A study of gross alpha and beta measurements for thermal springs in Central Anatolia,Turkey

A screening of natural radioactivity content has been carried out in thermal water samples collected from surrounding of Central Anatolia, Turkey. The concentration levels of gross alpha and beta of 19 different samples has been determined using the low background gas-flow proportional counter. The measured gross alpha and beta activities in waters range from 0.11 to 16 Bq/L and 0.10 to 16.9 Bq/L, respectively. The measured values of gross alpha and beta concentrations are compared to previous studies in the literature and recommend WHO guideline activity concentration. The data resulting from the measurement have been statistically analyzed.     

Lithologic mapping of Aja granitic batholiths,Ha’il,Saudi Arabia,using remote sensing

In this study, remote sensing, field and petrographic investigation were integrated for lithological mapping of different granitic masses in Aja complex of Ha’il, Saudi Arabia. The Landsat-8 data were processed to spectrally discriminate variations within rock types using band combinations, band ratioing and principal component analysis (PCA) techniques. Results showed that band combination of the principal components could potentially distinguish the different rock units of Aja complex than any other transform. Field observations and petrographic identification were performed to validate remotely sensing data and to map different rock units. Alkali granites were accurately recorded on the peripheries of Aja Mountain. The present study demonstrates that remote sensing techniques could provide useful tools for mapping economic rock types, particularly in well-exposed arid regions.     

The Effect of finite strain and deformation history of HALABAN area,eastern Arabian shield,Saudi Arabia

The present study aims to evaluate a relationship between the mineralogy and structural analysis in the Halaban area and to document the tectonic evolution of Halaban and Al Amar faults. The collected samples were taken from deformed granitiods rocks (such as granite, gneisses and tonalite), metasedimentary, metavolcanic, metagabbro and carbonate rocks are trend to NE-SW with low dip angle in the Halaban area. These samples were 8 from granite, 14 metagabbro, 6 metavolcanics, 5 tonalite, 6 metasedimentary, 10 gneisses and 8 carbonate rocks. Our results are described for the different axial ratios of deformed rocks as the following: XZ sections range from 1.10 to 4.60 in the Fry method and range from 1.70 to 2.71 in the Rf/? method. YZ sections range from 1.10 to 3.34 in the Fry method and range from 1.62 to 2.63 in the Rf/Phi method. In addition, XY sections range from 1 to 3.51 in the Fry method and range from 1 to 1.27 in the Rf/? method for deformed granite rocks, metasedimentry rocks, and metagabbro. The stretch axes for measured samples in the X direction axes (S_X) variety from 1.06 to 2.53 in the Fry method and vary from 1.20 to 1.45 in the Rf/? method. The values of the Y direction axes (S_Y) vary from 0.72 to 1.43 in the Fry method, which indicates contraction and extension in this direction and vary from 1.13 to 1.37 in the Rf/? method which indicates extension in this direction. Furthermore, the Z direction axes (SZ) varies from 0.09 to 0.89 in the Fry method and from 0.52 to 0.71 in the Rf/? method. The stretches axes in the Z direction (SZ) show a vertical shortening about 11% to 91% in the Fry method and show vertical shortening about 29% to 48% in the Rf/? method. The studied rock units are generally affected by brittle-ductile shear zones, which are sub-parallel to parallel NW or NNW trend. It assumed that different rock types of have similar deformation behavior. Based on these results, it is concluded that the finite strain is accumulated during the metamorphism after that was started the deformation by thrusting activity. The contacts between the different rock types were deformed during thrusting under semi-brittle to ductile deformation conditions by simple shear. A component of vertical shortening is also involved causing subhorizontal foliation in the Halaban area.     

Engineering risk assessment on water structures under climate change effects

The increase in the average temperature in the lower atmosphere caused by climate change triggers changes in various elements of the hydrological cycle at different scales depending on location in the world. Although numerous published studies are concerned with the effect of climate change on hydrological elements such as temperature, precipitation, evaporation, wind, and runoff, unfortunately, the performance of water engineering structures is not taken into consideration. Nevertheless, as an integral part of the whole water resources systems, engineering structures such as dams, canals, culverts, and wells are also subject to climate change impacts. This examines the performance of engineering structures by taking into account how climate change impacts on the risk assessment formulation. For this purpose, the risk concept is redefined and the climate change impact is taken into account by a factor dependent on the positive or negative slope of the trend from the historical record. The risk levels are revised for 10-year, 50-year, and 100-year return periods. The application of the proposed methodology is given for precipitation records for three different meteorological stations in the southeastern European province of Turkey and for the same number of stations from central east-west belt over Saudi Arabia. It is observed that including the climate change factor in the risk calculation formulation generally leads to an increase in the return period and in the risk compared to conventional calculations. Therefore, it is recommended that rather than using the standard risk formulation, the simple, effective climate change risk approach, as suggested in this paper, be applied to future water engineering structure designs.     

