scholarly journals Waterborne GPR survey for estimating bottom-sediment variability: A survey on the Po River, Turin, Italy

Geophysics ◽  
2009 ◽  
Vol 74 (4) ◽  
pp. B95-B102 ◽  
Author(s):  
Luigi Sambuelli ◽  
Corrado Calzoni ◽  
Manuele Pesenti
Keyword(s):  
Geophysical Survey ◽  
Amplitude Ratios ◽  
Water Conductivity ◽  
Po River ◽  
Sampling Campaign ◽  
Riverbed Sediments ◽  
Direct Sampling ◽  
Integrated Geophysical Survey ◽  
River Po ◽  
Sediment Variability

We conducted an integrated geophysical survey on a stretch of the river Po in order to check the GPR ability to discriminate the variability of riverbed sediments through an analysis of the bottom reflection amplitudes. We conducted continuous profiles with a [Formula: see text] GPR system and a handheld broadband EM sensor. A conductivity meter and a TDR provided punctual measurements of water conductivity, permittivity, and temperature. The processing and interpretation of the GEM-2 and GPR data were enhanced by reciprocal results and by integration with the punctual measurements of the EM properties of the water. We used a processing flow that improved the radargram images and preserved the amplitude ratios among the different profiles and the frequency content at the bottom reflection signal. We derived the water attenuation coefficient both from the punctual measurements using the Maxwell formulas and from the interpretation of the GPR data, finding an optimal matching between the two values. The GPR measurements provided maps of the bathymetry and of the bottom reflection amplitude. The high reflectivity of the riverbed, derived from the GPR interpretation, agreed with the results of the direct sampling campaign that followed the geophysical survey. The variability of the bottom-reflection-amplitudes map, which was not confirmed by the direct sampling, could also have been caused by scattering phenomena due to the riverbed clasts which are dimensionally comparable to the wavelength of the radar pulse.

scholarly journals Study of riverine deposits using electromagnetic methods at a low induction number

Geophysics ◽  
2007 ◽  
Vol 72 (5) ◽  
pp. B113-B120 ◽  
Author(s):  
Luigi Sambuelli ◽  
Salvatore Leggieri ◽  
Corrado Calzoni ◽  
Chiara Porporato
Keyword(s):  
Po River ◽  
Sampling Campaign ◽  
Electromagnetic Methods ◽  
Direct Sampling ◽  
Global Positioning ◽  
Ground Penetrating ◽  
Text Signal ◽  
Time Domain Reflectometer ◽  
Depth Of Investigation ◽  
River Bottom

We conducted electromagnetic (EM) profiles along the Po River in Turin, Italy. The aim of this activity was to verify the applicability of low-induction-number EM multifrequency soundings carried out from a boat in riverine surveys and to determine whether this technique, which is cheaper than air-carried surveys, could be used effectively to define the typology of sediments and to estimate the stratigraphy below a riverbed. We used a GEM-2 handheld broadband EM sensor operating with six frequencies to survey the investigated area. Ground-penetrating radar (GPR), a conductivity meter, and a time-domain reflectometer were used to estimate the bathymetry and to measure the EM properties of the water. A global positioning system, working in real-time kinematic mode, tracked the route of the boat with centimetric accuracy. We analyzed the induction number, the depth of investigation (DOI), and the sensitivity of our experimental setup by forward modeling — varying the water depth, frequency, and bottom-sediment resistivity. The simulations optimized the choice of the frequencies that could be used reliably for the interpretation. The [Formula: see text] signal had a DOI in the Po River water [Formula: see text] of [Formula: see text] and provided sediment resistivities higher than [Formula: see text]. We applied a bathymetric correction to the conductivity data using the water depths obtained from the GPR data. We plotted a map of the river bottom resistivity and compared this map to the results of a direct sediment sampling campaign. The resistivity values [Formula: see text] were compatible with the saturated gravel and pebbles in a sandy matrix, which resulted from direct sampling and with the known geology.

Integrated geophysical survey for 3D modelling of a coastal aquifer polluted by seawater

2013 ◽  
Vol 12 (1) ◽  
pp. 45-59 ◽  
Author(s):  
R. Martorana ◽  
L. Lombardo ◽  
N. Messina ◽  
D. Luzio
Keyword(s):  
Coastal Aquifer ◽  
3D Modelling ◽  
Geophysical Survey ◽  
Integrated Geophysical Survey

Case history: integrated geophysical survey at Katarínka Monastery (Slovakia)

2015 ◽  
Vol 13 (6) ◽  
pp. 585-599 ◽  
Author(s):  
D. Wilken ◽  
T. Wunderlich ◽  
H. Stümpel ◽  
W. Rabbel ◽  
R. Pašteka ◽  
...  
Keyword(s):  
Case History ◽  
Geophysical Survey ◽  
Integrated Geophysical Survey

scholarly journals The role of integrated geophysical survey methods in the assessment of archaeological landscapes: the case of Portus

2009 ◽  
Vol 16 (3) ◽  
pp. 154-166 ◽  
Author(s):  
Simon Keay ◽  
Graeme Earl ◽  
Sophie Hay ◽  
Stephen Kay ◽  
Jessica Ogden ◽  
...  
Keyword(s):  
Survey Methods ◽  
Geophysical Survey ◽  
Integrated Geophysical Survey ◽  
Geophysical Survey Methods

scholarly journals Cyperus-dominated vegetation in the eastern Po river

2020 ◽  
Vol 57 (2) ◽  
pp. 1-16
Author(s):  
Mauro Pellizzari
Keyword(s):  
Vegetation Types ◽  
Ecological Traits ◽  
Po River ◽  
Po Plain ◽  
New Association ◽  
Amaranthus Tuberculatus ◽  
Ephemeral Vegetation ◽  
River Po

The ephemeral vegetation dominated by Cyperus sp. pl. was surveyed and analyzed along the eastern trait of the Po River (Po Plain, Italy). Two formerly described communities were recognized: Cyperetum esculenti and Amaranthus tuberculatus-phytocoenon. A third greater cluster is assigned to a new association: Cyperetum micheliano-glomerati. It is characterized by Cyperus glomeratus, C. michelianus, C. odoratus and C. squarrosus, that have been detected on over 75 % of the relevés. The main floristic and ecological traits of these detected vegetation types are discussed.

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