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Dünyada enerji kaynaklarının rastgele dağılmış olması, yükselen enerji fiyatları, küresel ısınma ve iklim değişikliği gibi çevresel sorunlar, yakın gelecekte fosil yakıtların tükenecek olması, bu enerji kaynaklarının çevre ve insan sağlığı üzerindeki etkileri, yabancı kaynaklara ve az sayıda enerji zengini ülkeye bağımlılık sebebiyle ülkeler farklı enerji kaynaklarına yönelmiştir. Uranyumu yakıt olarak kullanan nükleer enerji üretimi Türkiye için alternatif bir kaynak olarak ele alınmaktadır. Türkiye’nin kanıtlanmış uranyum rezervi 32.4 kiloton olup, halen uranyum içerebilecek havzaların araştırılması devam etmektedir. Bu kapsamda, Pliyo-Miyosen genişlemeli rejim sonucu gelişen Dinar (Afyonkarahisar, Batı Anadolu) kömür oluşumları ekonomik açıdan önem arz edebilecek uranyum içerikleri bakımından ilgi çekebilmektedir. Çeşitli derinliklerden ve 5 sondaj kuyusundan toplam 17 adet kömür numunesi alınmıştır. Bu numunelerin uranyum içeriklerinin 1065 μg/g mertebelerine kadar çıktığı görülmüştür. Havzada mevcut olan uranyumun, kömürleşme süreci ve kömür tabakalarının üzerinin volkanoklastik sedimanlar tarafından örtülmesinden sonra, hidrotermal akışkanlar ile karışan yeraltı sularının etkisiyle katmanlı epijenetik köken modeline uygun şekilde oluştuğu düşünülmektedir. Ayrıca, yüksek uranyum içeriğinin, linyit damarlarının üst katmanlarında yoğunlaşması sebebiyle havza diğer epijenetik linyit oluşumları ile benzerlik göstermektedir., Random distribution of energy resources in the world, rapidly increasing energy prices, environmental problems such as global warming and climate change, the depletion of fossil fuels in the near future and their negative impact on the environment and human health, increasing dependence on foreign energy, limited energy resources of big consumer countries and being dependent on a small number of specific countries lead states to seek various sources of energy. The uranium fuel-based nuclear energy generation is an alternative energy source for Turkey. Proven uranium reserves in Turkey are 32.4 kt and exploration of sedimentary basins for uranium mineralization still continues. In this context, Dinar (Afyonkarahisar, western Turkey) coal occurences can attract attention for economic possibilities of uranium related with Plio-Miocene aged extensional tectonic regime. A total of 17 coal samples were collected for analyses from five boreholes at various depths. The uranium contents of studied coals are up to 1065 μg/g. The origin of the uranium in this basin are considered as a stratal epigenetic origin, which the uranium was introduced in the coal after coalification and consolidation of the enclosing sediments by ground water deriving uranium from hydrothermal sources or from unconformably overlying volcanic rocks. In addition, it can be highlighted that the higher contents of uranium occur in the upper parts of the stratigraphically highest lignite beds, which is compatible with other epigenetic lignite deposits.

Determining and continuously monitoring the quality parameters (proximate and calorific value analysis) of coal is crucial for mining, power generation, and trading purposes. Although proximate and calorific analyses are compulsory for monitoring, on-line methods continuously determine these parameters using expensive, detached equipment. Few studies predict the coal quality parameters using image analysis of the optical changes of coal surfaces. This study aimed to test the hypothesis that the surface color of coal samples might be an indicator for coal quality parameters. A novel method is proposed to estimate the ash content, fixed carbon, and gross calorific value of the given coals by analyzing the colored images of coal samples. Thirty-five coal samples from seven lower-rank coalfields in Turkey were examined through proximate and calorific analyses. For this preliminary study, they were photographed to obtain digital images, processed to calculate each pixel's RGB codes as 8-bit values and normalized RGB codes, i.e., chromaticity values. The analyses showed that blue and red chromaticity values are highly correlated with ash content, fixed carbon content, and calorific values.

