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Application of Multivariate Statistical Techniques for Characterization of Groundwater Quality in the Coastal Aquifer of Nador,Tipaza (Algeria) 总被引:1,自引:0,他引:1
Abdelkader Bouderbala Boualem Remini Abdelamir Saaed Hamoudi Antonio Pulido-Bosch 《Acta Geophysica》2016,64(3):670-693
The study focuses on the characterization of the groundwater salinity on the Nador coastal aquifer (Algeria). The groundwater quality has undergone serious deterioration due to overexploitation. Groundwater samplings were carried out in high and low waters in 2013, in order to study the evolution of groundwater hydrochemistry from the recharge to the coastal area. Different kinds of statistical analysis were made in order to identify the main hydrogeochemical processes occurring in the aquifer and to discriminate between different groups of groundwater. These statistical methods provide a better understanding of the aquifer hydrochem-istry, and put in evidence a hydrochemical classification of wells, showing that the area with higher salinity is located close to the coast, in the first two kilometers, where the salinity gradually increases as one approaches the seaside and suggests the groundwater salinization by sea-water intrusion. 相似文献
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Nabil Sultan Antonio Cattaneo Jean-Claude Sibuet Jean-Luc Schneider the Sumatra Aftershocks team 《International Journal of Earth Sciences》2009,98(4):823-837
The swath bathymetric data acquired during the “Sumatra Aftershocks” cruise from the Sunda trench in the Indian Ocean to the
north of the Sumatra Island imaged several scars and deposits. In situ pore pressure measurements using the Ifremer piezometer
and coring demonstrate that high excess pore pressure and sediment deformation was generated by a recent event in the scar
of the slope failure zone identified by J.T. Henstock and co-authors. This excess pore pressure is localized in the upper
sedimentary layers and is not related to an interplate subduction process. Numerical simulations of the hydrological system
that take into account the hydro-mechanical properties of the upper sediment layer show that the excess pore pressure and
sediment deformations could be generated at the time of the December 26, 2004 Great Sumatra Earthquake.
The Sumatra Aftershocks team: J.-C. Sibuet, S. Singh, R. Apprioual, N.C. Aryanto, J. Begot, A. Cattaneo, A.P.S. Chauchan,
R. Creach, J. Crozon, A. Domzig, N. Falleau, D. Graindorge, F. Harmegnies, Y. Haryadi, F. Klingelhoffer, S.K. Kolluru, J.-Y.
Landuré, C. Le Lann, J. Malod, A. Normand, G. Oggian, C. Rangin, D. Restunin Galih, J.-L. Schneider, N. Sultan, M. Taufik,
M. Umber and H. Yamaguchi. 相似文献
980.
Hélène Balcone‐Boissard Agnès Michel Benoît Villemant 《Geostandards and Geoanalytical Research》2009,33(4):477-485
Concentrations of halogens (fluorine, chlorine, bromine and iodine) were determined in six geochemical reference materials (BHVO‐2, GS‐N, JG‐1, JR‐1, JB‐1b, JB‐2). Halogens were first extracted from powdered samples using a pyrohydrolysis technique, then hydrolysis solutions were analysed by ion chromatography for F and Cl and inductively coupled plasma‐mass spectrometry for Br and I. The detection limits in solutions were 100 μg l?1 for both F and Cl and 10 ng l?1 for Br and I. Considering the extraction procedure, performed on a maximum of 500 mg of sample and producing 100 ml of pyrohydrolysis solution, detection limits in rock samples were 20 mg kg?1 for F and Cl and 2 μg kg?1 for Br and I. The mean analytical errors on the studied composition ranges were estimated at 10 mg kg?1 for F and Cl, 100 μg kg?1 for Br and 25 μg kg?1 for I. The concentration values, based on repeated (generally > 10) sample analysis, were in good agreement generally with published values and narrowed the mean dispersion around mean values. Large dispersions are discussed in terms of samples heterogeneity and contaminations during sample preparation. Basaltic RMs were found to be more suitable for studies of halogen compositions than differentiated rock material, especially granites – the powders of which were heterogeneous in halogens at the 500 mg level. 相似文献