The Miocene – Pliocene boundary and the Messinian Salinity Crisis in the easternmost Mediterranean: insights from the Hatay Graben (Southern Turkey).

The Hatay Graben is one of three easternmost basins in the Mediterranean that preserve sediments that span the Miocene-Pliocene boundary, including gypsums from the Messinian Salinity Crisis (MSC). Here we integrate existing data and present new sedimentological and micropalaeontological data to investigate the palaeoenvironments of late Miocene to early Pliocene deposits and place this important area into a regional stratigraphic framework. Six sections are described along a ~ W – E transect illustrating the key features of this time period. Late Miocene (Pre-MSC) sediments are characterised by open marine marls with a benthic foraminiferal fauna suggestive of water depths of 100 – 200 m or less. Primary lower gypsum deposits are determined to be absent from the graben as sedimentological and strontium isotopes are characteristic of the resedimented lower gypsums. The intervening Messinian erosion surface is preserved near the basin margins as an unconformity but appears to be a correlative conformity in the basin depocentre. No Upper Gypsums or ‘Lago–Mare’ facies have been identified but available data do tentatively suggest a return to marine conditions in the basin prior to the Zanclean boundary. Sediments stratigraphically overlying the Messinian gypsums and marls are coarse-grained sandstones from coastal and Gilbert-type delta depositional environments. The Hatay Graben is not only strikingly similar to Messinian basins on nearby Cyprus but also to the overall model for the MSC, demonstrating the remarkable consistency of palaeoenvironments found in marginal basins across the region at this time

Micropaleontology and paleoecology of the Neogene sediments in the Adana Basin (South of Turkey)

This paper analyses the stratigraphical features and fossil associations (ostracod and planktonic foraminifer) of the late Miocene deposits in the Adana Basin. In this research, numerous samples were collected from the sediments, both below and above the Messinian evaporitic layers which cropped out in the western and middle part of the Adana Basin, due to paleoenvironmental changes during the Messinian salinity crisis. The fine-grained sediments below the gypsum layers surrounding Topçu and Karayayla villages located in the western part of the Basin are sterile. Nodular anhydrite and enterolithic structures are well developed in these selenitic gypsum layers, which are supposed to represent a sabkha environmental condition. In the middle part of the Adana Basin, some re-sediment detritic gypsum deposits cropped out around Semiramis village houses. The lithological characteristics and faunal assemblages of the sediments both below and above these evaporites are more or less similar to each other. Fossil fauna (ostracod and planktonic foraminifera) demonstrate that these sediments are not older than latest Tortonian, as suggested by the presence of Neogloboquadrina humerosa, and not younger than earliest Messinian, as suggested by the last occurrence of Globigerinoides bulloideus. Similar planktonic assemblages were found in the drill log bored east of the Adana Basin, where there was no evaporitic occurrence. Both the planktonic species and the presence of Globorotalia suterae (from 7.81. Ma to 7.24. Ma) point that also these fine granied sediments a late Tortonian-early Messinian in age. The quantity of kaolinite recorded is relatively higher in the Tortonian-early Messinian than in the late Messinian sediments. All data show that, during the latest Tortonian-earliest Messinian time interval, the area was characterised by shallow marine environments and humid climatic conditions. © 2010 Elsevier Ltd.FBE 98/21The authors are grateful for the financial support provided by TUBITAK (The Scientific and Technical Research Council of Turkey) and the Research Fund of Çukurova University Grant FBE 98/21. The authors are thankful the Turkish Petroleum Corporation for support of drill log samples in the study area They thank Prof. Dr. Kemal Gürbüz (Çukurova University) for his support during the field studies, and Prof. Dr. Hayriye İbrikçi (Çukurova University) for her critical reading and very useful comments and many thanks to both the reviewers and those in the editorial service for their critiques and suggestions

Tectono-stratigraphical position of Alacık formation (Lates Eocene - Early Miocene) in the Kahramanmaraş basin