Dünya’da yeraltı kömür madenciliğinde, yıllardır büyük can ve mal kayıplarına neden olan ani gaz ve kömür püskürmesi olayları, yurdumuzda da Zonguldak Taşkömürü Havzası’nda meydana gelmekte olup, acil olarak çözümlenmesi gereken iş kazası nedenleri arasında yer almaktadır. Havzada 1969-2013 yılları arasında 90 adet ani gaz ve kömür püskürmesi olayı kaydedilmiş ve toplam 374 kişi hayatını kaybetmiştir. 2013 tarihinden günümüze kadar geçen sürede havzada herhangi bir olay gerçekleşmemiştir. Bu çalışmada, ani gaz ve kömür püskürmesi olayı tanıtılmış, olayın meydana gelişinde rol oynayan ana faktörler sıralanarak, oluşum mekanizması kısaca açıklanmıştır. Ayrıca havzada kayıtlara geçen olayların istatistiksel bir değerlendirmesi yapılmış, olaylarla mücadele uygulanan yöntemler özet olarak verilmiştir.

Coal and gas outbursts have been a major geological hazard to underground coal mining for over 150 years and continue to cause serious problems in all over the world. In order to have a better understanding of the phenomenon, it is worthwhile making a historical review of the occurrences and a combat of the events. Many investigations and researches have been done to characterize and prevent the outburst occurrences in the worldwide, but there has been no detailed investigation about coal and gas outburst occurrences in Turkey. This paper presents the outburst data of coal mines in Turkey since 1969. Based on the observation of outburst occurrence in Turkey in the period from 1969 to 2012 as well as mining and geological conditions, detailed analysis of the possible causes of outburst accidents is conducted. The influences of some geological parameters such as the depth of occurrence, thickness and inclination of coal seams, the amount of ejected material (coal and gas), and tectonic disturbances on coal and gas outburst occurrences have been statistically investigated. The outburst occurrences throughout the world were reviewed and compared with the Turkish outburst experiences. Suggestions are put forward on future studies that could be of interest to government agencies regarding strategic policies, proper technical management practice, identification of outburst-prone coal seams, as well as prevention and control measures.

Airblast disturbances, like ground vibrations, are undesirable by-products of blasting. Airblast damage and annoyance are directly related to factors such as blast design, weather and terrain conditions, and human response. But, unlike blast induced ground vibrations, airblast impacts the structures through the roof, walls and windows leading to human annoyance. Because any structure rumbling and rattling, including blast induced vibrations can fuel the fear of people. The experiences on airblast-overpressure (AOp) measurements show that it is sometime impracticable to set a maximum AOp limit, with or without allowed appropriate percentile of exceedances, because of the significance and unpredictability of variable geological conditions and the restrictive character of this kind of limitations in blasting practice. We therefore utilized the method of modified scaled distances (SDs) based on empirical equations considering such factors as blasting parameters and geological parameters of rock mass for bench blasting in quarries. The aim of this application was to get an environmentally friendly and technically practicable results by using site specific SDs instead of conservative SD values. This method was realized in a quarry in Istanbul with numerous experimental shots. In these experiments, the levels of airblast-overpressures were investigated as a function of variable conditions. The results show that the performances of these estimations are governed by the site-specific character of these empirical relations.

Radon measurements were carried out in Kozlu, Karadon and uzulmez underground coal mines of Zonguldak bituminous coal basin in Turkey. Passive-time integrating method, which is the most widely used technique for the measurement of radon concentration in air, was applied by using nuclear etched track detectors (CR-39) in the study area. The radon concentration measurements were performed on a total of 42 points in those three mines. The annual exposure, the annual effective dose and lifetime fatality risk, which are the important parameters for the health of workers, were estimated based on chronic occupational exposure to the radon gas, which is calculated using UNCEAR-2000 and ICRP-65 models. The radon concentrations at several coal production faces are higher than the action level of 1000 Bq m - 3 . It is suggested that the ventilation rates should be rearranged to reduce the radon concentration.