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The age, emplacement, and metamorphic history of the garnet amphibolitic and retrogressed eclogitic slices in the Menderes Massif (Eastern Aegean) have been a matter of debate since the 1990’s. Late Cretaceous garnet amphibolitic and retrogressed eclogitic slices in the Bozdağ and Çine nappes show low-angle tectonic contacts with the surrounding Early Cambrian meta-siliciclastics in the Alaşehir-Yahyaalcı and late Neoproterozoic basement rocks in the Birgi and Tire-Çamlıca Klippe in the northern Menderes Massif. Lower and upper intercept ages on the discordia diagrams of the garnet amphibolitic slices are 82 ± 230 Ma and 554 ± 14 Ma, respectively, in the Yahyaalcı-Alaşehir area of the Bozdağ Nappe; and 96 ± 260 Ma and 550 ± 13 Ma, respectively, in the Camlica-Tire Klippe area of the Çine Nappe. Retrogressed eclogitic slices give dates of 81 ± 13 Ma lower intercept and 546 ± 13 Ma upper intercept discordant ages in the Yenişehir-Kiraz area of the Çine Nappe. Lower intercept age of 81 ± 13 Ma is supported by two spots dated on metamorphic zircons showing positive Eu patterns yielding 86.0 ± 1.3 Ma concordant age. Zircon U-Pb dating on the oscillatory zoning spots are dated as 537.5 ± 1.6 Ma (mean square weighted deviation [MSWD] = 1.5, n = 41) for the garnet amphibolic slices in the Yahyaalcı-Alaşehir area (Bozdağ Nappe), 539.0 ± 1.1 Ma (MSWD = 1.4, n = 56) for the garnet amphibolite slices in the Camlica-Tire Klippe area (Çine Nappe), and 536.6 ± 2.3 Ma (MSWD = 1.7, n = 32) for the retrogressed eclogitic slices (Çine Nappe). These ages combined with Eu negative anomalies on the dated spots are evaluated as representing their magmatic crystallization ages of the protoliths. Garnet isopleth intersections and pseudosections gave pressure-temperature conditions of 14 kbar and ∼680 °C for the retrogressed eclogites, whereas garnet amphibolites display disequilibrium in whole rock scale. We propose that the age of their protoliths likely correlate with the Cadomian rift-related Early Cambrian meta-mafic dykes that were subducted beneath the İzmir-Ankara-Erzincan Neotethyan lithosphere during the Late Cretaceous. The new rutile U-Pb age of 30.1 ± 2.0 Ma supports that the tectonic slices of the İzmir-Ankara oceanic lithosphere and metamorphosed Tauride-Anatolide continental margin were emplaced onto the Menderes Massif to generate the “main Menderes metamorphic terrane” during the latest Paleocene and early Eocene.

