Jeoloji Mühendisliği Dergisi
ABSTRACT: in 1999, two great earthquakes occurred around izmit and Adapazarı and caused tremendous damage to human lives and structures in the area. These earthquakes occurred along the North Anatolian Fault (NAF) which is one of the major structures of Anatolia, extending more than 1000 km. from east to west* There are many historical earthquakes of big magnitudes along this fault line.. There is an obvious phenomena in that the hipocentres of these earthquakes are migrating from east to west along the NAF and this implies that another big earthquake may hit Istanbul at the western end of the A[AF. Istanbul is one of the largest cities in the .Middle East representing, a. centre of economic, industrial, and touristic destination of modern Turkey. Therefore, if a big earthquake hits İstanbul, it will be a catastrophic national emergency In order to manage the potential earthquake disaster in Istanbul it is necessary to prepare a seismic disaster prevention/mitigation plan, emergency rescue plan and restoration /retrofitting plan of the earthquake stricken area from middle to long-term measures.
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ABSTRACT: Earthquake is the most important natural disaster in Turkey. The earthquake which struck Afyon on 03 February 2002 at 09:11:28am (local time) caused great losses in human life and property in Afyon and Us surroundings (Çay, Sultandağı, Bolvadin, Çobanlar). According to the earthquake regime triggered by the tectonics of the region, 252 earthquakes with a magnitude of 4.0 and greater have struck. Afyon and its surroundings `which are under the effect of the Gediz graben, Dinar, Akşehir, and Emirdağ fault systems exist within an active tectonic system leading to earthquakes with a magnitude of 4:0 and greater once in 5 months.fVith this characteristic, the` occurrence probabilities of earthquakes in 30 years with a magnitude of 6.0 and 7,0 are 78% and 35% respectively. The greatest earthquake recorded in this area was in 1931 with a magnitude of 7.0. In terms of the Earthquake Zoning Map of Turkey,. Afyon and its surroundings, where 8 earthquakes of a magnitude of 6.0 have occurred so far, are termed as first order earthquake province. In this study, firstly,: using macroseismic observations and distributions of aftershocks, the isoseist map of the earthquake region for 03 February 2002 event is made. Secondly, the location of ihe origin of 03 February 2002 (09:11:28am, Md=6.0, Mw=6..5) Earthquake is estimated. In this effect, it can be concluded that this event is a result of Akşehir Fault Zone and it is essential to name it as Çay (Afyon) Earthquake. Abundance of geothermal fluids sampled with respect to active faults in the region, sediments and alterated deposits containing abundant underground `water, and the construction of faulty and uncontrolled buildings are the main factors increasing the damage, hazard in earthquakes..
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ABSTRACT: The most important coal area of Turkey is situated in Zonguldak and province. The coal series occurred during Westfalien (Carboniferous) are lower-bounded by Visean aged karstic limestones and upper-bounded by Aptian-Barremian aged karstic limestones.. The isotope hydrology, which consists one of the studies dealed with karst hydrogeology, was held to determine the groundwater relations between the karstic limestones adjacent to the coal layers located in the Zonguldak coal mine areas. Environmental isotope samples were collected in the basin during 1994 - 1995 period, from the surface and groundwaters. Deuterium (2H), Oxigene -18 .(i8O) and Tritium (3H) analysis were carried out on the samples,. Recharge elevation, water origin and transit time of the groundwater system were determined with the evaluation of the analysis results. Waters encountered in the area are of marine origined rainfall, recharging at an elevation of 400-500 meters and consisting of shallow and deep circulation systems. Groundwater intruding the coal mine galleries, have a short flow period and are recharged from recent precipitations.
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ABSTRACT: Within the framework of this study, alteration feautures of the ore deposit, host rock alteration of copper-moiybdenium mineralization located around Domaniç (KÜTAHYA) have been studied by examination of drilling cores that were recovered by MTA during 1992-1993.Two diffèrent rock types, namely plutonic and subvolcanic, are distinguished within the study area, Plutonic rocks show as granular and porphyritic textures. The plutonic rocks which have granular texture are tonalite, granodiorite, quartz-diorite and granite, The other plutonic rocks with porphyritic texture are tonalite porphyry, quartz-diorite porphyry, granodiorite porphyry diorite porphyry and granite porphyry, Subvolcanic rock is aplite. The rocks except aplite in the study area are altered and mineralized Four different alteration types are distinguished in the rocks associated with mineralization. On the basis of alteration minerals.. These are (1) biotite-quartz, (2) sericite-quartz, (3) quartz-clqy-chlorite and (4) chlorite-epidote-quartz alteration types which exhibit an alternating pattern in the cores, Furthermore, a secondary alteration that is exhibited in the first meters of the drillings is amortization, Hetnatitization and argillization that has been formed by surface waters are also observed.
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ABSTRACT: The gold-bearing fluorite mineralizations are observed along the contacts between Devonian/?)- Carboniferous crystallized limestone of Malatya metamorphics and Permian schists, which unconformabfy overlie the former. The thickness of mineralization varies from 1 m to 30 m and the ore bearing zone may attain up to 10 km lengths along the unconformity surfaces. The lithological composition of the ore hearing zone is represented by conglomerate/breccia. The matrix: of breccia is mainly composed of quartz, fluorite and limoniie, The rock and ore fragments within the breccia are crystallized limestone, schist, chert and fluorite. Due to its high silica content, ore bearing zone present a different kind of morphology compared to surrounding rocks. Two different morphological features are present (1) unconformity-concordant, flat-lying and more or less tabular bodies (2) conical bodies extending downwards in the form ofkarstic cavity-fillings and they become narrower as they extend downwards.. The gold content of ore-bearing zone is highly variable.. The gold contents of the breccia ore containing graphitic organic material, reach up to 12,5 ppm. However, when there is no breccia texture and fluorite, the gold content gets much lower and decreases down to 100 ppb. In terms of geological position, structural-textural features, and mineral content, the Malatya-Yeşüyurt gold-bearing fluorite mineralization is a paleokarst type deposit formed on the imcorformity surfaces and believed to have been formed by karstification process thaï has continued in the region since Laie Eocene. Units consisting clay, sand and carbonate, which is overlying orebearing zone are favored as the most likely source of gold-bearing fluorite mineralization.. It is assumed that the components that formed the mineralization have been carried to the enriching environment by means of solutions that move deep down under gravity control Meanwhile, goldbearing fluorite mineralization is the first ever known mineralization its formation is based on karstification process at the Eastern Taurus Belt and whose distrubition is controlled by the uncorformity surfaces. Hence when its geological position and extension are concerned, this type of mineralization seems to be extremely important to form a basis for Jurther exploration studies in the Eastern Taurus Orojenic Belt.