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31.
32.
A new method is introduced to determine the top and bottom depth of a vertical line using gravity anomalies. For this, gravity at a distance x from the origin and horizontal derivative at that point are utilized. A numerical value is obtained dividing the gravity at point x by horizontal derivative. Then a new equation is obtained dividing the theoretical gravity equation by the derivative equation. In that equation, assigning various values to the depth and length of vertical line, several new numerical values are obtained. Among these values, a curve is obtained for the one that is closest to the first value from attending the depth and length values. The intersection point of these curves obtained by repeating this procedure several times for different points x yield the real depth and length values of the line. The method is tested on two synthetics and field examples. Successful results are obtained in both applications. 相似文献
33.
Yeşim İslamoğlu 《International Journal of Earth Sciences》2009,98(8):1981-1990
?znik Lake is a tectonically originated basin mainly controlled by the E–W trending middle strand of the North Anatolian Fault (NAF) system. Pleistocene sediments occurring in front of the faults are well exposed both in the northern and in the southern shorelines of the basin. In this study, two endemic brackish water bivalve species, Didacna subpyramidata Pravoslavkev 1939 and Didacna nov. sp. were found in the oldest terrace of the northern Pleistocene sequence. Having characterized morphology, these species serve as stratigraphic indicators in the regional Pleistocene stratigraphy of the Ponto-Caspian region, and thus are well correlated to the assemblages of the early Khazarian subhorizon (Middle Pleistocene). Hence, these data demonstrate that the early Khazarian brackish water sea covered the study area. Additionally, a model for the formation of the basin is proposed: the ?znik lake basin was a gulf of the former Marmara Sea in the early Khazarian, connecting the Marmara to the Black Sea and the Caspian Sea. The subsequent regional prograding uplifts, main dextral strike-slip fault and many normal faults of the NAF Zone cut off the marine connections to the basin, leading to its present location and topographic level. 相似文献
34.
A multi‐element ion‐pair extraction method was described for the preconcentration of Cd(II), Co(II), Cr(III), Cu(II), Fe(III), Mn(II), Ni(II), Pb(II), and Zn(II) ions in environmental samples prior to their determinations by flame atomic absorption spectrometry (FAAS). As an ion‐pair ligand 2‐(4‐methoxybenzoyl)‐N′‐benzylidene‐3‐(4‐methoxyphenyl)‐3‐oxo‐N‐phenyl‐propono hydrazide (MBMP) was used. Some analytical parameters such as pH of sample solution, amount of MBMP, shaking time, sample volume, and type of counter ion were investigated to establish optimum experimental conditions. No interferences due to major components and some metal ions of the samples were observed. The detection limits of the proposed method were found in the range of 0.33–0.9 µg L?1 for the analyte ions. Recoveries were found to be higher than 95% and the relative standard deviation (RSD) was less than 4%. The accuracy of the procedure was estimated by analyzing the two certified reference materials, LGC6019 river water and RTC‐CRM044 soil. The developed method was applied to several matrices such as water, hair, and food samples. 相似文献
35.
In this study, it was aimed to characterize temporal variations of air pollutants for determining contribution to pollution episodes and to obtain correlations between these pollutants. With this aim we used data analysis for measured sulfur dioxide (SO2), particulate matter (PM, black fume and PM10), nitrogen oxides (NOx), ozone (O3), carbon monoxide (CO), methane (CH4), and non‐methane hydrocarbons (NMHC) recorded in Kocaeli, one of the most industrilizated cities of Turkey. Pollutant concentrations were the results of continuous and semi‐automatic measurements. Semi‐automatic measurements of SO2 and PM (black fume) were enclosing period from 1987 to 2008 whereas continuous monitoring of all pollutants included years of 2007–2009. In the first stage of the study daily, monthly, annual, and seasonal variations of pollution were researched. Annual average concentrations were compared with limits set by Air Quality Protection Regulation (AQPR), Air Quality Evaluation and Management Regulation (AQEMR), World Health Organization (WHO), European Union (EU), and National Ambient Air Quality Standards (USEPA). In the following stage relationships between pollutants such as NO2–O3, NOx–CO, NOx–NMHC, and NOx–SO2 were investigated and correlation coefficients were determined as 0.87, 0.56, 0.51, and 0.69, respectively. R2 values of regression models developed from these correlations were 0.78, 0.56, 0.34, and 0.72, respectively. Vehicle density of the traffic was evaluated with NOx–O3 emissions and decrease was seen in NOx emissions due to decreasing vehicle density at weekends whereas O3 concentrations increased. These correlations enable prediction of the parameters that cannot be measured which is important for providing improvement in early warning systems. 相似文献
36.
