Permian-Triassic and Late Cretaceous accretionary complexes, ascribed to the consumption of two distinct oceans, the Paleo-and Neo-Tethys, are exposed over extensive areas in the Eastern Mediterranean region. However, a separating continental ribbon, the so-called Cimmeride continent, between the Paleo-and Neo-Tethys during early Mesozoic time cannot be defi ned. Here we report a previously unknown Early Jurassic metamorphic oceanic accretionary complex and ophiolite from northeast Turkey, bounded by oceanic accretionary complexes of Permian-Triassic and Late Cretaceous age to the north and the south, respectively, without a continental domain in between. This special tectonic position and widespread coexistence of Permian-Triassic and Late Cretaceous accretionary complexes alongside the Izmir-Ankara-Erzincan suture imply that (1) the southern margin of Laurasia in the eastern Mediterranean region grew by episodic accretionary processes from late Paleozoic to end-Mesozoic time without involvement of a Cimmerian continental ribbon, and (2) the Paleo-Tethys and northern branch of the Neo-Tethys were not distinct oceans in the Eastern Mediterranean region.

The obliteration of the Neo-Tethyan Ocean and collision of the microplates along the northern part of Turkey led to the development of the İzmir-Ankara-Erzincan suture zone (IAESZ). After the collision of Pontides with the Central-Anatolian Crystalline Complex (CACC) in the Paleocene, a new phase of extension and volcanism concomitantly developed along the northern (Almus; Pontides) and southern (Yıldızeli; CACC) sides and along the IAESZ during the Middle Eocene time interval. The first products of the Middle Eocene volcanism in these areas are represented by calc-alkaline to alkaline (basic-intermediate) volcanic and volcanoclastic units together with late-stage trachytic dikes, plugs, and stocks. The mantle source area of both volcanic units displays a metasomatized character, which was dominantly fluxed by sediment-sourced melts. The partial melting of the metasomatized source area gave rise to first-stage basic-intermediate volcanism in the crustal levels. Simultaneously with the generation of the first-stage volcanism, basaltic trachyandesitic shallow-seated magma mushes were also developed. The reactivation of these shallow-seated mushes by latestage extensional tectonics gave rise to the development of trachytic volcanism in both regions, which have a high-K to shoshonitic character. Almus trachytic lavas are phenocryst-poor and have differentiated Mg# numbers (avg. 26). On the other hand, Yıldızeli trachytic lavas have a broad compositional range (benmoreite to latite); they are phenocryst-rich and show more basic character (Mg# avg. 40). Trachytic volcanism in both areas is largely controlled by fractional crystallization of similar basaltic trachyandesitic parental magma with minor assimilation of the upper crustal lithologies. 40 Ar-39 Ar ages from sanidine phenocrysts from both areas also confirm that trachytic volcanism in both regions developed nearly coevally in different tectonic blocks (~41-40 Ma). Generation of similar volcanism on the different tectonic blocks during the postcollisional stage was probably governed by a regional-scale delamination and/ or lithospheric removal-related tectonomagmatic processes.

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Two isolated metamorphic accretionary complexes of Jurassic age, the Refahiye and Kurtlutepe metamorphic rocks, crop out as tectonic slices within the coeval suprasubduction-zone ophiolite at the southern margin of the Eastern Pontides (NE Turkey), close to the İzmir-Ankara-Erzincan suture. The Refahiye metamorphic rocks are made up of greenschist, marble, serpentinite, phyllite and minor garnet amphibolite, garnet micaschist and metachert. The whole unit was metamorphosed under garnet-amphibolite-facies conditions and strongly retrogressed during exhumation. The Kurtlutepe metamorphic rocks consist of subgreenschist-facies metavolcanics, metavolcaniclastics, marble, calc-phyllite, and minor serpentinite and metachert. Metabasites in the Refahiye metamorphic rocks are represented by four distinct geochemical affinities: (i) cumulate "flavor," (ii) alkaline oceanic island basalt (OIB), (iii) enriched mid-ocean ridge basalt (E-MORB) and (iv) tholeiitic island arc basalt (IAB). On the other hand, the Kurtlutepe metavolcanic rocks display only tholeiitic to calc-alkaline island arc geochemical affinities. The metabasic rocks with OIB affinities were interpreted as parts of the accreted oceanic islands, and those with E-MORB affinities as parts of accreted ridge segments close to oceanic islands and/or plume-distal mid-ocean ridges with a mantle previously metasomatized by plume components. The metabasic rocks with IAB affinities might have been derived from the overlying suprasubduction ophiolite and/or arc domain by a number of tectonic or sedimentary processes including tectonic slicing of accretionary complex and overlying fore-arc ophiolite, juxtaposition of the magmatic arc with subduction zone by strike slip faults, submarine gravity sliding and debris flows or subduction erosion. However, totally recrystallized nature of the metabasic rocks together with field relations does not allow any inference on the processes involved. The Kurtlutepe metavolcanic rocks might represent collided and accreted oceanic island arc with the subduction zone. Attempted subduction of an intraoceanic island arc may also explain the magmatic lull during Late Jurassic-Early Cretaceous in the Eastern Pontides.