Alacık formasyonu, Tersiyer öncesi sıkıştırma rejimi ve Miyosen sonrası gelişen doğrultu atımlı fay tektoniği arasında geçiş döneminde çökelmiştir. Bu formasyon, Kahramanmaraş Havzasının kuzeyinde, çok farklı litolojik özellik göstermektedir. Birim; Çukurhisar köyü (Kahramanmaraş kuzeybatısı) civarında, tabanda kumtaşı - çakıltaşlarıyla başlar, kiltaşları ile devam eder ve laminalı kiltaşları içinde en geç Orta Eosen-Geç Eosen yaşını veren iri bentik foraminiferli, ekstraklastlı karbonat yığışımları ile son bulur. Alacık formasyonu Tekir kasabası (Kahramanmaraş kuzeyi) civarında halen kömür ocağı olarak işletilmekte olan bölgede, Erken Miyosen yaşlı ostrakodlu, gastropodlu, marn, killi kireçtaşı ve kömür bantları ardalanması ve kiltaşı çökelleri içerir. Formasyon geri kalan alanlarda karmaşık görünümlü, rekristalize planktonik foraminiferli kiltaşlarmdan oluşmaktadır. Kahramanmaraş Havzası içinde, Alacık formasyonu, yaşlı birimleri, taban konglomerasıyla başlayan uyumsuzlukla veya normal faylı dokanakla üzerlemektedir. Bu birim inceleme alanında, yaşlı birimlerce bindirme faylanyla üzerlenirken; Akitaniyen-Burdigaliyen yaşlı resifal kireçtaşları, Erken-Orta Miyosen yaşlı kiltaşı ve kanal çökelleriyle uyumsuz olarak örtülmektedir. Bu da Alacık formasyonunun Geç Orta Eosen-Erken Miyosen dönemi arasında çökelime sahip olduğunu ve Akitaniyen başlarında yoğun bir tektonizmanın etkisinde kaldığını göstermektedir.The Alacık formation deposited during the transitional period between the compressional regime of the pre-Tertiary and strike slip fault tectonics developed after the Miocene. This formation shows different lithological properties in northern part of the Kahramanmaraş Basin. This unit, in vicinity of the Çukurhisar village (northwest of the Kahramanmaraş), starts with sandstone and conglomerates at the base, continues with claystone, and ends with latest Middle Eocene-Late Eocene large benthic foraminifera, extraclast bearing carbonate build-ups in the laminated claystone. The Alacık formation contains ostracoda-gastropoda bearing marl, clayey limestone - coal band alternations and claystone in the region which is still exploited as a coal mine near the Tekir Town (north of Kahramanmaraş). In the rest of the area, this formation includes chaotic appeared, recrystallized planktonik foraminifera bearing claystone. In the Kahramanmaraş Basin, the Alacık formation overlies the older units with unconformable contact starting with base conglomerate or normal faulted contact. This unit is overlain by older units with thrust faults, unconformably covered by Aquatanian-Burdigalian reef limestone and Early-Middle Miocene claystone and channel deposits in the study area. This indicates that the Alacık formation has a deposition in between the Latest Middle Eocene-Early Miocene was under the effect of intense tectonism at the beginning of the Aquatanian

Environmental interpretation of the Kuzgun formation in the Adana Basin through microfossils [Adana Havzasi Kuzgun formasyonunun mikrofosiller ile ortamsal yorumu]

The Adana Basin is bordered by the Ecemiş Fault Zone to the west, Taurus Mountain to the north, Amanos Mountain to the east and Mediterranean to the south. The Tertiary sequence of the Adana Basin is limited by Paleozoic and Mesozoic rock units at the base and Quaternary sediments at the top. This study deals with the Kuzgun formation in the Tertiary sequence. The Salbaş tuffite member of the Late Miocene Kuzgun formation, the subject of this study, lies along an east-west direction and has a thickness varying between 50 cm and 10 m. The benthic foraminiferal and ostracod assemblages are investigated for the purpose of determining the effects of the living conditions when the Tortonian of tuffite levels developed in the basin. For this reason, seven stratigraphic sections were measured from the region including tuffite levels. A total of 45 foraminiferal species from 31 genera, and 37 ostracod species from 26 genera were identified from 96 samples. Although these described benthic foraminiferal and ostracod species decrease or are even extinct in the tuffite levels, they show high diversities and similarities at the units situated above or below the tuffite levels. In addition, according to the benthic foraminiferal and ostracod assemblages, it is pointed out that the tuffite levels have been deposited in the lagoonal conditions in the eastern and shallow marinal enviroment of the western part of the basin

Environmental interpretation of the Kuzgun formation in the Adana Basin through microfossils

