Wyniki wyszukiwania - BazTech

Ograniczanie wyników

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: lithological characteristics

Sortuj według:

Ogranicz wyniki do:

Effect of the Nile Aquifer Lithological Characteristics on Groundwater Chemistry in Assiut Governorate, Egypt

Saleem Hussein Ali, El-Tahlawi Mohamed R., Abo-El Kassem Mohamed, Boghdady Gamal Y.

Journal of Ecological Engineering

2019

Vol. 20, nr 6

73--83

The chemical composition of groundwater is affected by many features, including the impact caused by surrounding rocks. The Nile aquifer is surrounded by the calcareous structural plateau along the Assiut governorate on both sides. This paper aims at studying the effect of surrounding rocks on the chemical composition of groundwater in the Nile aquifer along the Assiut governorate. Fifty-five samples were taken from drinking water stations and irrigation wells in 2015, and then analyzed chemically in water and soil fertility laboratory located in the irrigation ministry in Assiut. Aquachem software package was used to determine the groundwater type and rock source deduction. Piper-trilinear diagram was plotted to show the hydrochemical facies. Furthermore, Gibbs diagram was applied to determine the correlation between water composition and aquifer lithological characteristics. The results revealed that nearly all of the groundwater samples drop in the water-rock interaction field. The results of rock source deduction show that the ratio of Cl to the sum of anions is less than 0.8 for all samples, concluding that the rock weathering is dominant. According to the criterion of TDS values, 78% of all the samples indicated that the carbonate weathering is prevalent; in turn, the ratio of Mg to Ca plus Mg shows that limestone-dolomite weathering is predominant. These results confirm that the calcareous structural plateau surrounding the Nile aquifer along the Assiut governorate has an effect on the groundwater chemistry by interacting between groundwater and limestone rocks which are the main component of the calcareous plateau.

Zmiany współczynnika filtracji gytii i kredy jeziornej na skutek ich etapowej konsolidacji : metodyka szacowania

Damicz J.

Przegląd Geologiczny

2015

Vol. 63, nr 3

155–-163

Lacustrine deposits, e.g. gyttja and lcustrine chalk, in natural conditions are weak soils from the engineering point of view. These soils under loading have large and long-lasting consolidation settlement. In the last years, these soils have been more often used as a subsoil, mainly for road and hydraulic engineering embankments. To predict the settlement, we have to know the strain and filtration parameters of the subsoil. The paper presents the results of coefficient permeability tests of gyttja and lacustrine chalk, performed in oedometer tests after following loading steps. The results have allowed obtaining downward but various trends of coefficient permeability changes in the consolidation process due to a decrease of void ratio. In general, the differences of trends are related to different types of gyttja. In the case of mineral-organic high-carbonate gyttja, three different decreasing trends were obtained. For these different trends, the causal relation was determined to the lithological impact factor. The lithological impact factor in the paper is proposed as the combination of main lithological characteristics.