel- amphibole cores. lyite on the basis of their crystal form and characteris- 3. Alanya: The sediments are rich in almandine garnet ac- tic interference colours (Fig. 4F). companied by opaque minerals, accessory tourmaline and

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FIG. 4. Scale bar represents 50 pm in all photomicrographs. A, Photomicrograph showing the conversion of a Ca-amphibole (top part) to blue sodic amphibole. B, Grain A under crossed nicols. On inserting an accessory plate the contrasting elongation of the two parts is well displayed. C, Fragment of a blue amphibole showing colour zoning. D, Grain C under crossed nicols. On inserting an accessory plate the grain exhibits varying elongation. E, Photomicrograph of fibrous blue amphiboles embedded in white mica. F, Photomicrograph of a weathered grain of pumpellyite. G, Photomicrograph of afragment of lawsonite.Alteration of the grainis well pronounced along cleavage directions. H, Prismatic fragment of a blue amphibole enclosing a small clinozoisite.

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apatite. Chloritoid is fairlycommon. Blue amphibole further field studies to unravelthe structural and shows a considerable peak in sample 239. stratigraphicrelationships of the blueschistsin the 4. KargiCay: schistose lithic fragments and micas are area. It is important to determine whether theserocks characteristic and are accompanied by some ferruginous are associated with the tectonically displaced units of grains, garnet, actinolite and tourmaline. Blue amphibole the Antalya nappe exposed in anarrow belt on the is present in minor amounts. 5. Avsallar:near to the mouth of theKargi Cay the northern flank of the Alanya massif, and also whether metamorphic rocks of the Alanya massif terminate on the they occur in the massif itself. The streams which flow coast and from there Miocene molasse facies rocks form through the Antalyan units show the highest content the coastal range.However, further inland there is a of blue amphibole. continuation of the metamorphic rocks with fragments of Thepresumed occurrence of glaucophaniticrocks the Antalya nappe on their northern margin. Sample 258 between Demirtas and Gazipasa, the locus of a ‘tec- reflects the considerable change in petrography and shows tonic window’ inthe Alanya massif, also has important a compositemineral spectrum: clinopyroxenes, such as tectonicimplications: ‘In the middle of theAlanya diopsidicaugite, titaniferous augite and acmitic augite, massif,in the region of Demirtas and Gazipasa, the hornblende, garnet, some kyanite,blue amphibole and clinozoisite. same formations’ (i.e. Antalyan complexes) ‘come out 6. Alara Cay-Manavgat:mineral assemblages reflecting ina tectonic window under the metamorphics’ (Ar- igneous as well as metamorphic provenance characterize gyriadis 1974).Abundant glaucophane in thesedi- the sediments. Ortho- and clinopyroxenes,olivine and ments indicates that high-pressure rocks are also pres- hornblende represent the igneous source, and garnet, an- ent in this complex tectonic setting. dalusite, kyaniteand chloritoid the metamorphic. Blue The blue amphiboles and associated minerals are of amphiboleoccurs in remarkable quantities and is espe- detrital origin, and the data are insufficient to assess cially abundant in samples 252 and 257 at the mouths of conditionsduring metamorphism. The twoblue am- the Alara and Karpuz Cay. Clinozoisite is common and a phibolesuites, however, indicate variable conditions number of grains are intergrown with blue amphibole. during their formation. Particularly interesting is the presence of remnants of Ca-amphiboles in the blue sodic amphiboles of the eastern unit, suggesting that Tectonic significance pressure increased during the period of metamorph- ism. This was not noted in the western area. Blue sodic amphibole is widespread in the sediments With regard to the origin of the blueschists, these of the southern Turkish coast between Gazipasa and mayoccur in ophiolite-blueschist mClanges or form Manavgat. Since thedetritus wasderived from the ‘exotic blocks’ tectonically inserted into the surround- metamorphic Alanya massif and adjacent areas to the ing formations. Thegenerally accepted hypothesis that N, glaucophanitic rocks must be present in this region. blueschists are confined to convergentlithospheric Rivers such as the Sedre Cay, Oba Cay, Alara Cay, plate boundaries, thus markingcollisional suture zones, Karpuz and Manavgat Irmagi, which are characterized is presumably applicable (Dewey et al. 1973; Dewey by abundant blue amphibole, obviously have outcrops 1974, 1976; Ernst 1971, 1972, 1973; Coleman 1971, of blueschists along their courses. 1972, 1977). The blue amphiboles of the eastern sector between According tothe latestinterpretation of the tec- GazipasaandDemirtas arehomogeneous and tonics of the eastern Mediterranean, it can be argued glaucophaniticin composition, whereas to the W of (Lapierre & Rocci 1976,Biju-Duval 1977; Brunn Alanya most of the blue amphibole is composed of 1976, 1979; Delaune-Mayere et al. 1977; Ricou et al. either crossitic glaucophane,crossite or rarely 1979) that the evolution of this area is characterized magnesio-riebeckite. Accompanying accessory miner- by the continental collision between the -Asiatic als such as clinozoisite and sphene emphasize the pro- andArabo-African plates and by the Maestrichtian vincialvariation of theblue amphiboles. Sphene is obduction of the radiolaritic-ophiolitic material on the more common in the eastern unit, whilst clinozoisite is African platform. This was followed by post-orogenic abundant in the western area. It can be assumed that (Miocene) remobilization of the various units and nap- conditions of paragenesis favoured the development of pes(Brunn 1976; Ricou et al. 1979;Sengor 1979). clinozoisite, while epidote remained subordinate andis Thishypothesis is consistentwith conditions which confined to the matrix. result in the formation of high-pressure rocks and the Chloritoid,according to Blumenthal(1951) and juxtaposition of rocks of different age and origin in the Peyronnet(1967, 1971) associatedis with the ‘Taurus occidental’. metamorphosedbauxite, found invarious locations Finally it is of interest that Argyriadis (1974) and betweenthe Dim Cay andAlara Cay.Chloritoid Ricou et al. (1974) emphasized the similarity between occursmore widelyin the area than waspreviously the Alanya massif and the Bolkar Dag metamorphic noted, in thesediments around Gazipasa, W from complexes. In the latter, Demirtasli et al. (1975) de- Alara Cay, and in the Manavgat river. scribedophiolitic milanges and ophioliticolistoliths, The sedimentologicalevidence clearly requires and van derKaaden (1966) and Bingo1 (1974)

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reported glaucophaniticrocks in various locations. The ACKNOWLEDGMENTS.This work was carried out during the blueschists associated with the Alanyamassif therefore tenure of a fellowship, awardedby Imperial College, which is probably formed part of a narrow discontinuous belt gratefullyacknowledged. I am indebted to Professor Janet of blueschists and allied metamowhics as well as Watson for proposing the subject as well as her stimulating ophiolites running from theBolkar through the suggestions; Dr Graham Ems and Dr RogerMason for theirhelpful comments; and to Mr R.Curtis and Mr N. upper Goksu river area as far as the Manavgat Wilkinsonfor their assistance in theX-ray and electron valley. analyses. microprobe

References

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Received 16 June 1980; revised typescript received 10 November 1980.

M. A. MANGE-RAETZKY, UniversitatBern, Geologisches Institut, 3012 Bern, Sahlistrasse 6. Switzerland.

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