M. Erdik K. ŞeşetyanM.B. Demircioğlu U. HancılarC. Zülfikar 《Soil Dynamics and Earthquake Engineering》2011
This article summarizes the work done over the last decades regarding the development of new approaches and setting up of new applications for earthquake rapid response systems that function to estimate earthquake losses in quasi-real time after an earthquake. After a critical discussion of relevant earthquake loss estimation methodologies, the essential features and characteristics of the available loss estimation software are summarized. Currently operating near-real-time loss estimation tools can be classified under two main categories depending on the size of area they cover: global and local systems. For the global or regional near-real-time loss estimation systems: GDACS, WAPMERR, PAGER, and NERIES-ELER methodologies are presented together with their loss estimations for the 2009 Abruzzo (L’Aquila) earthquake in Italy. Examples are provided for the local rapid earthquake loss estimation systems, including the Taiwan Earthquake Rapid Reporting System, Real-time Earthquake Assessment Disaster System in Yokohama, Real Time Earthquake Disaster Mitigation System of the Tokyo Gas Co., and Istanbul Earthquake Rapid Response System. 相似文献
37.
The paper presents an approach to investigate the effects of some parameters on seakeeping assessment of fast ships in conceptual design stage. Hull form parameters have been classified into two groups: main dimensions (L, B and T) and secondary form parameters (LCB and CP). To demonstrate the approach a fast ship is redesigned as parent hull and alternative hull forms are generated by changing these parameters systematically. Some hull forms are selected related the geometric limits and seakeeping analyzes are here investigated and discussed. The obtained results are satisfactory for seakeeping predictions during the conceptual design stage. 相似文献
38.
39.
The Çöpler epithermal Au deposit and related subeconomic porphyry Cu–Au deposit is hosted by the middle Eocene Çöpler–Kabata? magmatic complex in central eastern Anatolia. The intrusive rocks of the complex were emplaced into Late Paleozoic–Mesozoic metamorphosed sedimentary basement rocks near the northeastern margin of the Tauride-Anatolide Block. Igneous biotite from two samples of the magmatic complex yielded 40Ar/39Ar plateau ages of 43.75?±?0.26 Ma and 44.19?±?0.23, whereas igneous hornblende from a third sample yielded a plateau age of 44.13?±?0.38. These ages closely overlap with 40Ar/39Ar ages of hydrothermal sericite (44.44?±?0.28 Ma) and biotite (43.84?±?0.26 Ma), and Re–Os ages from two molybdenite samples (44.6?±?0.2 and 43.9?±?0.2 Ma) suggesting a short-lived (<1 my) magmatic and hydrothermal history at Çöpler. No suitable minerals were found that could be used to date the epithermal system, but it is inferred to be close in age to the precursor porphyry system. The Çöpler–Kabata? intrusive rocks show I-type calc-alkaline affinities. Their normalized trace element patterns show enrichments in large ion lithophile and light rare earth elements and relative depletions in middle and heavy rare earth elements, resembling magmas generated in convergent margins. However, given its distance from the coeval Eocene Maden–Helete volcanic arc, the complex is interpreted to be formed in a back-arc setting, in response to Paleocene slab roll-back and upper-plate extension. The tectonomagmatic environment of porphyry-epithermal mineralization at Çöpler is comparable to some other isolated back-arc porphyry systems such as Bajo de la Alumbrera (Argentina) or Bingham Canyon (USA). 相似文献
40.
Effects of basin activities and land use on water quality trends in Tahtali Basin, Turkey 总被引:1,自引:1,他引:0
Bi-weekly water quality data from seven monitoring stations located within Tahtali Watershed, ?zmir, Turkey and digital land use/land cover data of the same watershed are analyzed in this study. To examine the changes in land use associated with urbanization, the satellite images of the main pool of the Tahtali reservoir prior to filling and subsequent to filling, respectively, are analyzed. Aerial photos of the basin taken in 1995 (October) are compared with images taken in 2005 (November) from the IKONOS satellite through use of several GIS techniques. New residential buildings, greenhouses, and industrial buildings are presented in separate layers, and changes in basin activities are quantified. The effects of urbanization on the water quality are investigated through statistical analysis. The seasonal Kendall test is applied to the water quality parameters monitored bi-weekly at seven stations within the basin for the duration 1997–2005. There was no trend in phosphorus, but there was a negative trend in boron and nitrate and a positive trend in the parameters of biological oxygen demand (BOD) and chemical oxygen demand (COD). The improvement in nitrate concentrations is attributed to the new regulations on the use of fertilizers in greenhouses. However, increase of BOD and COD concentrations is related to the growing settlement areas and industrial zones, which point to the insufficient wastewater treatment within the basin. Soil erosion within the basin is also quantified by the universal soil loss equation using available maps. Estimated total soil loss rate increased about 2.5 times that of 1995 when the changed land use composition in 2005 is considered in the calculations. 相似文献