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51.
The study area is in the southeastern part of the city of Elaz between 38°17–38°43 latitudes and 38°36–39°07 longitudes. Formations of Paleozoic, Mesozoic and Cenozoic age comprise confined and unconfined aquifers. Unconfined aquifers are represented by Na-Cl and Na-HCO3 type waters while confined aquifers are characterized by Ca-HCO3, Mg-HCO3 and Na-HCO3 type waters. Due to sodium pollution, as a result of irrigation from waters of Hazar lake in the plain, as well as intense use of artificial fertilizer and improper storage of animal fertilizers, NH4-N, NO3-N and total PO4-P pollution are detected in waters of the unconfined aquifer. Organic material contents in waters of well nos. S27, S29 and S32 completed in the unconfined aquifer are above 3.5 mg/l of Turkish Standard Institute (TSE), (266) standard. In confined aquifers, total PO4-P pollution in four wells and NH4-N pollution in three wells were observed to be above the TSE (266) standard. 相似文献
52.
Jacek?Majorowicz Jan??afanda Torun- Working Group 《International Journal of Earth Sciences》2008,97(2):307-315
High-precision temperature measurements were carried out up to a depth of 2,930 m in the 5.5-km-deep well Torun-1, 26 years
after completion of drilling. The temperature log provides equilibrium thermal state information for the Polish Lowland at
the western margin of the Precambrian craton. Geothermal gradient calculated from the equilibrium temperature log, together
with estimates of thermal conductivity from ‘net rock’ geophysical well logging analysis and available core measurements,
yields heat flow in the range 50–60 mW/m2 below 2-km depth. Heat flow of 50 mW/m2 plus ∼10 mW/m2 generated within thick sediments and highly metamorphosed sedimentary wedge is typical for the western margin of the Precambrian
East European craton. Heat-flow variations with depth can be explained by a model of surface-temperature changes >10°C (glaciation
to Holocene).
Torun-1 Working Group: Marta Wróblewska, Jacek Majorowicz, Jan Szewczyk, Jan Šafanda, Vladimír Cermák 相似文献
53.
Ond?ej?LhotkaEmail authorView author&#;s OrcID profile Jan?Kysely Ale??Farda 《Theoretical and Applied Climatology》2018,131(3-4):1043-1054
The study examines climate change scenarios of Central European heat waves with a focus on related uncertainties in a large ensemble of regional climate model (RCM) simulations from the EURO-CORDEX and ENSEMBLES projects. Historical runs (1970–1999) driven by global climate models (GCMs) are evaluated against the E-OBS gridded data set in the first step. Although the RCMs are found to reproduce the frequency of heat waves quite well, those RCMs with the coarser grid (25 and 50 km) considerably overestimate the frequency of severe heat waves. This deficiency is improved in higher-resolution (12.5 km) EURO-CORDEX RCMs. In the near future (2020–2049), heat waves are projected to be nearly twice as frequent in comparison to the modelled historical period, and the increase is even larger for severe heat waves. Uncertainty originates mainly from the selection of RCMs and GCMs because the increase is similar for all concentration scenarios. For the late twenty-first century (2070–2099), a substantial increase in heat wave frequencies is projected, the magnitude of which depends mainly upon concentration scenario. Three to four heat waves per summer are projected in this period (compared to less than one in the recent climate), and severe heat waves are likely to become a regular phenomenon. This increment is primarily driven by a positive shift of temperature distribution, but changes in its scale and enhanced temporal autocorrelation of temperature also contribute to the projected increase in heat wave frequencies. 相似文献
54.
Spatial and temporal variations of aridity indices in Iraq 总被引：1，自引：0，他引：1
Nermin??arlakEmail author Omar?M.?A.?Mahmood Agha 《Theoretical and Applied Climatology》2018,132(1-2):89-101
In this paper, a nonhydrostatic Weather Research and Forecasting (WRF) model has been used to simulate the extreme precipitation event of 25 November 2009, over Jeddah, Saudi Arabia. The model is integrated in three nested (27, 9, and 3 km) domains with the initial and boundary forcing derived from the NCEP reanalysis datasets. As a control experiment, the model integrated for 48 h initiated at 0000 UTC on 24 November 2009. The simulated rainfall in the control experiment depicts in well agreement with Tropical Rainfall Measurement Mission rainfall estimates in terms of intensity as well as spatio-temporal distribution. Results indicate that a strong low-level (850 hPa) wind over Jeddah and surrounding regions enhanced the moisture and temperature gradient and created a conditionally unstable atmosphere that favored the development of the mesoscale system. The influences of topography and heat exchange process in the atmosphere were investigated on the development of extreme precipitation event; two sensitivity experiments are carried out: one without topography and another without exchange of surface heating to the atmosphere. The results depict that both surface heating and topography played crucial role in determining the spatial distribution and intensity of the extreme rainfall over Jeddah. The topography favored enhanced uplift motion that further strengthened the low-level jet and hence the rainfall over Jeddah and adjacent areas. On the other hand, the absence of surface heating considerably reduced the simulated rainfall by 30% as compared to the observations. 相似文献
55.
