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Developing A Geotechnical Microzonation Model For Yenisehir (bursa) Settlement AreaKolat, Cagil 01 June 2010 (has links) (PDF)
The purpose of this study is to develop a geotechnical microzonation model
regarding the suitability of the residential areas in Yenisehir (Bursa, Turkey),
which is a currently developing settlement area in a seismically active region. For
this purpose, soil properties and dynamic soil behaviors of the study area were
assessed. Soil classification, soil amplification, natural soil predominant period,
resonance phenomena and liquefaction potential of the study area were
evaluated using borehole data and microtremor measurements. The raw data
obtained from the previous studies carried out at Yenisehir were used for these
assessments. The liquefaction potential for the study area was evaluated both in
two-dimensional planimetric and three-dimensional volumetric assessments. Two
geotechnical microzonation maps were produced for the study area according to
the surface damage due to liquefaction (according to two different methods), soil
amplification and distance to streams maps / by using Geographical Information
Systems (GIS) based Multi-Criteria Decision Analysis. The weight values were
assigned to the layers using Analytical Hierarchical Process method by pairwise
comparisons. Evaluating geotechnical microzonation maps produced, the safest
areas were found on the northern sites of the study area. The most critical areas
were found to be in the middle and the southeast parts of the study area.
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Effects Of Precipitation Recharge And Artificial Discharge On Salt Water-fresh Water Interface Movement In Selcuk Sub-basin: Climatic IndicationsAykanat, Gokben 01 February 2011 (has links) (PDF)
Fluctuations in temperature and precipitation amounts due to climate change influence recharge rate of groundwater. Any variations in the amount of precipitation recharge and artificial discharge directly affect groundwater level and so the salt water intrusion rate in the aquifers, which are in contact with sea water. The purpose of this study is to determine the overall historical precipitation recharge trend in Selç / uk sub-basin and to detect whether there is a decrease or increase in recharge amounts due to climate change since 1100 BC. Besides, it covers assessing the future position of the salt water-fresh groundwater interface as a result of possible fluctuations in climate and artificial discharge. For this purpose, numerical density dependent cross sectional groundwater flow with solute transport model was conducted using finite element approach. At first, current salt water-fresh water interface and artificial discharge related head changes in the aquifer were determined. Backward modeling was utilized to obtain concentration distribution in the year 1976 representing the last stage of the undisturbed period. Then, progradation of salt water-fresh water interface since 1100 BC to 1976 was modeled using calibrated parameters and current recharge value. As a result of sea-regression model simulations (1100 BC-1976) less degree of salt water intrusion than that of currently detected in the area was obtained. The result suggests that overall recharge amount in the last 3076 years must have been less than that of 1976. Moreover, future (2010-2099) position of the interface and head changes under the influence of both climate change and increasing water demand were determined. Future model simulations indicate that salt water-fresh water interface moves farther landward. However this movement is mostly due to increasing discharge amount rather than that of climatic changes.
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Gis Based Geothermal Potential Assessment For Western AnatoliaTufekci, Nesrin 01 September 2006 (has links) (PDF)
This thesis aims to predict the probable undiscovered geothermal systems through investigation of spatial relation between geothermal occurrences and its surrounding geological phenomenon in Western Anatolia. In this context, four different public data, which are epicenter map, lineament map, Bouger gravity anomaly and magnetic anomaly maps, are utilized. In order to extract the necessary information for each map layer the raw public data is converted to a synthetic data which are directly used in the analysis. Synthetic data employed during the investigation process include Gutenberg-Richter b-value map, distance to lineaments map and distance to major grabens present in the area. Thus, these three layers including directly used magnetic anomaly maps are combined by means of Boolean logic model and Weights of Evidence method (WofE), which are multicriteria decision methods, in a Geographical Information System (GIS) environment. Boolean logic model is based on the simple logic of Boolean operators, while the WofE model depends on the Bayesian probability. Both of the methods use binary maps for their analysis. Thus, the binary map classification is the key point of the analysis. In this study three different binary map classification techniques are applied and thus three output maps were obtained for each of the method. The all resultant maps are evaluated within and among the methods by means of success indices. The findings reveal that the WofE method is better predictor than the Boolean logic model and that the third binarization approach, which is named as optimization procedure in this study, is the best estimator of binary classes due to obtained success indices. Finally, three output maps of each method are combined and the favorable areas in terms of geothermal potential are produced. According to the final maps the potential sites appear to be Aydin, Denizli and Manisa, of which first two have been greatly explored and exploited since today and thus not surprisingly found as potential in the output maps, while Manisa when compared to first two is nearly virgin.