Geochemical data and Sr–Nd isotopes of the host rocks and magmatic microgranular enclaves (MMEs) collected from the Oligocene Nodoushan Plutonic Complex (NPC) in the central part of the Urumieh–Dokhtar Magmatic Belt (UDMB) were studied in order to better understand the magmatic and geodynamic evolution of the UDMB. New U–Pb zircon ages reveal that the NPC was assembled incrementally over ca. 5 m.y., during two main episodes at 30.52 ± 0.11 Ma and 30.06 ± 0.10 Ma in the early Oligocene (middle Rupelian) for dioritic and granite intrusives, and at 24.994 ± 0.037 Ma and 24.13 ± 0.19 Ma in the late Oligocene (latest Chattian) for granodioritic and diorite porphyry units, respectively. The spherical to ellipsoidal enclaves are composed of diorite to monzodiorite and minor gabbroic diorite (SiO2 = 47.73–57.36 wt.%; Mg# = 42.15–53.04); the host intrusions are mainly granite, granodiorite and diorite porphyry (SiO2 = 56.51–72.35 wt.%; Mg# = 26.29–50.86). All the samples used in this study have similar geochemical features, including enrichment in large ion lithophile elements (LILEs, e.g. Rb, Ba, Sr) and light rare earth elements (LREEs) relative to high field strength elements (HFSEs) and heavy rare earth elements (HREEs). These features, combined with a relative depletion in Nb, Ta, Ti and P, are characteristic of subduction-related magmas. Isotopic data for the host rocks display ISr = 0.705045–0.707959, εNd(t) = −3.23 to +3.80, and the Nd model ages (TDM) vary from 0.58 Ga to 1.37 Ga. Compared with the host rocks, the MMEs are relatively homogeneous in isotopic composition, with ISr ranging from 0.705513 to 0.707275 and εNd(t) from −1.46 to 4.62. The MMEs have TDM ranging from 0.49 Ga to 1.39 Ga. Geochemical and isotopic similarities between the MMEs and their host rocks demonstrate that the enclaves have mixed origins and were most probably formed by interactions between the lower crust- and mantle-derived magmas. Geochemical data, in combination with geodynamic evidence, suggest that a basic magma was derived from an enriched subcontinental lithospheric mantle (SCLM), presumably triggered by the influx of the hot asthenosphere. This magma then interacted with a crustal melt that originated from the dehydration melting of the mafic lower crust at deep crustal levels. Modeling based on Sr–Nd isotope data indicate that ∼50% to 90% of the lower crust-derived melt and ∼10% to 50% of the mantle-derived mafic magma were involved in the genesis of the early Oligocene magmas. In contrast, ∼45%–65% of the mantle-derived mafic magma were incorporated into the lower crust-derived magma (∼35%–55%) that generated the late Oligocene hybrid granitoid rocks. Early Oligocene granitoid rocks contain a higher proportion of crustal material compared to those that formed in the late Oligocene. It is reasonable to assume that lower crust and mantle interaction processes played a significant role in the genesis of these hybridgranitoid bodies, where melts undergoing fractional crystallization along with minor amounts of crustal assimilation could ascend to shallower crustal levels and generate a variety of rock types ranging from diorite to granite. Keywords: Urumieh–Dokhtar magmatic belt, Granitoid rocks, Subduction, Zircon U–Pb ages, Radiogenic isotopes, Central Iran

Archaeological burial contexts may include a variety of white substances, but few analyses have been published. This study reports on the physico‐chemical characterization of such residues from seven archaeological sites. It is often assumed that white materials from burial contexts are lime. Our findings demonstrate that they can be gypsum, calcite (chalk), aragonite, brushite, degraded metal, natural (gum) resins or synthetic polymer–based products. These may be present as the result of diagenetic processes, funerary practices or modern contamination. This paper provides an analytical approach for the holistic investigation of white materials encountered in burial contexts.

The study was performed in central-northern Anatolia (from Ankara to Amasya) to investigate the relationships of the Sakarya Zone units and the Izmir–Ankara–Erzincan suture (IAES) melange. It reveals that all the Sakarya Zone units are metamorphic and three main tectonostratigraphic units have been distinguished for the first time: the BAA (metasiliciclastic rocks capped by metacarbonates and varicoloured phyllite), the BKC (poly-metamorphic garnet-bearing micaschist and metabasite with a well-preserved relict HP–LT amphibole in a low-amphibolitic to greenschist-facies framework) and the AMC (meta-arkose passing vertically to carbonate–phyllitic alternations and, then, to a thick succession of prevailing acidic to intermediate–basic metavolcanites and volcanic-rich metasediments). The BAA and AMC, whose metamorphic frameworks are of Cimmerian age, underlie the Mesozoic carbonate cover sequences (e.g. t2-3, j3–k1) that often show tectonic detachments and slicing. The piling up of the BAA above the HP–LT BKC can be correlated to the tectonic superposition of two similar units (i.e. the Cimmerian Çangaldağ Complex and the Alpine Middle–Upper Cretaceous Domuzdağ Complex, respectively) defined by previous authors in other sectors of the Central Pontides front. The ophiolitic melange generally underlies the Sakarya Zone, but locally (e.g. SE of Amasya) tectonically rests above the latter, probably owing to back-thrusting that occurred during the Tertiary syn-collisional shortenings and the later strike-slip tectonics. We hypothesize that, also in these areas, the Sakarya Zone–IAES consists of a complex tectonic stack of different units, belonging to different palaeogeographic domains and orogenic events (Cimmerian versus Alpine orogenies), but originated within a single long-lived (since Late Triassic to Paleocene/Eocene times), prograding subduction–accretion system in front of the Laurasian continent.