Adana Havzası; batıda Ecemiş Fay Kuşağı, kuzeyde Toros ve doğuda Amanos Dağları ve güneyde Akdeniz ile sınırlanmıştır. Adana Havzası Tersiyer istifi, tabanda Mesozoyik ve Paleozoyik yaşlı birimler ile üstte Kuvaterner yaşlı birimler arasında yeralmaktadır. Bu çalışma, Tersiyer istifini oluşturan birimlerden Kuzgun formasyonunda yapılmıştır. Geç Miyosen yaşlı Kuzgun formasyonu, Salbaş tüfit üyesi, batı-doğu uzanımlı, kalınlığı 50 cm ile 10 m arasında değişen şeritsel ve merceksel birim olarak yeralmaktadır. Havzada gelişen bu tüfit seviyelerinin Tortoniyen'de yaşam koşullarını nasıl etkilediğini belirlemek amacıyla içerdiği bentik foraminiferler ile ostrakodlar incelenmiştir. Bu amaçla, havzada tüfit seviyelerini içine alacak şekilde batıdan doğuya doğru yedi adet stratigrafi kesiti ölçülmüştür. Derlenen 96 örnekte, bentik foraminiferlerden 31 cins ve 45 tür ile ostrakodlardan 26 cins ve 37 tür tayin edilmiştir. Tanımlanan bentik foraminifer ve ostrakod türleri tüfitli seviyelerde azalıp veya yok olurken, tüfitlerin altındaki ve üstündeki birimlerde tür ve birey sayısı bakımından çeşitlenmeler ve benzerlikler görülmektedir. Ayrıca bentik foraminifer ve ostrakod topluluklarına göre; tüfit seviyelerinin havzanın batı kısmında sığ denizel, doğusunda ise lagün koşullarında depolandığı belirlenmiştir.The Adana Basin is bordered by the Ecemiş Fault Zone to the west, Taurus Mountain to the north, Amanos Mountain to the east and Mediterranean to the south. The Tertiary sequence of the Adana Basin is limited by Paleozoic and Mesozoic rock units at the base and Quaternary sediments at the top. This study deals with the Kuzgun formation in the Tertiary sequence. The Salbaş tuffite member of the Late Miocene Kuzgun formation, the subject of this study, lies along an east-west direction and has a thickness varying between 50 cm and 10 m. The benthic foraminiferal and ostracod assemblages are investigated for the purpose of determining the effects of the living conditions when the Tortonian of tuffite levels developed in the basin. For this reason, seven stratigraphic sections were measured from the region including tuffite levels. A total of 45 foraminiferal species from 31 genera, and 37 ostracod species from 26 genera were identified from 96 samples. Although these described benthic foraminiferal and ostracod species decrease or are even extinct in the tuffite levels, they show high diversities and similarities at the units situated above or below the tuffite levels. In addition, according to the benthic foraminiferal and ostracod assemblages, it is pointed out that the tuffite levels have been deposited in the lagoonal conditions in the eastern and shallow marinal enviroment of the western part of the basin

Coastal geology of Iztuzu Spit (Dalyan, Muğla, SW Turkey)

This study was carried out in İztuzu Spit (IS, Muğla-SW Turkey), which is a special environmental protection zone due to the presence of a loggerhead turtle breeding area. The aims of this study are: (1) to determine surface sediment content, (2) to investigate the İztuzu Spit spatial changes using Google-earth images, and (3) to figure out the controlling factors in the spit development. The main shore of the İztuzu Spit is predominantly composed of medium-grained sands that contain dominantly ophiolitic rock fragments. Five types of ostracods, sixteen types of benthic foraminifera, gastropods, mollusc, and bivalve shell fragments were identified from the sediment sample taken from coastal part of the IS. The main coastal area of the İztuzu Spit attached to mainland initially decreased from 67.4 ha (2004) to 56.8 ha (2013) then increased to 58.5 ha in 2016. Significant erosion of the main beach of İztuzu Spit was observed in the north-western edge. A small coastal region separated from the İztuzu Spit by the Dalyan river mouth shows significant change. The northern side of this region acted as a new sedimentation area, while the southern side was affected by erosion. The reason of these changes is variation in the flow direction of the Dalyan River mouth due to the building of piers in the lagoon side of the İztuzu Spit. The main coastal part of the İztuzu Spit has recently been under the effect of waves, tides, and summer tourism clients, while the river flow direction and anthropogenic effects are the main controlling mechanisms in the development of the NW edge. Therefore, the İztuzu Spit must be monitored continuously and protected as this region is the breeding zone of the loggerhead turtle

A paleoenvironmental test of the Messinian Salinity Crisis using Miocene-Pliocene clays in the Adana Basin, Southern Turkey

The Messinian Salinity Crisis is an important paleooceanographic event around the Mediterranean area. Due to the collision of the North African Plate with the European Plate the Mediterranean area lost its connection to the Atlantic. The Mediterranean sea became shallower; the biota changed and thick evaporitic beds were formed. Paleoenvironmental characteristics of Upper Miocene-Pliocene units of the Adana Basin have been explained by using clay mineralogy analysis. For this purpose, X-ray diffraction studies were carried out on 85 samples collected. In the Upper Miocene-Pliocene sequence high kaolinite content of siltstone, claystone, sandstone, marl and silty marl of the Tortonian units indicates a humid climate. During the Messinian, the content of kaolinite decreased, indicating that the area was arid. After the Messinian, the kaolinite content increased again, showing that environmental conditions of the area became humid again. Correlations of illite and smectite content indicate humidity and temperature of the paleoenvironment, according to previous studies carried out in sequences related to the Messinian Salinity Crisis. The illite content increased in the Tortonian, diminished during the Messinian and increased again in the Pliocene while the smectite ratio showed the opposite trend. In this study, illite ratio is increased during Tortonian and Messinian and decreased in Pliocene while smectite ratio is increased from Tortonian to Pliocene. © 2007 Elsevier B.V. All rights reserved.The authors are grateful for the financial support provided by TUBITAK (The Scientific and Technical Research Council of Turkey) and the Research Fund of Çukurova University. We also thank to the Turkish Petroleum Corporation for support of drill log samples in the study area