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    Evaluation of asbestos exposure in dumanli village (çanakkale-Turkey) from a medical geology viewpoint: An inter-disciplinary study
    (General Directorate of Mineral Research and Exploration (MTA), 2015) Yi?itbaşi, Erdinç; Mirici, Arzu; Gönlügür, U?ur; Bakar, Coşkun; Tunç, Ismail Onur; Şengün, Firat; Işiko?lu, Özgür
    Biga Peninsula has many varied and interesting medical geologic problems, as well as being rich in natural geological resources. Mainly these problems are natural radioactivity, mineral dust, metal/mineral contamination in drinking water, acid rock/mine drainage, and problems related to geothermal and drinking water. With this view exposure to asbestos was surveyed and the results of this survey were evaluated by earth scientists and medical doctors. This inter-disciplinary study was done in Dumanli village (Çanakkale-Turkey) in the Biga Peninsula, NW Turkey. Studies have been carried out in earth sciences and the health sciences simultaneously. The asbestiform minerals around Dumanli village are contained in sheared serpentinites which occur as tectonic slices and lenses within Çamlica metamorphics. These tectonic slices and lenses are bounded by strike-slip faults and probably obtained their final tectonic positions in a transpressional regime during late Cretaceous-early Eocene time. Asbestiform minerals occur within stretching-shear zones in the strike-slip system. Petrographic and miner alo gic indications show that the asbestiform minerals are clinochrysotile, lizardite, antigorite and actinolite. In parallel with earth science studies; verbal autopsy, pulmonary function tests and radiological examination studies were carried out. A significant correlation between asbestos exposure and radiographic pathology was identified in the region and it was understood that the duration of exposure in these cases varies from 23-80 years.
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    Petrography and geochemistry of paragneisses in the Çine submassif of the Menderes Massif, Western Anatolia
    (2006) Şengün, Firat; Candan, Osman; Dora, O. Özcan; Koralay, Ersin
    The Menderes Massif, which covers a large area in western Turkey, is made up of Pan-African basement rocks and a Palaeozoic to Early Tertiary cover sequence. The study area is located in the Dalama and Hallaçlar (Aydin) area, in the northern and central parts of the Çine submassif of the Menderes Massif. The oldest units of the Pan-African basement are metaclastics, consisting of paragneisses and mica schists that gradually and conformably overlay paragneisses. Macroscopic appearances and mineralogical and textural data indicate that paragneisses can be subdivided into four subgroups. These are: (1) black spotted, (2) white spotted, (3) massive, grey-coloured and (4) massive, purple-coloured paragneisses. Geochemical data show that the spotted and purple-coloured paragneisses are characterized by high alumina content that is consistent with high sillimanite content. Paragneisses exposed in the eastern part of the Çine submassif were partly migmatized during the last stage of the polyphase Pan-African metamorphism. Based on comparison with relics of upper amphibolite to granulite (?) facies parageneses in the Pan-African basement of the Menderes Massif, we infer that the porphyroblasts in the black-spotted paragneisses are pseudomorphs after cordierite. Considering the inferred replacement of cordierite by sillimanite + garnet + biotite, it can be concluded that former high-temperature assemblages were overprinted by almandine-amphibolite facies metamorphism. Geochemical data obtained from paragneisses and mica schists reveal that the protoliths of this metaclastic sequence were derived from a cratonic provenance. The paragneisses are intruded by 550 Ma syn- to post-orogenic orthogneisses. Based on the well-preserved the original intrusive contact relationship with the orthogneisses and the youngest detrital zircon ages in paragneisses, it can be inferred that the time of deposition of their protolith is Late Proterozoic. Copyright © TÜBİTAK.