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Heavy mineral contents of Tuzla Stream delta dunes (Gülpinar?Çanakkale) and their origin
Get PDFFen Bilimleri Enstitüsü, Jeoloji Mühendisliği Ana Bilim DalıÇalışma alanı, Biga Yarımadası'nın (KB Türkiye) güneybatı kısmında yer almaktadır ve yaklaşık 650 km2 lik bir alanı kapsar. Bu çalışma, Tuzla Çayı'nın güncel sedimanlarındaki ağır mineralleri tanımlamayı ve sedimanların beslenme havzası içindeki ana kayalar ile ilişkisinin ortaya konulmasını amaçlamaktadır.Çalışma alanının temelini Kazdağ Grubu'na ait granitik gnays, amfibolit, mika şist ve mermer mercekleri içeren yüksek dereceli metamorfik kayalar oluşturmaktadır. Kazdağ Grubu kayaları üzerine, düşük dereceli metamorfizma geçirmiş Çamlıca metamorfitleri gelmektedir. Granat mika şist ve eklojitten oluşan ?Elliayak eklojiti? tektonik dilim halinde yine Kazdağ Grubu üzerine gelmektedir. Ayrıca, aşırı derecede deforme Çetmi melanjı, tektonik bir dokanakla Kazdağ metamorfitleri üzerinde yer alır. Oligo-Miyosen yaşlı Evciler plütonu Kazdağ Metamorfitlerini keserek yerleşmiştir. Aynı dönem volkanizmasını temsil eden Alt-Orta Miyosen yaşlı Doyran-Ezine volkanitleri ise çalışma alanında geniş yüzlekler vermektedir.Çalışma alanının Neojen çökel birimleri, volkanik katkılı kumtaşı şeyllerden oluşan Küçükkuyu formasyonu ile konglomera kumtaşı, çamurtaşlarından oluşan İlyasbaşı formasyonu ve bunlarla uyumsuz olarak bulunan Kirazlı, Bayramiç ve Gülpınar formasyonlarıdır. Miyosen ve Pliyosen yaşlı bu formasyonlar genel olarak kırıntılılardan, gölsel karbonatlardan ve sığ denizel kireçtaşlarından oluşurlar. Kuvaterner yaşlı alüvyon, inceleme alandaki tüm birimlerden türeme çakıl, kum, silt ve killerden oluşur. Genellikle Tuzla çayı boyunca ve Tuzla deltasını oluşturan düzlük alanlarda görülmektedir.Tuzla deltasını oluşturan Tuzla Çayı Kazdağları'ndan doğmakta ve Ege Denizine dökülmektedir. Tuzla Çayı'nın uzunluğu yaklaşık 52 km dir. Bu çalışmada, Tuzla Çayı ve beslenme havzası dahilinde tüm kollarından sistematik sediman örneklemesi yapılmış, ağır minerallerin kaynak kayası olarak düşünülen beslenme havzası içerisinde kalan çevre kayalardan da örneklemeler yapılarak kaynak kaya mineralojisi ortaya konulmuştur.Kaynak kaya belirlenmesinde yararlanılan ağır minerallerden, rutil, turmalin, zirkon, granat, disten, epidot, sfen, amfibol, manyetit, ilmenit, pirit, hematit, olivin, zoisit, kayaç yapıcı minerallerden plajioklas, kuvars, biyotit, hornblend minerallerine yaygın olarak bulunmuştur.Elde edilen zirkon görüntülerinden, özşekilli zirkonlar ile yuvarlak zirkonların kaynak kayalarının Kazdağ Metamorfitleri ile Küçükkuyu Formasyonu olabileceği; olivin, epidot ve piroksen minerallerinin ise Çetmi Melanjı içerisindeki serpantinitleşmiş ultrabazik ve bazik kayalardan geldiği belirlenmiştir.The study area is located within southwestern part of Biga Peninsula, NW Turkey and covers an area of approximately 650 km2. In this study, focus will be given to the heavy mineral descriptions of current sediments of Tuzla Creek and relationships between these current sediments and host rocks into the catchment area.The basement of the study area is made up high grade metamorphic rocks (granitic gneiss-amphibolite-mica schist and marble lenses) of Kazdağ Group. Low grade metamorphosed Çamlıca Metamorphics overlie Kazdağ Group, Elliayak eclogite, consisting of garnet mica schist and eclogite, also overlies Kazdağ Group as tectonic slice. In addition, strongly deformed Çetmi Melange overlies Kazdağ Group with a tectonic contact. Kazdag metamorphic rocks are cut by Oligo-Miocene aged Evciler Pluton. Early-Middle Miocene aged Doyran-Ezine volcanites that represent the equal period volcanism, has a wide distribution in study area.Neogene deposits of the study area are represented by Küçükkuyu formation which is consist of sandstone and shales intercalated with volcanic rocks and İlyasbaşı formation which included conglomerate, sandstone and mudstone situated unconformably with Kirazlı, Bayramiç and Gülpınar formations. Miocene and Pliocene aged these formations are generally consist of clastics, lacustrine carbonates and shallow marine limestones. All units in the study area are overlain with unconformably by Quaternary