Aquifer parameter estimation using an incremental area method

Theoretical well functions have been derived over the years to predict ground water level behaviour in aquifer systems under stress owing to groundwater extraction. The drawdown data collected during pump tests are typically analysed using graphical curve‐matching procedures to estimate aquifer parameters based on these well functions. Difficulty in aquifer characteristic identification and parameter estimation may arise when the field data do not perfectly match the drawdown curves obtained from the well functions. The present study provides a new method for the interpretation of aquifer pump tests which supplements the existing curve‐matching procedures in case ideal conditions do not exist; the proposed method provides a greater degree of flexibility in the data analysis for diagnostic tool purposes. The method, referred to as the Incremental Area Method (IAM) is based on integrating the logarithmic‐based drawdown curves within a discrete time and matching the results with a corresponding time integral of the Theis ( 1935 ) Well Function which governs ideal confined aquifers. The application of the proposed method to synthetically generated data and field data showed that IAM represents a viable method which yields information on potential non‐idealness of the aquifer and provides aquifer parameter estimates thus potentially overcoming drawdown data curve‐matching difficulties. Copyright © 2011 John Wiley & Sons, Ltd.     

Spatial Variation of the Precipitation Chemistry in the Thrace Region of Turkey

Pollutants affect not only the environment in which they originate since they are also transported by air currents to other locations. For this reason, air pollution is a global problem for all countries and the air and water quality need to be monitored carefully. More information on precipitation chemistry is required to determine the source of pollution as well as its effects on the ecosystems. In this study, precipitation chemistry has been analyzed for the first time by using simple bulk collectors located at four different sites in Northwest Turkey for a period of two years. About 650 sequential rainwater samples were collected and analyzed for pH, electrical conductivity, anions such as , , Cl^?, and cations such as Na⁺, K⁺, Mg²⁺, Ca²⁺, and . The selected sites were under the effect of different environmental factors. Our results showed that the highest and concentrations were measured in the Northwest of the research area. Additionally, it has been found that Ca²⁺ ions are abundant within all rainwater samples.     

Selective Separation and Preconcentration of Fe(III) and Zn(II) Ions by Solvent Extraction Using a New Triketone Reagent

A simple, rapid, and accurate method was developed for separation and preconcentration of trace levels of iron(III) and zinc(II) ions in environmental samples. Methyl‐2‐(4‐methoxy‐benzoyl)‐3‐(4‐methoxyphenyl)‐3‐oxopropanoylcarbamate (MMPC) has been proposed as a new complexing agent for Fe(III) and Zn(II) ions using solvent extraction prior to their determination by flame atomic absorption spectrometry (FAAS). Fe(III) and Zn(II) ions can be selectively separated from Fe(II), Pb(II), Co(II), Cu(II), Mn(II), Cr(III), Ni(II), Cd(II), Ag(I), Au(III), Pd(II), Cr(VI), and Al(III) ions in the solution by using the MMPC reagent. The analytical parameters such as pH, sample volume, shaking time, amount of MMPC reagent, volume of methyl isobutyl ketone (MIBK), effect of ionic strength, and type of back extractant were investigated. The recovery values for Fe(III) and Zn(II) ions were greater than 95% and the detection limits for Fe(III) and Zn(II) ions were 0.26 and 0.32 µg L^?1, respectively. The precision of the method as the relative standard deviation changed between 1.8 and 2.1%. Calibration curves have a determination coefficient (r²) of at least 0.997 or higher. The preconcentration factor was found to be 100. Accuracy of the method was checked by analyzing of a certified reference material and spiked samples. The developed method was applied to several matrices such as water, hair, and food samples.     

Pyritized mudstone and associated facies in the Permian–Triassic boundary of the Çürük Dağ section,Southern Turkey

This paper is the first study of pyritized mudstones (PM) in the Permian–Triassic (P–T) boundary section of the Çürük Da? (Taurus, Antalya Nappes, Turkey). The mudstones were generally formed as lensoidal-shaped layers or infill materials within nodular platform limestones (hardground). Normal marine fauna is diminished in the pyritized limestones, whereas tube-like microorganisms are apparently increased with the association of pyrite crystals consisting of both framboidal and cubic crystals. The total rock volumes are up to 50–60% clay minerals and are mainly made up of in situ kaolinite and subordinate mixed layer clays (illite–vermiculite). Kaolinite preferentially developed on feldspar crystals, sometimes covering ostracoda bivalves together with gypsum micronodules composed of fan-shaped gypsum crystals. The origin of the kaolinite is, in situ, directly related to feldspar dissolution via heterotrophic bacteria. Thus, kaolinite is found along with bacterial structures. Other mineralogical compositions include established quartz (mostly β-quartz), gypsum crystals (100–200 μm) glauconite and magnetite. Magnetite grains comprise a minor amount (1–2%) and show some bacterial-induced crystal orientations. Glauconite is formed as an accessory mineral that occurs as infill material in biogenic grains. On the other hand, some microspheres represented by a silica-dominated composition are only observed in scanning electron microscopes (SEM) studies under high magnification. Isotope values (d34S) obtained from the pyritized mudstones show an isotopic heterogeneity that suggests that the pyritized mudstone consists of at least two components, with different sulphur-concentrations and d34S values.     