The Oligocene Ghaleh Yaghmesh plutonic massif (GYPM) consists of diorite, quartz-diorite, tonalite and granodiorite and evolving from metaluminous nature. All the samples are predominantly medium-K calc-alkaline series, having typical characteristics of I-type granitoids. A significant geochemical criteria of the GYPM is the impoverishment of high-field-strength elements (HFSE) (e.i. Zr, Nb, Ti and Hf) and the overabundance of large-ion-lithophile elements (LILE) (e.i. K, Sr, U, Ba and Cs), with respect to the light rare elements (LREE) as compared to chondritic concentration. These geochemical criteria suggest the involvement of sedimentary components in the generation of rocks studied. Furthermore, variable Pb/Ce amounts, linear trend of all rocks studied on Ti/Zr vs. Yb/Hf diagram, as well as some characteristics petrographic features (e.i. acicular apatite, corroded margin of the plagioclases, the amphiboles and some of the pyroxenes, oscillatory zoning of plagioclases) and the presence of mafic microgranular enclave (MME) indicate that the Ghaleh Yaghmesh parental magma was likely generated by the partial melting of a mixed source dominantly composed of amphibolite and possibly meta-sedimentary source. The overall geochemical and petrographic features are consistent with the interpretation of the Urumieh–Dokhtar Magmatic Arc as an active continental margin during subduction of the Neo-Tethyan oceanic crust underneath the Central Iranian microcontinent.

In the Late Cretaceous, throughout the closure of the Neotethys Ocean, ophiolitic rocks from the Izmir–Ankara–Erzincan ocean branch were overthrusted the northern margin of the Tauride-Anatolide Platform. The ophiolitic rocks in the Ekecikdag (Aksaray/Central Turkey) region typify the oceanic crust of the Izmir–Ankara–Erzincan branch of Neotethys. The gabbros in the area are cut by copious plagiogranite dykes, and both rock units are intruded by mafic dykes. The plagiogranites are leucocratic, fine- to medium-grained calc-alkaline rocks characterized mainly by plagioclase and quartz, with minor amounts of biotite, hornblende and clinopyroxene, and accessory phases of zircon, titanite, apatite and opaque minerals. They are tonalite and trondhjemite in composition with high SiO2 (69.9–75.9 wt%) and exceptionally low K2O (

Cardiovascular disease (CVD) is one of the main causes of morbidity and mortality in chronic obstructive pulmonary disease (COPD) patients however data regarding left ventricle (LV) function in COPD is limited. We, in this study, aimed to evaluate the LV systolic function and its relation to BODE index in COPD patients with the utility of two-dimensional speckle tracking echocardiography (2D-STE). The study involved 125 COPD patients and 30 control subjects. All patients underwent 2D-echocardiography, pulmonary function tests and -minute walk tests. The patients were divided into four quartiles according to BODE index score. COPD patients had lower mitral annulus systolic velocity (Sm), average global longitudinal strain (GLS), average global longitudinal strain rate systolic (GLSRs), average GLSR early diastolic (GLSRe), average GLSR late diastolic (GLSRa), tricuspid annular plane systolic excursion (TAPSE) and peak systolic myocardial velocity (Sm-RV) (p0.001, p0.001, p0.001, p0.001, p0.001, p0.001 and p = 0.002 respectively) than control subjects. There were significant differences between BODE index quartiles in terms of Sm, average GLS and average GLSRs. Patients were divided into two groups according to median value of GLS (-18.6 and ≤ -18.6). BODE index quartiles were found to be independent predictors of decreased GLS in multivariate logistic regression analysis (p = 0.030). Increased BODE index was associated with impaired LV mechanics in patients with COPD.

