Depositional features and coal potential of the Gölbaşı- Bahçeköy Neogene Basin, Ankara (Central Turkey)

The Bahçeköy coal field, which is the subject of this study, is located in the Gölbaşı Neogene basin in the south of Ankara (central Turkey). The pre-Neogene basement rocks located in the west and south of the basin are mostly composed of Permo-Triassic carbonate rocks, Cretaceous ophiolites, and Eocene turbidites. The coals in the Bahçeköy area are observed in the lower part of the Pliocene lacustrine sedimentary sequence which fills the basin. In the western part of the basin, the basalts and the lacustrine sediments, which contain coal, show intrusive contact relations in the lateral direction, during the Pliocene period, with the effect of the volcanism developing at the same time with sedimentation. Diatomite intercalations were formed at the upper parts of the lacustrine sequence which reached 12 m. The widespread observation of diatomites is quite important and it implies that the silicon-rich solutions associated with volcanism are involved in the lacustrine environment. The thickness of the economic coal level in Bahçeköy area varies between 4 and 12 m. According to these thicknesses, the total coal reserves calculated for the Bahçeköy area reach up to 16 million tons. The obtained drilling data shows that Bahçeköy coals exhibit rapid thickness and quality changes in the lateral direction. The chemical analyses point out these coals have average calorific value ranging from 7762 to 12,413 kJ/kg and ash content ranging from 44 to 65%. © 2019, Saudi Society for Geosciences

The importance of the ophiolithic rocks in the formation of heavy mineral placers: A case study from Burdur-Çamköy, SW-Turkey

Turkey, situated in the Alpine-Himalayan orogenic belt, is a country where ophiolithic rock assemblages cover a very large area. The ophiolithic nappes covering large areas in North Anatolia and the Taurus Mountains have emplaced on their present positions in the Late Cretaceous-Late Eocene period as a result of the obduction of oceanic crust slices of the Tethyan Ocean onto the continental crust. The Burdur-Yeşilova ophiolites commonly observed in SW-Anatolia consist mainly of dunite, peridodite, gabbro and diabase components, accompanied with layered chert and radiolarites. There are numerous massive and disseminated chromite ore deposits within the dunitic compounded peridodites. The sediments that may form the placer feature in Çamköy area have been formed by detrital sediments derived from the ophiolites in the Yeşilova region and transporting to southward by the rivers, resulting in deposits on the margin of the Acıpayam Graben. They contain heavy minerals such as chromite, vanadium magnetite and ilmenite dominantly. The aim of this study is to investigate in detail the heavy mineral content of Çamköy sediments, which has an important economical significance, to reveal the preliminary results of chromite and heavy mineral placers potential. For this aim, chemical and mineralogical (XRD) analyzes of the concentrate placer ore were carried out in addition to field observations. According to the studies carried out, it was determined that the placers in the region were predominantly composed of heavy mineral constituents consisting of chromite, vanadium, magnetite and ilmenite. According to the chemical analysis results, concentrated ore obtained from placers using shaking table, 22-27 % Cr2O3; 3-3.5% TiO2 and 0.3% V2O5. In addition to a considerable placer chromite reserve of 12 million tons in the region, the presence of significant titanomagnetite and ilmenite potential is also revealed in this study. According to these results, it is thought that if new enrichment methods are developed, the ore having the constituent which can be considered as economical can be recovered from the placers derived from ophiolites in the Çamköy region. © 2018, Hacettepe Universitesi Yerbilmleri. All rights reserved

Geç bulgu veren konjenital diyafram hernisinde torakoskopik diyafram onarimi: Olgu sunumu

Congenital diaphragmatic hernia is an important cause of respiratory distress and high mortality in neonates and rarely presents in older ages. Clinical features and results of late onset diaphragmatic hernia is different from hernias that encountered in newborns and considered as a variant of classical diaphragmatic hernia. A nine year old girl was who admitted with intermittent gastrointestinal symptoms and diagnosed as late onset congenital diaphragmatic hernia is presented to discuss the clinical features and the use of minimal invasive treatment modalities in late onset diaphragmatic hernia

The suboccipital, telovelar, transsuperior fovea approach to dorsal pontine lesions

Dorsal pons lesions at the facial colliculus level can be accessed with a suboccipital telovelar (SOTV) approach using the superior fovea safe entry zone. Opening the telovelar junction allows visualization of the dorsal pons and lateral entry at the level of the fourth ventricle floor. Typically, a lateral entry into the floor of the fourth ventricle is better tolerated than a midline opening. This video demonstrates the use of the SOTV approach to remove a cavernous malformation at the level of the facial colliculus. This case is particularly interesting because of a large venous anomaly and several telangiectasias in the pons. Dissections in the video are reproduced with permission from the Rhoton Collection (http://rhoton.ineurodb.org). The video can be found here: https://youtu.be/LqzCfN2J3lY

The lateral supracerebellar infratentorial, translateral mesencephalic sulcus approach to the mesencephalopontine junction

The lateral supracerebellar infratentorial (SCIT) approach provides advantageous access to lesions located in the lateral mesencephalon and mesencephalopontine junction. For lesions that abut the pial surface, a direct approach is ideal and well tolerated. For deep-seated lesions, the lateral mesencephalic sulcus (LMS) can be used to access lesions with minimal morbidity to the patient. This video demonstrates the use of the SCIT approach via the LMS to remove a cavernous malformation at the level of the mesencephalopontine junction. The use of somatosensory and motor evoked potential monitoring and intraoperative neuronavigation is essential for optimizing patient outcomes. Meticulous, multilayered closure is critical for optimal results in the posterior fossa. For optimal patient outcomes, approach selection for deep-seated lesions should combine the two-point method with safe entry zones. At follow-up, the patient had persistent sensory changes but was otherwise neurologically intact. The video can be found here: https://youtu.be/bHFEZhG8dHw

The suboccipital, telovelar, transsuperior fovea approach to dorsal pontine lesions

Dorsal pons lesions at the facial colliculus level can be accessed with a suboccipital telovelar (SOTV) approach using the superior fovea safe entry zone. Opening the telovelar junction allows visualization of the dorsal pons and lateral entry at the level of the fourth ventricle floor. Typically, a lateral entry into the floor of the fourth ventricle is better tolerated than a midline opening. This video demonstrates the use of the SOTV approach to remove a cavernous malformation at the level of the facial colliculus. This case is particularly interesting because of a large venous anomaly and several telangiectasias in the pons. Dissections in the video are reproduced with permission from the Rhoton Collection (http://rhoton.ineurodb.org). The video can be found here: https://youtu.be/LqzCfN2J3lY

Distribution of Natural Radioactivity from 40K\text{}^{40}K Radioelement in Volcanics of Sandıklı-Şuhut (Afyon) Area

Many radioactive elements have existed when the Earth had appeared and the long living of them are still present. One of the most important of these radioactive elements is $\text{}^{40}K$. It makes about 0.012% of total content of K, widely represented in many different rocks. In this study the distribution of the natural $\text{}^{40}K$ radioelement in the volcanics of the south part of Afyon was investigated. Gamma-ray spectrometer was used for in-situ measurements of this radioelement concentration. Studied area has covered approximately 1800 km². In-situ measurements were performed at 1390 different locations in this field. Data for each measurement was gathered during 3 min. The map of the ^{40}K element distribution in the studied area was produced. The high values of $\text{}^{40}K$, according to this map, were obtained in the areas of the alteration zones, between Sandıklı and Şuhut in the studied area