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Diagenesis Of Cudi Group Formations From Dincer-1 And South Dincer-1 Wells, Se Anatolia TurkeyOzkan Kahraman, Aysegul 01 January 2011 (has links) (PDF)
Dinç / er-1 (1968) and South Dinç / er-1 (1980) exploration wells are
located at Sirnak Province of Southeast (SE) Anatolia. South Fields of SE Anatolia have received a significant attention after the completion of subjected wells and numerous studies have been implemented regarding this area. Many theories about the
geological generation of these fields were put forward by people
who studied this region.Both wells have penetrated the Arabian Plate autochthonous units.
The Cudi Group, of this sequence, mainly consists of dolomites and anhydrites. The samples from the cores of this referred interval and the thin sections of these cores were examined in details by X-Ray Diffraction (XRD) Analyses and petrographic microscope. Thin sections taken from the core samples of the Cudi Group&rsquo / s Bakü / k, Ç / amurlu and Telhasan formations (from older to younger) stand out in the diagenetic manner. The analyses of these thin sections showed that dolomitization is the main diagenetic process along with some textural changes such as the increase in the deformation of algal structures, formation of stylolites and secondary porosity. Clay minerals, mainly illites, shows detritic behaviors rather than characters representing a diagenetic origin.
Obtained results from this study showed that the dolomitization as diagenetic process plays an important role in oil and gas formations within Cudi Group. Dolomite stoichiometry studies indicated that Cudi Group formations have modern dolomites since they show poor ordering reflections. They are also younger formations which are subjected to longer periods of diagenetic effects in comparison with Uludere Formation&rsquo / s dolomites.
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Genetic Modeling Of The Samli (balikesir) Iron DepositYilmazer, Erkan 01 March 2012 (has links) (PDF)
Samli Fe-oxide (+Cu± / Au) deposit is hosted by Samli pluton and rocks of Karakaya Complex in western Anatolia. The pluton consists of both mafic and felsic phases showing magma mixing textures. 40Ar/39Ar geochronology yielded an age range of 23.2± / 0.5 to 22.42± / 0.11 Ma for the Samli pluton, overlapping with 40Ar/39Ar age of 22.33± / 0.59 Ma and U-Pb age of 23.34± / 0.19 Ma from alterations. Sr-Nd isotope data are suggestive of a metasomatized subcontinental lithospheric mantle (SCLM) source for the magma.
Alteration-mineralization pattern is defined by a series of overlapping halos characterized by sodic-calcic (plagioclase-pyroxene± / scapolite), calcic (garnet-pyroxene± / epidote), potassic (biotite+magnetite+chalcopyrite), hematite-limonite, and late stage (chalcedony-calcite+native Cu) alterations. Stable (&delta / 18O, &delta / 34S) and radiogenic (87Sr/86Sr,143Nd/144Nd) isotope compositions suggest a magmatic source for the fluids responsible for alteration-mineralization. Given the spatial-temporal association of alteration-
mineralization with magmatic rocks, the hydrothermal system that controls mineralization in Samli appears to be linked with emplacement and cooling of Samli pluton.
Samli Fe-oxide (+Cu± / Au) deposit has features characteristic for both skarn- and Iron-Oxide-Copper-Gold (IOCG) type deposits. The spatial and temporal association with a porphyritic intrusion, widespread calc-silicate assemblage, metal content (abundant Fe-oxide with high copper content) are similar to calcic Fe-Cu skarns, whereas low-Ti (&le / 0.05% TiO2) magnetite/hematite, low-S sulfides (chalcopyrite> / pyrite), high Cu (up to 6.78%) and moderate Au (up to 8.82 ppm) grades, local structural control in alteration-mineralization, and the derivation of the causative magma from a SCLM resembles the features pertinent to IOCG type mineralization. Therefore, Samli deposit is defined as a skarn type Fe-Cu mineralization with a potential for IOCG type deposit.
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