Yazar "Ulugergerli, Emin Ugur" seçeneğine göre listele

Listeleniyor 1 - 4 / 4
  • [ X ]
    Öğe
    An Overview of Modeling in Earth Sciences; Inferences from Environmental Geophysics Applications
    (Tmmob Jeoloji Muhendisleri Odasi, 2024) Uluocak, Ebru Sengul; Ulugergerli, Emin Ugur
    In an earth science-related research study, while investigating geological or engineering problems, numerical modeling functions in two stages; i) prior to the fieldwork, obtaining the survey parameters (conceptual model), and ii) subsequent to the fieldwork, confirming the accuracy of the estimated subsurface structures with the help of the conceptual model. Although the numerical modeling process alone is not sufficient in both stages, it is possible to converge the numerical models into a realistic subsurface structure with additional information obtained from interdisciplinary studies. In this article, a workflow is proposed employing modeling studies used in earth sciences. Environmental pollution studies carried out on a now-unused open waste disposal site in Canakkale (Turkiye) are presented following this workflow. Accordingly, tomography measurements were made by using the electrical resistivity method along the profiles determined based on a conceptual model, and then a hypothetical two-dimensional (2D) combined solute transport model was produced by obtaining the porosity cross-section from the subsurface resistivity structure of the study area. The results show the spatial and temporal variation of pollution in the landfill during the years that geophysical measurements (i.e., 2004, 2008, and 2009) were taken, and the numerical modeling time (13,6 yrs). Besides, the numerical modeling results provide a conceptual model for future pollution studies in this area, with the length and depth of the possible survey profile (similar to 40-250 m and 0-25 m, respectively). The results emphasize the importance of evaluating geophysical studies together with numerical models sensitive to the spatial and temporal spread of the pollution cloud emitted from a polluting source, such as an open dumpsite.
  • [ X ]
    Öğe
    Can an Earthquake be Predicted Using Meteorological Data?
    (Afet ve Acil Durum Yonetimi Baskanligi (AFAD), 2024) Uslan, Erdinc; Ulugergerli, Emin Ugur
    To investigate whether there is a relationship between earthquakes and meteorological data, earthquakes with magnitudes 4.0?Mw?7.0 were compared with daily average temperature, average wind speed, total rainfall and sea water temperature values in the Aegean Sea. On the contrary the news about changes in air temperature and sea water being precursors of earthquakes is frequently seen on both social media and in the national press, our study conducted with data covering the pre- and post-earthquakes has shown that such associations can only be explained by coincidences. It was observed that there is no relationship between 4.0?Mw?7.0 earthquakes and meteorological data in the Aegean Sea. © 2024 Afet ve Acil Durum Yonetimi Baskanligi (AFAD). All rights reserved.
  • [ X ]
    Öğe
    Marine effects on vertical electrical soundings along shorelines
    (Tubitak Scientific & Technological Research Council Turkey, 2017) Ulugergerli, Emin Ugur
    Onshore applications of direct current resistivity (DCR) along shorelines suffer a short-circuit-like phenomenon due to electrical current flowing through a more conductive body of water rather than ground. Our study of the numerical simulation of DCR data with a three-dimensional forward model demonstrated that the apparent resistivity was reduced as a function of the sea depth and the distance of measurement site to the shoreline. Furthermore, it was concluded that the marine effects on DCR data (i.e. reduction in apparent resistivity) become nonnegligible as the ratio of half-electrode expansion (AB/ 2) to the distance to the shoreline is larger than one. The reduction in apparent resistivity reaches its highest levels as the ratio approaches ten. Our survey conducted along the coastal line of Northwest Turkey clearly showed that if the marine effects are left untreated, one-or two-dimensional inversion yields incorrect resistivities for underlying units and therefore undermines the credibility of survey results. In the paper suggestions are made to handle such situations.
  • [ X ]
    Öğe
    Using non-derivative filters for the tectonic implcations: A case study in simav graben in western turkey
    (J and N Group, Ltd., 2019) Toker, Ceyhan Ertan; Cakir, Recep; Ulugergerli, Emin Ugur
    Gravity data compiled for Simav Graben and its surrounding area in western Turkey were reprocessed and reinterpreted by using a type of standard deviation filter and Euler deconvolution methods. Results from the interpretation of gravity data and seismological studies show presences of new intrusive structures in the vicinity of Simav Graben. A prominent intrusion is located in the NE margin of the graben and has a thickness of 12-15 km at 2.5-3 km below the surface. Numerous earthquakes recorded in the eastern part of the graben are associated with this intrusions. Our multi-disciplinary study using gravity and seismological data clearly delineate the Simav Graben, characteristics of the Simav Fault, and identified intrusion was named as Naşa. Seismicity within the same tectonic frame are also well correlated with the intrusive structures identified on the filtered gravity anomalies. © (2019) by Environmental and Engineering Geophysical Society All rights reserved.