Variations and Trends in Turkish Seasonal Heating and Cooling Degree-Days

The potential effect of climate change on energy demand is important especially for the developing and non-oil-producing countries. Cooling and heating degree-day (CDD and HDD) concepts are among the most significant meteorological variables related to residential energy consumption. This paper presents the spatial and temporal characteristics of Turkish seasonal CDD and HDD in the context of climate change. CDD and HDD are defined objectively by truncation of the temperature series at any constant base temperature level. This leads to surpluses and deficits as deviations. The surpluses are instances for cooling and the deficits for heating. Depending on temperature fluctuations, the degree-day statistics at any location show local and seasonal variations. In this study, regional variations of seasonal HDD and CDD are mapped for Turkey and their relations to local topography and climatic features are examined with conclusive interpretations. The sequential version of Mann–Kendall rank statisticis applied to demonstrate any existence of possible non-linear trends in accumulated HDD and CDD over the seasons. Spatially coherent and statistically significant trends of HDD and CDD appear in some regions of Turkey. In general, the sign of the trends is inconsistent with General Circulation Models (GCM) predictions.     

Informational decision support for risk reduction related to hailstorm in Oltenia region: Romania

This paper deals with the design of a system for decisional support dedicated to an anti-hail system. It is proposed a specific system for Romania anti-hail network, which completes the existing systems with specific information in order to identify the best solutions for both coordination and launch. The main topics refer to the system structure, information handled in the system and reconstruction of a signal based on Bayes criterion. The system comprises two main components: a subsystem of launch decision and a subsystem for assisting the launch decision. In order to achieve this system, the following important issues are considered: the use of communication via GPRS, monitoring the parameters throughout all operating period, log-values, status and alarms, operator actions logs, friendly graphical interface and the generation of tabular and graphical reports for any period. The system enables an increased efficiency by shortening the time for action, a good organization and a high degree of security.     

40Ar–39Ar dating, whole-rock and Sr–Nd–Pb isotope geochemistry of post-collisional Eocene volcanic rocks in the southern part of the Eastern Pontides (NE Turkey): implications for magma evolution in extension-induced origin

The Eocene volcano-sedimentary units in the southern part of the Eastern Pontides (NE Turkey) are confined within a narrow zone of east–west trending, semi-isolated basins in Bayburt, Gümü?hane, ?iran and Alucra areas. The volcanic rocks in these areas are mainly basalt and andesite through dacite, with a dominant calc-alkaline to rare tholeiitic tendency. ⁴⁰Ar–³⁹Ar dating of these volcanic rocks places them between 37.7 ± 0.2 and 44.5 ± 0.2 Ma (Middle Eocene). Differences in the major and trace element variations can be explained by the fractionation of clinopyroxene ± magnetite in basaltic rocks and that of hornblende + plagioclase ± magnetite ± apatite in andesitic rocks. Primitive mantle-normalized multi-element variations exhibit enrichment of large-ion lithophile elements and to a lesser extent, of light rare earth elements, as well as depletion of high field strength elements, thus revealing that volcanic rocks evolved from a parental magma derived from an enriched mantle source. Chondrite-normalized rare earth element patterns of the aforementioned volcanic rocks resemble each other and are spoon-shaped with low-to-medium enrichment (La_N/Lu_N = 2–14), indicating similar spinel lherzolitic mantle source(s). Sr, Nd and Pb isotopic systematics imply that the volcanic rocks are derived from a subduction-modified subcontinental lithospheric mantle. Furthermore, post-collisional thickened continental crust, lithospheric delamination and a subduction-imposed thermal structure are very important in generating Tertiary magma(s). The predominantly calc-alkaline nature of Eocene volcanic rocks is associated with increasing geodynamic regime-extension, whereas tholeiitic volcanism results from local variations in the stress regime of the ongoing extension and the thermal structure, as well as the thickness of the crust and the mantle-crust source regions. Based on volcanic variety and distribution, as well as on petrological data, Tertiary magmatic activity in Eastern Pontides is closely related to post-collisional thinning of the young lithosphere, which, in turn, is caused by extension and lithospheric delamination after collisional events between the Tauride–Anatolide Platform and the Eurasian Plate.