alluvium deposits which included pebble, sand, silt and clay. Alluvium is generally seen along the Tuzla Creek and in the floors which forms Tuzla delta.Tuzla Creek which forms Tuzla delta comes from Kazdag and it pours out Aegean Sea. The length of Tuzla Creek is nearly 52 km. In this study, systematic sediment sampling is made in Tuzla Creek, catchment area, its all branches and the rocks that interpreted as a source rock of heavy minerals in the catchment area. Source rock minerology is tried to be explained with the samplings of surrounding rocks which are found in the catchment area.Heavy minerals such as rutile, turmaline, zircon, garnet, disten, epidote, sfen, amphibole, magnetite, ilmenite, pyrite, hematite, olivine, zoisite and rock forming minerals such as plagioclase, quartz, biotite, hornblend that useful for determination of the source rock have been found.The zircon images that obtained, the source rocks of euhedral zircons and rounded zircons can be Kazdag Metamorphites and Küçükkuyu Formation; serpentinized ultrabasic and basic rocks of Çetmi Melange are the source rocks of olivine, epidote and pyroxene minerals
The petrographical and geological investigation of the magmatic rocks in southeast Etili, Çanakkale
Get PDFFen Bilimleri Enstitüsü, Jeoloji Mühendisliği Ana Bilim DalıÇalışma alanı Kuzeybatı Anadolu'da, Biga Yarımadası'nda Kazdağ yükseliminin kuzeyinde kalan Etili ve çevresini kapsayan yaklaşık 154 km2 bir alandan oluşmaktadır. Bu çalışmada Etili beldesi ve güneyinde yer alan magmatik kayaların jeolojik konumları ile petrografik ve jeokimyasal özellikleri araştırılmıştır. Çalışma alanında temeli, Üst Kretase yaşlı serpantinit, kireçtaşı ve metaşeylden oluşan Çetmi Ofiyolit Melanjı oluşturur. Üst Oligosen-Alt Miyosen yaşlı Evciler Plütonu, Çetmi Ofiyolit Melanjı'nı keser. Bu plütonizma ile kökensel ilişkili olan lav, aglomera ve riyolitik tüften oluşan Çan volkanitleri bu birimleri uyumsuz olarak üzerler. Kumtaşı, silttaşı ve organik çamurtaşından oluşan Alt Miyosen yaşlı Küçükkuyu Formasyonu'na ait gölsel sedimanlar Çan volkanitleri ile arakatkılıdır. Kiltaşı, kumtaşı, kömür, organik şeyl, aglomera ve tüf stratigrafisi sunan Erken-Orta Miyosen yaşlı Çan Formasyonu, yaygın olarak gözlenen volkanik kayaçların üzerine uyumsuz olarak gelmektedir. Kuvaterner yaşlı birimler ise tüm birimleri uyumsuz olarak örterler. Çalışma alanındaki plütonik kayaçlar petrografik çalışmalar doğrultusunda granit granodiyorit ve kuvars diyorit bileşimlidirler. Çoğunlukla granüler ve porfiritik dokulu olup, plajioklas, K-feldispat, amfibol (hornblend), biyotit ve kuvars mineralerini içermektedirler. Volkanik kayaçlar ise çoğunlukla andezit olmakla birlikte, ender olarak dasit ve trakiandezit bileşimler sergiler. Plütonik ve volkanik kayaçların SiO2 ? Na2O+K2O değişim diyagramlarında subalkali alanda yer aldıkları görülür. Na2O+K2O - FeO - MgO (AFM) üçgen diyagramında ise magmatik kayaçlara ait örneklerin çoğu kalkalkalen alanda bulunmakta ve kalkalkalen trend göstermektedir. Çalışma alanındaki plütonik ve volkanik kayaların majör element, iz element ve nadir toprak elementleri sonuçlarına dayanarak, bu kayaçların oluşumunda fraksiyonel kristalleşmenin yanı sıra kabuksal kirlenme gibi magma karışım süreçlerinin de etkili olduğu belirtilebilir. Çalışma alanındaki yapısal unsurlardan Çan-Etili Fayı, Neotektonik dönem yapısı olup sağ yanal atımlı DKD-BGB doğrultuludur. Bu fay sistemine dik gelişen çizgisellikler muhtemelen volkanizma sırasında ya da neotektonik dönem içinde gelişmiş olmalıdır. Anahtar sözcükler: Etili, Petrografi, Jeokimya, Biga Yarımadası Hazırlanan bu Yüksek Lisans tezi ÇOMÜ Bilimsel Araştırma Projesi (BAP) tarafından 2007/08 no'lu projeden desteklenmiştirThe study area formed around 154 km2 that comprised Etili and its surrounding area, in the north of Kazdağ mountain range, Biga Peninsula, NW Anatolia. At the basement of the study area, represented by Late Cretaceous aged Çetmi Ophiolite Melange which consisted serpentinite, limestone, shale. Late Oligocene- Late Miocene aged Evciler Pluton cuts Çetmi Ophiolite Melange. These units are overlain uncomformably by the Çan volcanics, consisting of lavas, agglomerates and rhyolite tuffs. Lower Miocene age Küçükkuyu Formation