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A geophysical approach to the enviromental study of a coastal plain. Journal of Applied Geophysics, September 2003, Volume 68, Iusse 5, pp. 14461459 BALIA R.,GAVAUDO? E.,ARDAU F. & GHIGLIERI G. (2003)
No full textin the study of coastal plains affected by soil and water salination, a knowledge of several geological aspects, such as structural features, depth to basement, stratigraphy of sedimentary cover, relationships between the phreatic aquifer and underlying aquifers, and the latter's structure, is basic to gaining an adequate understanding of both the causes and possible evolution of salination. In this framework, geophysical techniques can play a very important role.
To improve the available geophysical information about the Muravera coastal plain, Sardinia, Italy, which is affected by severe soil and water salination, previously acquired electrical resistivity, reflection seismic and gravity data have been reprocessed, and a new seismic reflection survey has been conducted. Moreover, in order to give better support to the geological and hydrogeological interpretation of geophysical data, three boreholes were drilled. Reprocessed electrical data indicate the presence of a wide, electrically homogeneous low-resistivity zone associated with salination phenomena. Reprocessed reflection data provide useful information on the near-surface stratigraphy. The combined interpretation of resistivity and seismic results, supported by one calibration borehole, elucidates the relationships between the phreatic aquifer and the underlying confined aquifer. A new seismic reflection survey gives information on the depth to, and structure of, the Paleozoic basement, as well as on stratigraphic conditions of Pleistocene-Holocene sediments. Finally, the combined interpretation of seismic, gravity, and well data results in a geological section containing most of the information considered essential, such as the interface between Holocene alluvium and Pleistocene alluvium, the thickness of the latter, and the structure and composition of the Paleozoic basement.
The work as a whole shows how the combined application of geophysical techniques can in this specific situation provide wide-ranging and high-quality information that is essential for the realistic mathematical modeling of aquifer contamination, and can enable the rational planning of exploratory drillings
Geophysical approach to the environmental study of a coastal plain
No full textin the study of coastal plains affected by soil and water salination, a knowledge of several geological aspects, such as structural features, depth to basement, stratigraphy of sedimentary cover, relationships between the phreatic aquifer and underlying aquifers, and the latter's structure, is basic to gaining an adequate understanding of both the causes and possible evolution of salination. In this framework, geophysical techniques can play a very important role.
To improve the available geophysical information about the Muravera coastal plain, Sardinia, Italy, which is affected by severe soil and water salination, previously acquired electrical resistivity, reflection seismic and gravity data have been reprocessed, and a new seismic reflection survey has been conducted. Moreover, in order to give better support to the geological and hydrogeological interpretation of geophysical data, three boreholes were drilled. Reprocessed electrical data indicate the presence of a wide, electrically homogeneous low-resistivity zone associated with salination phenomena. Reprocessed reflection data provide useful information on the near-surface stratigraphy. The combined interpretation of resistivity and seismic results, supported by one calibration borehole, elucidates the relationships between the phreatic aquifer and the underlying confined aquifer. A new seismic reflection survey gives information on the depth to, and structure of, the Paleozoic basement, as well as on stratigraphic conditions of Pleistocene-Holocene sediments. Finally, the combined interpretation of seismic, gravity, and well data results in a geological section containing most of the information considered essential, such as the interface between Holocene alluvium and Pleistocene alluvium, the thickness of the latter, and the structure and composition of the Paleozoic basement.
The work as a whole shows how the combined application of geophysical techniques can in this specific situation provide wide-ranging and high-quality information that is essential for the realistic mathematical modeling of aquifer contamination, and can enable the rational planning of exploratory drillings
Hydrogeological and geophysical investigations for groundwater in the Arumeru District (Northen Tanzania)
No full textAlcune considerazioni su un caso di intervento antropico in un’area ad alto rischio idrogeologico
No full textAlcune considerazioni su un caso di intervento antropico in un’area ad alto rischio idrogeologico
No full textHydrogeological and geophysical investigations for groundwater in the Arumeru District (Northen Tanzania)
No full text
Assessment of the Capoterra coastal plain (Southern Sardinia, Italy) by means of hydrogeological and geophysical studies
No full textThe paper refers about combined geophysical and hydrogeological surveys carried out in a coastal plain in SW Sardinia (Italy). Concerning geophysical methods, reflection seismology, electrical resistivity soundings and TDEM were applied. These surveys confirm, with a high detail level, that the aquifers of the plain constitute a complex, multilayer system and that in the middle of the plain, due to presence of of thick impermeable Miocene materials, the probability of finding fresh water at a depth of less than 350-400 m is very low
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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