Seismic hazard assessment and rheological implications: a case study selected for cities of Saudi Arabia along the eastern coast of Red Sea

A probabilistic approach is used to evaluate the seismic hazard for 12 strategic cities in Saudi Arabia along the eastern coast of Red Sea. The focal depth variations controlled by rheological characteristics are taken into account for hazard calculations, and its creditability is tested through sensitivity analysis for hazard results. This study presents a neo-probabilistic seismic hazard assessment methodology in which the focal depth distribution of earthquakes within seismogenic layer is divided into three depth slices. These depth slices are based upon rheological characteristic of seismogenic layer. The hazard results are obtained using this depth-slice methodology and conventional approach in which uniform distribution of seismicity within seismogenic layer is assumed. The sensitivity analysis culminated in underestimation of hazard values in higher frequencies for uniform distribution of seismicity within seismogenic layer. Foregoing the observations recorded above, it can be concluded that the exploitation of depth-slices biased by the rheology to calculate hazard is relatively preferable in the situations demanding safety measures.     

The importance of water in the ecosystem and marine crisis in the gulf region

Conclusions As developing countries expand both agricultural and industrial activities over the coming decade, sensitive management of the limited available freshwater resources will become increasingly important. If their supplies consist solely of ground water, then some water deficit countries could end up by mining a non-renewable resource as it takes many thousands of years to replenish deep fossil groundwater stocks. Conservation and careful husbandry of existing stocks must therefore be carried out if the growing human populations of arid lands are to be protected from famine and poverty.The arid zones may provide more than sufficient food in a sustainable system despite the harsh natural conditions. In arid areas rainfall is low, biological cycling is limited by low soil moisture and evapotranspiration is high. The absence of leaching by infiltration results in a large active pool of nutrients and the addition of water by irrigation allows this potential fertility to be realised. Given the high insolation of desert lands and a man-made continuous water supply it is possible to obtain 2–4 crop harvest a year. However, the success of any future development is ultimately in the hands of the governments who control the management of water resources.Until recently pollution of the sea was relatively localised. It has now become a problem globally around coasts and even affects the open ocean. Enclosed and semi-enclosed seas are most vulnerable to degradation of their ecosystems and the Golf region has proved to be no exception to this, sensitivity exacerbated by weak currents and political instability leading to increasing oil pollution.The pollution in the Gulf is at its most harmful in the biologically diverse and productive areas around coastlines where pollution tends to concentrate and where human welfare is also most at risk. The outbreak of cholera and other waterborne disease in Iraq immediately following the Gulf war highlights the exceptional reliance people throughout the Gulf States must place of fresh water supplies. Continuing political instability in the region and its associated environmental damage will not, therefore, only threaten wildlife or fisheries but may threaten human welfare as water supplies are limited or decline in quality and industry, agriculture and health all suffer the consequences.     

Alluvium thickness and stream order relationships in Wadi Al-Khanagah basin,Central Saudi Arabia

Conclusion This study represents a step forward in understanding the geomorphology of Wadi Al-Khanagah basin, especially the relationship between depositional landforms and drainage basin morphometry. Besides it has drawn the attention to the importance of establishing the relationships between landforms for rapid applied hydrogeomorphological studies in areas lacking systematic data base. To conclude, the established relationships between alluvium thickness and stream order in Wadi Al-Khanagah basin would give an adequate mean of predicting thickness of wadi alluvium and consequently the capacity of potential alluvium aquifers in the shield area of the Al-Quwayiyah region, in Central Saudi Arabia.     

Seasonal studies on cadmium concentration and toxicity, oxygen consumption, digestive gland glycogen, and lipid in dog whelks collected at Aberystwyth, Wales

The concentration of cadmium in Nucella was investigated at different times of the year at one site. There was no significant difference in tissue cadmium at the times of the year investigated but tissue zinc was more variable. Accumulation and toxicity of cadmium were studied using 50–600 μg Cd l⁻¹ for 21 days. There was no significant seasonal difference in the rate of cadmium uptake but mortality appeared to vary with the season. Nucella did not survive 21 days at 600 μg Cd l⁻¹, but at lower concentrations 50–100 μg Cd l⁻¹ all survived.

Although there was significant drop in oxygen consumption between 7 and 14 days it did not appear to be related to the cadmium exposure. Glycogen levels on the other hand showed a decrease after cadmium treatment, while lipid values remained unchanged. Results are discussed in relation to energy source, season, and adaptation to the environment.