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Ömer Bozkaya, Hüseyin Yalçin and Hüseyin Kozlu

Clay mineralogy of the Paleozoic-Lower Mesozoic sedimentary sequence from the northern part of the Arabian Platform, Hazro (Diyarbakır, Southeast Anatolia)

The Paleozoic-Lower Mesozoic units in the Diyarbakır-Hazro region consist of sandstone (subarkose, quartz arenite), mudstone, shale, coal, marl, dolomitic marl, limestone (biomicrite, lithobiosparite, biosparite with lithoclast, dololithobiosparite, dolomitic cherty sparite) and dolomite (dolosparite, dolosparite with lithoclast, biodolosparite with glauconite). These units exhibit no slaty cleavage although they are oriented parallel to bedding planes. The sedimentary rocks contain mainly calcite, dolomite, quartz, feldspar, goethite and phyllosilicates (kaolinite, illite-smectite (I-S), illite and glauconite) associated with small amounts of gypsum, jarosite, hematite and gibbsite. The amounts of quartz and feldspar in the Silurian-Devonian units and of dolomite in the Permian-Triassic units increase. Kaolinite is more commonly observed in the Silurian-Devonian and Permian units, whereas illite and I-S are found mostly in the Middle Devonian and Triassic units. Vertical distributions of clay minerals depend on lithological differences rather than diagenetic/metamorphic grade. Authigenetic kaolinites as pseudo-hexagonal bouquets and glauconite and I-S as fine-grained flakes or filaments are more abundantly present in the levels of clastic and carbonate rocks. Illite quantities in R3 and R1 I-S vary between 80 and 95 %. 2M 1+1M d illites/I-S are characterized by moderate b cell values (9.005-9.040, mean 9.020 Å), whereas glauconites have higher values in the range of 9.054-9.072, mean 9.066 Å. KI values of illites (0.72-1.56, mean 1.03 Δ2θ°) show no an important vertical difference. Inorganic (mineral assemblages, KI, polytype) and organic maturation (vitrinite reflection) parameters in the Paleozoic-Triassic units agree with each others in majority that show high-grade diagenesis and catagenesis (light petroleum-wet gas hydrocarbon zone), respectively. The Paleozoic-Triassic sequence in this region was deposited in the environment of a passive continental margin and entirely resembles the Eastern Taurus Para-Autochthon Unit (Geyikdağı Unit) in respect of lithology and diagenetic grade.

Open access

Ebru Taştekin, Ufuk Usta, Ayşegül Kaynar, Çiğdem Özdemir, Ömer Yalçin, Filiz Özyilmaz and Ali Kemal Kutlu

Abstract

A congenital pulmonary airway malformation is a rare disorder of the pulmonary airway and a hamartomatous mass of disorganized lung tissues with various degrees of cystic change. A 20-year-old pregnant woman who did not have previous clinical follow-up during her pregnancy visited the gynecology department for her first check on the 19th week of gestation. The sonogram, showed severe hydrops fetalis. Laboratory findings were consistent with non-immune hydrops fetalis. Medical abortion was performed and the fetus was sent to our department for a complete fetal autopsy. Macroscopically, whole parts of the fetus had striking oedema. Massive pleural and peritoneal effusions were seen on dissection. The left lung filled the whole thoracic cavity. The heart was displaced to the right and the right lung was compressed. Microscopically, the left lung mass showed dilated bronchiole-like structures (1-20 mm) that were lined with ciliated columnar cells without any intervening mucinous cells. The subepithelial stroma contained thin, interrupted smooth muscle fibers and elastic connective tissue without cartilage plates. Our case is a very good example of non-immune hydrops fetalis associated with congenital pulmonary airway malformation type 2. Prenatal clinical and ultrasonographic follow-ups during pregnancy are very important for early diagnosis of congenital malformations.