Ekecikdag Magmatik Birligi (EMB), Orta Anadolu Kristalen Kompleksi’ndeki carpisma-carpisma sonrasi granitoyidlerdendir. Degisen oranlarda amfibol, biyotit, muskovit, plajiyoklaz, alkali-feldispat, kuvars ana mineralleri ve apatit, zirkon, titanit, manyetit aksesuar minerallerini iceren birlik granodiyorit, mikrogranit ve lokogranit bilesimli kayaclardan olusmaktadir. Ana granitik faz, mafik mikrogranuler anklav, iri K-feldispat kristali, bol biyotit ve amfibol (% 45-55) iceren faneritik porfiritik dokulu granodiyorittir. Koyu gri mikrogranuler mikrogranit ve orta-esit tane dokulu, % 5-15 mafik mineral iceren pembemsi beyaz lokogranit, iki mikali (biyotit+muskovit) granitoyidlerdir. Tum-kayac element verileri, granitoyidlerin kalk-alkalen, yuksek potasik, S- ve I-tipi karakterde olduklarini gostermektedir. Coklu element dagilim grafiklerinde negatif Ba, Nb, Sr, P, Eu, Ti anomalileri ve nadir toprak element (NTE) grafiklerinde hafif NTE zenginlesmesi karakteristiktir. La, Eu ve Ce negatif anomali gosterirken, Th, U ve Pb pozitif anomali gostermektedir. Lokogranit digerlerine gore dusuk hafif NTE ve yuksek agir NTE degerleri gostermektedir. Granodiyoritle mikrogranitin NTE dagilimlari, magma kaynaginda granatin / hornblendin birikmesini vermektedir. Kayaclardaki amfibol, biyotit, feldispat ve oksitlerin kimyasal bilesimleri petrolojik ozellikler ve yerlesim kosullarinin belirlenmesinde kullanilmistir. Granodiyoritte bulunan amfibol kalsik alt grubundan olup magnezyum-hornblend bilesimindedir. Uc kayac tipinde de bulunan biyotit Mg’ca zengin olup yuksek Fe3+/(Fe2++Fe3+) oranlarina sahiptir. Alkali-feldispat tum kayaclarda Or85-98 icerigiyle dar komposizyon araligi verirken, plajiyoklaz bilesimleri farklilik gostermektedir (granodiyorit: An15-49, mikrogranit: An17-62, lokogranit: An1-17). Oligoklaz tum kayac tiplerinde tanimlanmistir. Mineral kimyasi verileri, granodiyorit ve lokogranitin kalk-alkalen, mikrogranitin peraluminali karakteri ve granodiyoritin hibridik kokenini ortaya koymaktadir. Ayrica, kayaclarin farkli kokenlere sahip olup degisik oranlarda manto katkili(?) meta-magmatik ve meta-sedimenter kabuksal kaynaklardan turediklerine isaret etmektedir. Jeotermometrik hesaplamalar magmatikten sub-solidusa genis aralikta sicaklik (granodiyorit: 615-783°C, mikrogranit: 464- 565°C, lokogranit: 456-482°C) vermistir. Dusuk degerler, yavas soguma sirasinda gec evrede yeniden dengelenmeye isaret etmektedir. Jeobarometrik hesaplamalar, jeoloji ve mineral topluluklari yerlesim derinliginin orta kabuksal seviyelere karsilik geldigini ortaya koymaktadir (granodiyorit: 3-4.5 kbar / 10-16 km, mikrogranit-lokogranit: 3.3-3.6 kbar / 11-12 km). Oksijen fugasitesi yuksektir (HM-FMQ).