Mountain streams with their tributary torrents build the upper part of the fluvial network. They are important regarding the transfer of sediment from headwaters to lower basins. Channels are typically steep with wide grain size distributions, ranging from fine sand up to large boulders, and a stabilized bed surface. Mountain streams often are supply-limited with respect to mobile bed load, which needs to be addressed when bed load transport equations are applied to such streams. To better understand supply limitation, laboratory experiments highlighting the effect of bed load supply on incipient motion and bed load transport rate are discussed. Experimental tests were done in which fine bed load was supplied to a previously armored channel bed, with flow conditions ranging from one-third to twice the critical dis-charge for the bed surface. At flows not exceeding the critical discharge, the time series of the bed load transport rate at the downstream model boundary featured consistent patterns which are attributed to distinct phases: (i) a temporal lag, (ii) an equilibrium state, and (iii) a post-supply phase. Bed load transport occurred even at flows distinctly below that for incipient motion of the bed surface. But, with the mass of total bed load outflow approaching the supply amount, the mass did not exclusively consist of supplied grains. The coarser the supplied bed load, the more sediment was mobilized from the bed surface. At higher flows, processes differed. Total bed load outflow exceeded the supply amount and the break-up of the armor layer caused a refining of the bed surface. 相似文献
56.
Seda??alap-Ay?aEmail authorView author&#;s OrcID profile Piotr?Jankowski 《Stochastic Environmental Research and Risk Assessment (SERRA)》2018,32(9):2699-2719
Land use evaluation involves careful consideration of several environmental factors and their relative importance quantified by factor weights. Local multi-criteria evaluation provides a mechanism for computing factor (criteria) weights within local neighborhoods that capture spatial heterogeneity and contribute to more accurate evaluation results. The accuracy of results, however, is tempered by the potential uncertainty of criteria weights. The paper presents a spatially explicit approach to uncertainty and sensitivity analysis of local criteria weights and modeling scale on the variability of model output. The efficacy of the approach is presented on the example of Environmental Benefit Index (EBI) model used by the U.S. Department of Agriculture Conservation Reserve Program (CRP) to select environmentally sensitive agricultural areas for conservation. The uncertainty analysis resulted in identifying robust areas for CRP selection characterized by high suitability and low uncertainty. The sensitivity analysis focused on the next-best group of candidates characterized by high suitability and high uncertainty. The results show that there is a relationship between spatial heterogeneity, data representation scale, and the level of uncertainty in the results of EBI model. The sensitivity of model output can be attributed to both the uncertainty of criteria weights and the modeling scale. A potential practical value of this approach is the improved analytical support for land suitability evaluation requiring a consideration of sub-optimal land units (high suitability/high uncertainty). Also, this approach can guide modelling effort by allowing the analyst to visualize spatial distribution and patterns of model output uncertainty and focus data collection on influential model input factors. 相似文献
57.
Ju??KocijanEmail authorView author&#;s OrcID profile Dejan?Gradi?ar Martin?Stepan?i? Marija?Zlata?Bo?nar Bo?tjan?Gra?i? Primo??Mlakar 《Stochastic Environmental Research and Risk Assessment (SERRA)》2018,32(6):1759-1770
This paper highlights the problem of step-length selection for the one-step-ahead prediction of ozone called the data time interval. This is done using a case study-based comparison of two approaches for predicting the maximum daily values of tropospheric ozone. The first approach is the 1-day-ahead prediction and the second is the prediction of the maximum values based on a multi-step-ahead iteration of 1-h predictions. Gaussian process modelling is utilised for this comparison. In particular, evolving Gaussian-process models are used that update on-line with the incoming measurement data. These sorts of models have been successfully used in the past for the prediction of ozone pollution. This paper contributes an assessment of the way that the maximum ozone values are predicted. A comparison of the daily maximum ozone values forecasted by a model based on 1-day-ahead predictions with those obtained by iterated 1-h-ahead predictions of the ozone with predictions at predetermined hours of the day is given. The forecast results are in favour of the on-line model based on hourly predictions when approaching closer to the real maximum values of ozone, and in favour of the daily predictions when they are made on a daily basis. 相似文献
58.
