1,720,969 research outputs found
Regime, dynamics and balance on the coast between Punta di li francesi and Capo Testa - northern sardinia
No full textGeochemistry of groundwater in an intensely urbanised karst area (Lusaka, Zambia)
No full textThe capital of Zambia Lusaka (about 2 million inhabitants) is built on a plateau where dolomitic marbles widely crop out. The carbonate formation hosts a very intensively exploited karstic groundwater resource. Considering the fast urban expansion and the lack of environmental control, this resource is in serious danger of pollution that could compromise the social and economical development of the capital. In this paper the geochemistry of the ground water is for the first time being analysed on the basis of a small number of samples taken in July 2001 in order to get a preliminary idea of the water quality. In some samples the concentrations of reduced nitrogen species and mercury exceed the guidelines proposed by the WHO for drinking water. Lusaka is a good example of the potential human impact on a vulnerable karst environment, and if no measures will be taken in the very near future, the quality of life in the city will be at serious risk
Coastal cartography of the quaternary deposits between cap Trahili and cap Trekala - South Kriti - Greece
No full textThe map of the coastal area between cap Trahili and cap Trekala (34 58‚ 00‰ the latitude North and 24° 54' 18 - 24° 58' 00 longitude East) is presented (1:10,000 scale map).
The survey map is the sheet 1:5.000 of the Greek M.G.S., and the preliminary geological cartography was made using the Geological sheet 1:50.000 scale map, by Greek geological institute with the aerial photos interpretation (flight B/W, 06.15.1995, 1: 8.000 scale map by Aeronautics Greek service) integrated by the survey effected on the field during the 2002 e 2003 Kriti expedition.
It is aimed mainly at locating and mapping the marine and transitional terraces in south Kriti coast.
From a methodological point of view, we followed the general criteria internationally adopted in coastal geological cartography. Considering the scale of the map and the difficulty in finding complete and uniform preliminary cartography, this work is different from the quoted bibliographical references, both in its legends and in some of the graphics related to practical requirements of the studied area. For some aspects (eg: graphics, explanations, information) the map is innovative especially as regards the use of digital data, low production costs and easier readability.
Cartographic restitution is prevalently referred to the coastal belt and reports the littoral, eolian, lacustrine and slopes forms, processes and deposits as well as those due to the flow of surface water or to the present coastal dynamics.
Moreover, with the help of photos printed at the edge of the map, the main geomorphological units are described: The show map extension the presence in outcrop of a geologic substrate with age comprised between the Mesozoic (Jurassic) and the Holocene on it has been recognized a series at least four main orders of marine terrace (from o to 25 metres above present sea level) represents from old palaeoabrasion platforms or palaeo beach deposits constituted from fossiliferous sands and gravels
Caratteri sedimentologici e dinamica delle spiagge e della piattaforma interna tra Capo Testa e Punta di li Francesi (Sardegna Settentrionale)
No full textThe results of a sedimentological study of the beaches and the inner shelf between Capo Testa and Punta di Li Francesi are herein reported. The aim of the work was to understand provenance, dispersion and sediments dynamics.
In the littoral parts oriented NE-SW (beaches of La Liccia, Rena Maiore, Buredaggia, Lu Litarroni, Naracu Nieddu, Lu Tuvunatu) a tendency of dispersion in direction NE-SW is evident from the analysis of the mean size along the shoreline, whereas this direction is opposite at a depth of 10 meters, according with the results of the study of the energy fluxes.
By mapping these data, dispersion controlled by clockwise circulation cells, whose form and extension are strongly conditioned by the conformation of the sea-floor, is delineated. In the physiographic units oriented NW-SE (beaches of Vignola, and La Colba) longshore transport oriented SE-NW prevails. Furthermore, in the sector comprised between Capo di M.ti Russu and Punta di Li Francesi, the sedimentological parameters indicate the existence of relict sediments at a bathymetric depth of 20 meters, that are scarcely related to the present dispersion.
By means of heavy mineral analysis lithogenic provenance of sediments was recognised to be from intrusive, volcanic and metamorphic rocks. A clear predominance of Epidote, in its most diffuse variety Pistacite, on Clinozoisite, as well as Amphiboles (Green Hornblende) and Pyroxenes was observed. Other minerals present in minor amounts are: Granates, Zircon, Picotite, Anatase, Andalusite, Staurolite, Sillimanite, Olivine, Tourmalin, Titanite, Rutile and Brookite, with low percentages of Apatite.
High percentages of heavy minerals are observed on the top of the dunes, diminishing on the berms and relatively increasing on the shoreline, if transects perpendicular to the beach are considered. In the submerged beach the highest concentrations have been observed at the foot of the bars. On the shoreline, in general, an increase in percentage can be observed from North to South
Caratteristiche sedimentologiche delle spiagge tra Capo Testa e Punta di li Francesi nord Sardegna
No full textGeochemistry of groundwater in an intensely urbanised karst area (Lusaka, Zambia)
No full textThe capital of Zambia Lusaka (about 2 million inhabitants) is built on a plateau where dolomitic marbles widely crop out. The carbonate formation hosts a very intensively exploited karstic groundwater resource. Considering the fast urban expansion and the lack of environmental control, this resource is in serious danger of pollution that could compromise the social and economical development of the capital. In this paper the geochemistry of the ground water is for the first time being analysed on the basis of a small number of samples taken in July 2001 in order to get a preliminary idea of the water quality. In some samples the concentrations of reduced nitrogen species and mercury exceed the guidelines proposed by the WHO for drinking water. Lusaka is a good example of the potential human impact on a vulnerable karst environment, and if no measures will be taken in the very near future, the quality of life in the city will be at serious risk
Caratteristiche sedimentologiche delle spiagge e della piattaforma interna tra Capo Testa e Punta Di Li Francesi (Sardegna settentrionale)
No full textIntegrated, sustainable touristic development of the karstic coastline of SW Sardinia
No full textcoastal kars
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
- …