Natural history collections and museums made their appearance in the Ottoman in late 19th century through various attempts to build collections through field excursions, donations and exchanges among researchers, individuals and institutions around the world. Among them, the Imperial Medical School of the Ottoman Empire, schools of the American Board of Commissioners for Foreign Missions (ABCFM) and other American educational groups and French colleges stand out with their vast collections from various parts of the Ottoman Empire and beyond. While these museums were created and built by eminent curators and researchers, a considerable amount of work was carried out by uncredited staff and the students. The history of these museums was often obscured by catastrophic events such as the great fires in Istanbul, the passing of the curators and other administrators and, particularly, the devastating effects of the First World War. However, long-lasting commercial science objects networks and the establishment of global natural history collections and museums are still operational today, supported by scientific exchange between other countries and the Ottoman Empire during the 19th and early 20th centuries. Drawing an outline of the history of the natural history collections of the Ottoman Empire can shed light on the evolution of both the naturalistic movement within the Ottoman society and an embryonic scientific network around the Middle East and the rest of the world.

On dokuzuncu yüzyıl boyunca Osmanlı İmparatorluğu, endüstriyel kalkınma planlarının kapsamında, dünyanın farklı yerlerinden mühendis, bilim insanı ve uzmanları davet etmiştir. Bu uzmanlar arasında, az bilinenlerden biri James Lawrence Smith'tir (1818Smith'tir ( -1883. Dönemin aydınlanmacı ruhuna uygun şekilde, çok yönlü bir bilim insanı olarak yetişmiş olan John Lawrence Smith, Osmanlı İmparatorluğunda pamuk ziraatini geliştirmek amacıyla 1846 yılında Sultan Abdülmecid tarafından davet edilen uzmanlardan biridir. Buna karşın, bu alandan farklı olarak; mineraloji, madencilik, termal kaynaklar ve jeokimya alanlarında öncü çalışmalar yapmış efesit, liebigit ve mecidit isimlerini verdiği farklı mineral türlerini keşfetmiştir. Bunun yanı sıra farklı maden ve mineral yatakları keşfeden Smith, Batı Anadolu ve İsrail civarındaki termal kaynakları incelemiş, bu kaynaklardan aldığı örneklerin kimyasal analizlerini yapmıştır. İstanbul'da geçirdiği süre boyunca günümüzde Fişekhane olarak bilinen demir-çelik fabrikasında mineraloji ve metalurji dersleri veren Smith, 1850 yılında Osmanlı İmparatorluğundan ayrılmıştır.

Abstract:The obliteration of the Neo-Tethyan Ocean along the northern part of Turkey leads the development of the İzmir-Ankara-Erzincan suture zone (IAESZ). After the suturing stage; extension and magmatism concomitantly developed on the both sides and along the IAESZ during the middle Eocene. During this stage, the areas confining to Almus, Yıldızeli, and Yıldızdağ regions have experienced a severe magmatic activity. Middle Eocene magmatism in Almus and Yıldızeli areas are represented by the volcano-sedimentary successions. Besides, in Yıldızdağ region, gabbroic and dioritic intrusives are the dominant manifestations of magmatism. The volcano-sedimentary successions from Almus and Yıldızeli areas represented by shallow marine sedimentary units at the lower parts and lava flows and volcanoclastic units at the middle to upper parts. Eight volcano-sedimentary sections from Almus and Yıldızeli measured to demonstrate the evolution of the magmatic units developed coevally along the both sides of the suture zone. In both regions; three different volcanic episodes are differentiated based on stratigraphy. First episode includes amphibole-basaltic andesite, andesite, and dacite. Second episode contains basalt and pyroxene-basaltic andesite lavas and third episode represented by trachyte and trachyandesite dikes and stocks. The field data from the all regions demonstrated that middle Eocene magmatic units along the post-collision zone concominantly developed in a wide area and triggering of the magmatism controlled by the region-scale delamination and/or lithospheric removal processes.