Slow long-duration events (SLDEs) are flares characterized by the long duration of their rising phase. In many such cases the impulsive phase is weak without typical short-lasting pulses. Instead, smooth, long-lasting hard X-ray (HXR) emission is observed. We analyzed hard X-ray emission and morphology of six selected SLDEs. In our analysis we utilized data from the RHESSI and GOES satellites. The physical parameters of HXR sources were obtained from imaging spectroscopy and were used for the energy balance analysis. The characteristic decay time of the heating rate, after reaching its maximum value, is very long, which explains the long rising phase of these flares. 相似文献
59.
Yal??n?E.?ErsoyEmail author Cahit?Helvac? Martin?R.?Palmer 《Contributions to Mineralogy and Petrology》2012,163(3):379-401
The western Anatolian volcanic province formed during Eocene to Recent times is one of the major volcanic belts in the Aegean–western
Anatolian region. We present new chemical (whole-rock major and trace elements, and Sr, Nd, Pb and O isotopes) and new Ar/Ar
age data from the Miocene volcanic rocks in the NE–SW-trending Neogene basins that formed on the northern part of the Menderes
Massif during its exhumation as a core complex. The early-middle Miocene volcanic rocks are classified as high-K calc-alkaline
(HKVR), shoshonitic (SHVR) and ultrapotassic (UKVR), with the Late Miocene basalts being transitional between the early-middle
Miocene volcanics and the Na-alkaline Quaternary Kula volcanics (QKV). The early-middle Miocene volcanic rocks are strongly
enriched in large ion lithophile elements (LILE), have high 87Sr/86Sr(i) (0.70631–0.71001), low 143Nd/144Nd(i) (0.512145–0.512488) and high Pb isotope ratios (206Pb/204Pb = 18.838–19.148; 207Pb/204Pb = 15.672–15.725; 208Pb/204Pb = 38.904–39.172). The high field strength element (HFSE) ratios of the most primitive early-middle Miocene volcanic rocks
indicate that they were derived from a mantle source with a primitive mantle (PM)-like composition. The HFSE ratios of the
late Miocene basalts and QKV, on the other hand, indicate an OIB-like mantle origin—a hypothesis that is supported by their
trace element patterns and isotopic compositions. The HFSE ratios of the early-middle Miocene volcanic rocks also indicate
that their mantle source was distinct from those of the Eocene volcanic rocks located further north, and of the other volcanic
provinces in the region. The mantle source of the SHVR and UKVR was influenced by (1) trace element and isotopic enrichment
by subduction-related metasomatic events and (2) trace element enrichment by “multi-stage melting and melt percolation” processes
in the lithospheric mantle. The contemporaneous SHVR and UKVR show little effect of upper crustal contamination. Trace element
ratios of the HKVR indicate that they were derived mainly from lower continental crustal melts which then mixed with mantle-derived
lavas (~20–40%). The HKVR then underwent differentiation from andesites to rhyolites via nearly pure fractional crystallization
processes in the upper crust, such that have undergone a two-stage petrogenetic evolution. 相似文献
60.
Underground mining hazard map including building site categories in an area affected by underground mining activities 总被引：1，自引：1，他引：0
Marian?Marschalko I??k?YilmazEmail author David?Lamich Martin?Bednárik 《Environmental Earth Sciences》2014,72(7):2655-2666
The objective of the paper is generation of an underground mining hazard map. The method applied to create the map is based on five categories of areas with different characters of underground mining influence making use of the so-called building site categories. The individual areas with different groups represent various suitability or unsuitability for founding new structures in such influenced territories. They will also reflect a higher or lower degree of influence on already existing structures. Areas affected by underground mining of category V are suitable without any significant restrictions. Areas of the medium category represent influence of building site categories III and IV with economically acceptable measures for founding engineering purposes. The last type is areas with high influence in the category I and II and they are clearly unsuitable for new development. Structures may be founded there in exceptional cases only. This methodology was applied on four map sheets in 1:10,000 scale in a coal mining region in the town of Karviná and its environs in the direction to the City of Ostrava (Czech Republic). Extensive changes caused by underground mining have been identified in the study area and the implementation of the suggested maps may help to deal with the issue in terms of land development by means of land use planning. 相似文献