The Kurancali ultramafic-mafic cumulate body, an allochthonous ophiolitic sliver in central Anatolia, is characterized by the presence of abundant hydrous phases (phlogopite, pargasite) besides augitic diopside, plagioclase, and accessory amounts of rutile, sphene, apatite, zircon, and calcite. Based on modes of the essential minerals, the olivine-orthopyroxene-free cumulates are grouped as clinopyroxenite, hydrous clinopyroxenite, phlogopitite, hornblendite, layered gabbro, and diorite. Petrographical, mineralogical and geochemical features of the rocks infer crystallization from a hydrous magma having high-K calc-alkaline affinity with slightly alkaline character, and point to metasomatised mantle as the magma source. Our evidence implies that the metasomatising component, which modified the composition of the mantle wedge source rock in an intra-oceanic subduction zone, was a H2O, alkali and carbonate-rich aluminosilicate fluid and/or melt, probably derived from a subducted slab. We suggest that the metasomatic agents in the subarc mantle led to the generation of a hydrous magma, which produced the Kurancali cumulates in an island-arc basement in a supra-subduction-zone setting during the closure of the Izmir-Ankara-Erzincan branch of the Alpine Neotethys Ocean.

Dioctahedral vermiculite occurs in an isolated metagabbro klippe (Kurancali Metagabbro) that belongs to the Central Anatolian Ophiolites from central Turkey. Both the metagabbro and the structurally underlying high-grade metamorphic rocks are intruded by granitic rocks. The Kurancali Metagabbro is characterized by its well-developed compositional layering, and the presence of vermiculitized phlogopite-rich layers. Petrographic and mineralogic studies show that the primary mineral phases in the host rock are diopside, tschermakitic hornblende, Fe-rich phlogopite, and plagioclase. Secondary minerals are hornblende, actinolitic hornblende, Fe-rich phlogopite, and vermiculite. A two-phase history of alteration involving acidic weathering and alkaline metasomatism is suggested for the dioctahedral vermiculite and secondary Fe-rich phlogopite, respectively. The alteration of phlogopite to dioctahedral vermiculite proceeded both along cleavage planes and at crystal edges. The vermiculite is colorless to pale yellow with weak pleochroism and shows optical continuity with the parent mineral. Vermiculite flakes, analyzed semi-quantitatively by scanning electron microscope-energy dispersive analysis (SEM-EDS) and electron microprobe (EMP), are characterized by partially expanded interlayers, K depletion, and Mg and/or Al enrichment. X-ray diffraction (XRD) and differential thermal analysis-thermal gravimetric (DTA-TG) analyses indicate that phlogopite is not a pure phase, although it is the dominant one. The XRD patterns show the presence of both dioctahedral vermiculite having dehydrated interlayers and hydroxy-Al interlayers, and interstratified phlogopite-vermiculite. The transformation of phlogopite to vermiculite is thought to represent an initial stage of weathering in an acidic environment.

The Late Cretaceous granitic rocks within central Anatolia (Turkey) not only date and show the magmatic aspects of the Alpine realm, but also give clues about its geodynamic character. Among them, the Satansari monzonite stock (SMS), part of the Terlemez pluton (Aksaray), characterizing the inception of an extensional tectonic regime in central Anatolia, has a subalkaline, metaluminous and magnesian geochemical nature with depletion in Ba, Nb, P and Ti, and with enrichment of Th, U, K and Pb relative to primitive mantle. The SMS has LREE enriched patterns ([La/Yb]N = 18.45–21.21) with moderately negative Eu-anomalies ([Eu/Eu*]N = 0.65–0.73). The geochemical data infer a crustal source with an inherited subduction-related component, and fractionation of plagioclase and amphibole. A crustal signature for the SMS is also inferred from high 87Sr/86Sr(t) ratios (0.70826–0.70917), and low ɛNd(t) values (−6.9 to −7.6). Zircon crystals from the SMS typically have magmatic rims overgrowing inherited cores that are reworked, resorbed and overgrown. Completely new zircon crystals grown in a single magmatic episode have also been identified. Laser ablation ICP-MS U–Pb zircon analyses yield a mean 206Pb/238U age of 74.4 ± 0.6 Ma (2σ) for the intrusion of the SMS. Rare discordant analyses range from the Devonian to the Proterozoic (i.e., 207Pb/206Pb ages between 364 Ma and 1263 Ma). In situ zircon Hf isotope analyses reveal low 176Lu/177Hf ratios and negative ɛHf(t) values, which is consistent with a predominantly crustal source of the SMS. We suggest that the water-rich magmas were generated in a hot zone within the crust produced by residual melts from basalt crystallization and partial melts of pre-existing metamorphic and igneous rocks within the lower crust of central Anatolia. The SMS likely formed by episodic injections of these hybrid monzonite melts by adiabatic ascent to shallow crust where they crystallized. This interpretation may be useful in interpreting the involvement of crustal sources for other monzonitic rocks in central Anatolia and granitic magmatism in other similar tectonic environments.

