GPR Clutter Amplitude Processing to Detect Shallow Geological Targets
The analysis of clutter in A-scans produced by energy randomly scattered in some specific geological structures, provides information about changes in the shallow sedimentary geology. The A-scans are composed by the coherent energy received from reflections on electromagnetic discontinuities and the...
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| Format: | Article |
| Language: | English |
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MDPI AG
2018-01-01
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| Series: | Remote Sensing |
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| Online Access: | http://www.mdpi.com/2072-4292/10/1/88 |
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| author | Victor Salinas Naval Sonia Santos-Assunçao Vega Pérez-Gracia |
| author_facet | Victor Salinas Naval Sonia Santos-Assunçao Vega Pérez-Gracia |
| author_sort | Victor Salinas Naval |
| collection | DOAJ |
| description | The analysis of clutter in A-scans produced by energy randomly scattered in some specific geological structures, provides information about changes in the shallow sedimentary geology. The A-scans are composed by the coherent energy received from reflections on electromagnetic discontinuities and the incoherent waves from the scattering in small heterogeneities. The reflected waves are attenuated as consequence of absorption, geometrical spreading and losses due to reflections and scattering. Therefore, the amplitude of those waves diminishes and at certain two-way travel times becomes on the same magnitude as the background noise in the radargram, mainly produced by the scattering. The amplitude of the mean background noise is higher when the dispersion of the energy increases. Then, the mean amplitude measured in a properly selected time window is a measurement of the amount of the scattered energy and, therefore, a measurement of the increase of scatterers in the ground. This paper presents a simple processing that allows determining the Mean Amplitude of Incoherent Energy (MAEI) for each A-scan, which is represented in front of the position of the trace. This procedure is tested in a field study, in a city built on a sedimentary basin. The basin is crossed by a large number of hidden subterranean streams and paleochannels. The sedimentary structures due to alluvial deposits produce an amount of the random backscattering of the energy that is measured in a time window. The results are compared along the entire radar line, allowing the location of streams and paleochannels. Numerical models were also used in order to compare the synthetic traces with the field radargrams and to test the proposed processing methodology. The results underscore the amount of the MAEI over the streams and also the existence of a surrounding zone where the amplitude is increasing from the average value to the maximum obtained over the structure. Simulations show that this zone does not correspond to any particular geological change but is consequence of the path of the antenna that receives the scattered energy before arriving to the alluvial deposits. |
| first_indexed | 2024-04-11T18:03:31Z |
| format | Article |
| id | doaj.art-d45c436aadba43429a58b4fb3bfa3688 |
| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2024-04-11T18:03:31Z |
| publishDate | 2018-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-d45c436aadba43429a58b4fb3bfa36882022-12-22T04:10:25ZengMDPI AGRemote Sensing2072-42922018-01-011018810.3390/rs10010088rs10010088GPR Clutter Amplitude Processing to Detect Shallow Geological TargetsVictor Salinas Naval0Sonia Santos-Assunçao1Vega Pérez-Gracia2Geophysical Technician, World Sensing Barcelona, C/Viriat 47, 08014 Barcelona, SpainDepartment of Fluid Mechanics, Campus Diagonal Besòs—Edifici A (EEBE), Universitat Politècnica de Catalunya-BarcelonaTech, Av. Eduard Maristany, 16 08019 Barcelona, SpainDepartment of Strength of Materials and Structural Engineering, Campus Diagonal Besòs—Edifici A (EEBE), Universitat Politècnica de Catalunya-BarcelonaTech, Av. Eduard Maristany, 16 08019 Barcelona, SpainThe analysis of clutter in A-scans produced by energy randomly scattered in some specific geological structures, provides information about changes in the shallow sedimentary geology. The A-scans are composed by the coherent energy received from reflections on electromagnetic discontinuities and the incoherent waves from the scattering in small heterogeneities. The reflected waves are attenuated as consequence of absorption, geometrical spreading and losses due to reflections and scattering. Therefore, the amplitude of those waves diminishes and at certain two-way travel times becomes on the same magnitude as the background noise in the radargram, mainly produced by the scattering. The amplitude of the mean background noise is higher when the dispersion of the energy increases. Then, the mean amplitude measured in a properly selected time window is a measurement of the amount of the scattered energy and, therefore, a measurement of the increase of scatterers in the ground. This paper presents a simple processing that allows determining the Mean Amplitude of Incoherent Energy (MAEI) for each A-scan, which is represented in front of the position of the trace. This procedure is tested in a field study, in a city built on a sedimentary basin. The basin is crossed by a large number of hidden subterranean streams and paleochannels. The sedimentary structures due to alluvial deposits produce an amount of the random backscattering of the energy that is measured in a time window. The results are compared along the entire radar line, allowing the location of streams and paleochannels. Numerical models were also used in order to compare the synthetic traces with the field radargrams and to test the proposed processing methodology. The results underscore the amount of the MAEI over the streams and also the existence of a surrounding zone where the amplitude is increasing from the average value to the maximum obtained over the structure. Simulations show that this zone does not correspond to any particular geological change but is consequence of the path of the antenna that receives the scattered energy before arriving to the alluvial deposits.http://www.mdpi.com/2072-4292/10/1/88GPRclutterbackscatteringscattering modelling |
| spellingShingle | Victor Salinas Naval Sonia Santos-Assunçao Vega Pérez-Gracia GPR Clutter Amplitude Processing to Detect Shallow Geological Targets Remote Sensing GPR clutter backscattering scattering modelling |
| title | GPR Clutter Amplitude Processing to Detect Shallow Geological Targets |
| title_full | GPR Clutter Amplitude Processing to Detect Shallow Geological Targets |
| title_fullStr | GPR Clutter Amplitude Processing to Detect Shallow Geological Targets |
| title_full_unstemmed | GPR Clutter Amplitude Processing to Detect Shallow Geological Targets |
| title_short | GPR Clutter Amplitude Processing to Detect Shallow Geological Targets |
| title_sort | gpr clutter amplitude processing to detect shallow geological targets |
| topic | GPR clutter backscattering scattering modelling |
| url | http://www.mdpi.com/2072-4292/10/1/88 |
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