including of sandstone, siltstone and organic mudstone related to lacustrine sediments interclated Çan volcanits. Volcanic rocks observed commonly in the study area are overlain with disconformity by Lower ? Middle Miocene aged Çan Formation showed stratigraphy claystone, sandstone, coal, organic shale, agglomerates and tüff. All units in the study area are overlain with unconformity by Quaternary alluvium deposits. Plutonic rocks in the study area have granite, granitoid and quartz diorite compositions. It has usually granular and porphyritic textures and consist of plagioclase, K-feldspar, amphibole (hornblende) biotite and quartz minerals. In the SiO2-Na2O+K2O diagram they show granite, granodiorite and quartz diorite compositions. Volcanic rocks show different composition ranging from andesite, trachyandesite, and dacite compositions. Plutonic and volcanic rocks in variation diagrams fall into subalkaline area. Na2O+K2O - FeO ? MgO (AFM) ternary diagram most of the samples indicate calc-alkalen trend. Results of major elements, trace elements and rare earth elements of plutonic and volcanic rocks can be related to fractional crystallization as well as magma mixing processes and crustal contamination. In the study area Çan-Etili fault is a dextral fault which has ENE-WSW strike. Linears developing vertical to this fault system are probably during volcanism or neotectonic period. Keywords: Etili, Petrography, Geochemistry, Biga Peninsul
Chrono-stratigraphic position of eocene, oligo-miocene volcanics around dededağ (Beyçayir-Çanakkale) and their importance for regional volcanism in the Biga Peninsula
No full textBu çalışmada, Biga Yarımadası'nda Lapseki ilçesi güneydoğusunda Dededağ ve çevresinde geniş alanlarda mostra veren farklı evrelerde oluşmuş magmatik kayaların volkano-stratigrafik konumunun ve petrolojik özelliklerinin aydınlatılması amaçlanmaktadır. Bölgede 40Ar/39Ar yöntemi kullanılarak elde edilen yaş verileri ile, 42 My'dan (Geç Eosen) 29 My'a (Erken Oligosen) kadar olan dönemdeki magmatik üniteler; litostratigrafik ve krono-stratigrafik olarak 6 farklı birime ayrılabilmektedir. Eosen döneminde ortaç karakterli, kalkalkalen Laledağ intrüzifi (granodiyorit) ve Beyçayır volkanitleri (andezit, dasit) ile alkalen ve bazik karakterli Kızıldam volkanitleri (bazaltik trakiandezit, trakibazalt) gelişmiştir. Oligosen döneminde ise asidik-ortaç, kalkalkali nitelikli dasit ve riyolit bileşimli Dededağ volkanitleri ile başlayan volkanizma, bazalt ve bazaltik andezit bileşimli Kırcalar volkanitleri ve bazalttan riyolite kadar değişen Harmancık volkanitleri ile devam etmiştir. Çamyayla plütonu bölgedeki Oligosen volkanitlerini keserek yerleşmiştir. Bölgedeki alkalen lavlar yüksek K'lu ve şoşonitik olarak sınıflanırken, kalkalkalen lavlar orta-yüksek K'ludurlar. N-tipi MORB ve kondrite göre normalize edilmiş iz element değişim diyagramlarında ise, tüm volkanik birimlerde, büyük iyon yarıçaplı litofil elementler (LILE) ve hafif nadir toprak elementler (LREE) bakımından zenginleşme, yüksek alan enerjili elementler (HFSE) ve ağır nadir toprak elementler (HREE) bakımından tüketilme görülmüştür. Bu durum yitim bileşeni ile zenginleşmiş, manto kaynak alanından türeyen lavlara benzerlik gösterir. Jeokimyasal veriler ile bölgedeki tüm volkanik kayaçların, fraksiyonel kristallenme, magma karışımı/tazelenmesi, kontaminasyon/asimilasyon süreçleri sonucunda farklılaştıkları anlaşılmaktadır. Sonuç olarak; çalışma alanında yüzeyleyen volkanik birimlerin Paleosen-Eosen döneminde kuzeyde Sakarya kıtası ve güneyde Anatolid-Torid kıtalarının çarpışmasını takip eden sıkışma ve gerilme rejimlerinin etkisi ile daha önceden yitim bileşeni ile zenginleşmiş litosferik manto kaynağından türemiş olabileceği düşünülmektedir.In this study, we aimed to clarify volcano-stratigraphic positions and petrological characteristics of igneous rock outcrops for large areas formed at different stages that are located at Dededağ and around in the southeast of the Lapseki town in the Biga Peninsula. In the region, magmatic units can be classified into 6 different groups by the lithostratigraphic and chonorostratigraphic data using 40Ar/39Ar methods (Eocene-Early Oligocene, 42.08±0.09 to 29.02±0.29 Ma). In Eocene period, there