Summary The external zircon morphology of granitoid rocks is combined with internal structures studied by cathodoluminescence imaging, to test the classic ‘Pupin method’ against geological and geochemical evidence for the origin and evolution of granitic rocks. Granitoids in Central Anatolia display a wide range of petrological characteristics from S-type and I-type to A-type. We studied the morphologies and internal structures of zircons from the Terlemez, Baranadag, C amsari and the Hisarkaya granitoids from Central Anatolia. The Terlemez and Baranadag quartz-monzonites show a hybridized I-type nature regarding the mineralogy and geochemistry, while the C amsari quartzsyenite is a typical A-type granitoid. The Hisarkaya porphyritic granite shows fractionated I-type geochemical characteristics, but has significant crustal involvement in its source. In these granitoids, zircon is associated with biotite, quartz, orthoclase, plagioclase, and allanite. Typological investigations after Pupin (1980) along with scanning electron microscope imaging reveal that the external morphology of zircon varies consistently with the granitoid type. Zircon populations of the I-type Terlemez and

The last stages of the continental collision during the closure of the Neotethyan ocean in central Anatolia are characterized by post-collisional H- and A-type granitoids intruding both the metamorphic country rocks and allochthonous ophiolitic rocks of the central Anatolian crystalline complex. Available Rb–Sr and K–Ar whole-rock and mineral age data on the H- and A-type granitoids in central Anatolia are inconsistent. To better constrain the geological relevance and the timing of the change in the chemical character of magmatism in the wake of the Alpine orogeny in Anatolia, we re-evaluated the geochemical characteristics and dated titanite from representative H- (Baranadag quartz-monzonite: BR) and A-type (Camsari quartz-syenite: CS) granitoids by the U–Pb method. BR is a high-K calc-alkaline intrusion with mafic microgranular enclaves and shows enrichment of LILE relative to HFSE. The alkaline CS displays higher SiO2, Na2O+K2O, Fe/Mg, Rb, Th and HFSE with corresponding depletion in CaO, MgO, Fe2O3tot, P2O5, Ba, Sr, and Ti. Chondrite-normalized REE patterns of the BR and CS samples have LREE-enriched and flat HREE patterns, whereas CS differs from BR by higher LREE enrichment and lower MREE and HREE contents. Mineralogical and geochemical characteristics suggest that BR and CS were not products of the same magma source. BR was derived from a subduction-modified depleted hybrid-source and CS had an enriched mantle source with significant crustal contribution. The U–Pb titanite ages of the H-type central Anatolian granitoids (BR) and the A-type granitoids (CS) are 74.0±2.8 and 74.1±0.7 Ma, respectively. The coeval evolution of post-collisional/calc-alkaline H- to A-type magmatism was possibly associated with source heterogeneity and variable involvement of continental materials during the evolution of these granitoids. These new age data constrain the timing of the onset of a post-collision extensional period following the Alpine thickening within the passive margin of the Tauride–Anatolide platform, which occurred before the opening of the latest Cretaceous central Anatolian basins.

[Paquette and Le Pennec (2012)][1] presented new zircon U-Pb age data from the ignimbrites in Central Anatolia and determined them as Neogene, while they also detected zircons revealing Paleo-Proterozoic to Archean U-Pb ages (ranging from 2.3 to 3.8 Ga). Their explanation for this circumstance is

The Kurancali metagabbro occurs as an isolated body in the central part of the Central Anatolian Crystalline Complex. It has been emplaced along a steep S-vergent thrust-plane onto the uppermost units of the Central Anatolian Metamorphics. The main body of the Kurancali metagabbro is characterized by distinct compositional layering. The layered gabbros comprise pyroxene and hornblende gabbros. Phlogopite-rich, plagioclase-hornblende gabbro occurs mainly as pegmatitic dikes intruding the layered gabbro sequence. The layered gabbros, in general, consist mainly of diopsidic augites, brown hornblendes, and plagioclase. Secondary phases are phlogopitic mica, brownish-green hornblende replacing clinopyroxenes, and fibrous, greenish actinolitic hornblende partially or completely replacing brown hornblende. The primary dark micas are phlogopitic in the range of phlogopite(57-70) and annite(30-43). The analyzed pyroxenes are diopsidic (En32Fs19Wo49-En35Fs18Wo48). The whole-rock geochemistry of the gabbros indicate...

Bu çalışmanın amacı, Biga Yarımadası'ndaki analsim içeren tüflerin jeolojik, petrografik, mineralojik ve jeokimyasal özeliklerini anlamak ve oluşum modellerini ortaya koymaktır.Ayvacık-Küçükkuyu arasında bulunan çalışma alanı beş farklı birim içerir. Bunlar Eosen öncesi metamorfik temel, Behram Volkanikleri (Arıklı Tüfü, andesit, andesitik aglomera), Pliyosen Volkanikleri, Miyosen gölsel çökelleri ve Kuvaterner alüvyonudur. Arıklı Tüfü'nün içinde bulunan analcime bu çalışmanın asıl amacını oluşturmaktadır.Arıklı Tüfü'ne uygulanan detaylı petrografik ve mineralojik çalışmalar X-ışınları difraktometresi, optik mikroskop, elektron mikroskobu, diferansiyel termal metod ve jeokimyasal çalışmalar ile yürütülmüştür.Arıklı Tüfü'nün içinde bulunan ince ve kalın taneli analsim kristalleri renksiz, izotrop, trapezohedral şekil ve düşük rölyef özellikleri ile saptanmıştır. Petrografik çalışmalara ek olarak SEM ve XRD çalışmaları ile de analsim varlığı teyit edilmiştir.Petrografik ve mineralojik çalışmalar ile iki oluşum şekli saptanmıştır; boşluklarda ya da pümisin içinde kalın taneli özşekilli ya da yarı özşekilli kristaller ve hamurun içinde gömülü olan tek ya da küme halinde bulunan kristallerdir.Petrografik ve SEM çalışmalarının ışığı altında iki adet oluşum tipi belirlenmiştir. Bunlar volcanic camdan alterasyon ile oluşma ve alkali sulardan çökelme ile oluşum şeklidir. Jeokimyasal metodlar bu oluşum modellerini desteklemektedir. The purpose of this study is to understand the geological, petrographical, mineralogical and geochemical characteristics of analcime-bearing tuffs in the Biga Peninsula and to determine formation process of these tuffs.The study area lies between Ayvacık and Küçükkuyu. The rock units are pre-Eocene basement rocks, Miocene Behram Volcanics (Arıklı Tuff, andesite, andesitic agglomerate), Pliocene volcanics, Miocene lacustrine sediments (Küçükkuyu Formation) and Quaternary alluvium. Analcimes which are found in Arıklı Tuff are the main objective of this study.Detailed petrographical, mineralogical and geochemical studies were caried out on the Arıklı Tuff samples by using petrographical microscope, X-ray diffractometry, scanning electron microscopy, diffrential thermal analyses inductively coupled plasma ? mass spectrometry and optical emission spectrometry.Fine-grained and coarse-grained analcime crystals in Arıklı Tuff were determined by their colorless, isotropic, trapezohedral and low relief. In addition to petrographic study, SEM and XRD methods also confirmed the presence of analcime.Two modes of occurrences were determined by the petrographical and mineralogical studies; coarse-grained euhedral or anhedral crystals in cavities and pumice fragments and single crystals or clusters of fine-grained analcimes embedded in the matrix.It was stated that there are two types of formation of analcime; alteration of volcanic glass and precipitation from alkaline solution based on petrographical and SEM studies. Geochemical methods, moreover, support the formation types. 210