are calc-alkaline Laledağ granodiorite and Beyçayır volcanics with andesite, dacite composition that are the intermediate character, and also Kızıldam volcanics in characters of alkaline and basic character (basaltic trachyandesite, trachybasalt). Furthermore, in Oligocene period, the calc-alkaline volcanism starting with Dededağ volcanics with dacite and rhyolite composition in acidic-intermediate character, has continued with Kırcalar volcanics consisting of basalt and basaltic andesite, and Harmancık volcanics ranging from basalt to rhyolite. Çamyayla Pluton is intruded to Oligocene volcanics in the region. Alkaline lavas in the region are classified as high K and shoshonitic and calc-alkaline lavas have medium- high-K. In N-type MORB and chondrite-normalized trace element diagrams, the enrichment for all volcanic units was observed with regard to large ion lithophile elements (LILE) and light rare earth elements (LREE), the depletion for all volcanic units was observed with regard to high field strength elements (HFSE) and heavy rare earth elements (HREE). This situation shows similarity with an evolved source from mantle area that is enriched by subduction component. Using geochemical data, it is understood that all the volcanic rocks differentiated as a result of magma mixing/replenishment, contamination/assimilation process. Consequently, the source of volcanism is thought to be derived from compressional regime associated with the collision during the Eocene-Oligocene, and from previously enriched lithospheric mantle source with subsequent effects of extensional regimes
Geology of Neogene basins of Buldan-Sarıcaova region and their importance in Western Anatolia neotectonics
Get PDFThe Buyuk Menderes and Gediz (AlaAYehir) grabens are two significant segments of the Western Anatolian extensional province. They merge around Buldan-SarA +/- caova in the east. Outcropping Neogene sedimentary units in this area display a rather complex structure. This paper summarizes the importance and meaning of the data obtained during a detailed investigation of the Neogene units and aims to improve our understanding of the neotectonic evolution of Western Anatolia. The Buldan-SarA +/- caova Neogene sequence is composed of three different sedimentary units: (1) the Lower Unit, (2) the Middle Unit, and (3) the Upper Unit. The Lower Unit crops out on the Buldan horst which is located between the Buyuk Menderes and AlaAYehir grabens. The sequence starts as a coarse conglomerate and sandstone (A degrees salar Formation) and continues as lagoonal-lacustrine mudstone, interbedded with coal seams and shales (Bostanyeri Formation) and also with lacustrine limestones. The age of this succession is Lower-Middle Miocene. The development of the basin is structurally controlled by NNW-trending normal faults. The Middle Unit begins with a conglomerate-mudstone sequence (KA +/- zA +/- lburun Formation), followed by a sandstone-mudstone-marl sequence (Saraykoy Formation). A lacustrine limestone-marl unit occurs at the top (Aktepe Formation). Some thin gypsum lenses and layers are observed in the Saraykoy Formation. The unit contains some brackish-water fossils. The rocks of the Middle Unit crop out mostly at the low altitudes of the Buldan horst, i.e. the southeast piedmont, around the junction of the Buyuk Menderes and the Gediz grabens. The Middle Unit was deposited in fluvial and lacustrine environments during the Late Miocene-Pliocene period. These rocks were formed in response to the uplift of the Buldan horst. The Upper Unit, which is composed of conglomerates, was deposited within the Buyuk Menderes Graben-Gediz Graben depressions as alluvial fill.Turkish Petroleum Corporation (TPAO)The author is deeply indepted to Prof. Yucel Yilmaz for his guidance and help throughout this research. This study was supported by the Turkish Petroleum Corporation (TPAO). The author sincerely thanks Prof. Erdinc Yigitbas, and Prof. Dogan Perincek for their helpful reviews. I am also grateful to Prof. B. Clark Burchfiel for valuable and constructive comments and contributions. Catherine Yig. it is thanked for proof reading
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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