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Rio Indra Sakti Pasaribu - One of the best experts on this subject based on the ideXlab platform.
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APLIKASI METODE GEORADAR UNTUK ANALISIS LAPISAN SEDIMEN BAWAH PERMUKAAN DI SUAK SUKE DAN SUAK PANTE BREUH, SAMATIGA, ACEH BARAT
'Fakultas MIPA Universitas Negeri Makassar', 2019Co-Authors: Rio Indra Sakti PasaribuAbstract:Kajian tentang Sedimen bawah permukaan telah dilakukan dengan metode Ground Penetrating Radar di desa Suak Seuke dan Suak Pante Breuh, kecamatan Samatiga, Aceh Barat. Tujuan dari penelitian ini adalah untuk mendeteksi keberadaan lapisan sedimen yang terendapkan di area penelitian dengan menggunakan metode Ground Penetrating Radar (GPR) MALA 240 MHz. Pengukuran dilakukan dalam empat lintasan yang panjangnya 160 m, 210 m, 180 m dan 120 m yang tegak lurus dengan garis pantai. Data pengukuran yang diperoleh berupa reflektor dalam bentuk Radargram yang menggambarkan penampang bawah permukaan. Pengolahan data dilakukan dengan menggunakan software GRED. Data ini kemudian dikoreksi dengan filter move start time, background removal, vertical bandpass filter (td), linear gain, dan smooth gain secara berurutan. Hasil interpretasi menunjukkan bahwa struktur perlapisan bawah permukaan terbedakan atas 3 lapisan sampai kedalaman 3 m untuk setiap lintasan. Lapisan paling atas terdiri dari lapisan lempung (clay), lapisan kedua terdiri dari pasir lempung (sandy clay), kemudian lapisan lempung dilapisan ketiga. Berdasarkan beda penampang reflektor pada Radargram menunjukkan adanya struktur perlapisan sedimen bawah permukaan.Kata Kunci : Ground Penetrating Radar (GPR), Sedimentasi, Radargram, Aceh BaratBanda Ace
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APLIKASI METODE GEORADAR UNTUK ANALISIS LAPISAN SEDIMEN BAWAH PERMUKAAN DI SUAK SEUKE DAN SUAK PANTE BREUH, SAMATIGA, ACEH BARAT
2024Co-Authors: Rio Indra Sakti PasaribuAbstract:Kajian tentang Sedimen bawah permukaan telah dilakukan dengan metode Ground Penetrating Radar di desa Suak Seuke dan Suak Pante Breuh, kecamatan Samatiga, Aceh Barat. Tujuan dari penelitian ini adalah untuk mendeteksi keberadaan lapisan sedimen yang terendapkan di area penelitian dengan menggunakan metode Ground Penetrating Radar (GPR) MALA 240 MHz. Pengukuran dilakukan dalam empat lintasan yang panjangnya 160 m, 210 m, 180 m dan 120 m yang tegak lurus dengan garis pantai. Data pengukuran yang diperoleh berupa reflektor dalam bentuk Radargram yang menggambarkan penampang bawah permukaan. Pengolahan data dilakukan dengan menggunakan software GRED. Data ini kemudian dikoreksi dengan filter move start time, background removal, vertical bandpass filter (td), linear gain, dan smooth gain secara berurutan. Hasil interpretasi menunjukkan bahwa struktur perlapisan bawah permukaan terbedakan atas 3 lapisan sampai kedalaman 3 m untuk setiap lintasan. Lapisan paling atas terdiri dari lapisan lempung (clay), lapisan kedua terdiri dari pasir lempung (sandy clay), kemudian lapisan lempung dilapisan ketiga. Berdasarkan beda penampang reflektor pada Radargram menunjukkan adanya struktur perlapisan sedimen bawah permukaan.Kata Kunci : Ground Penetrating Radar (GPR), Sedimentasi, Radargram, Aceh Bara
Bukhori Maha - One of the best experts on this subject based on the ideXlab platform.
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ANALISIS GELOMBANG GEORADAR UNTUK SSTUDI PERLAPISAN SEDIMEN PANTAI LAMPANAH LEUNGAH, ACEH BESAR
'Fakultas MIPA Universitas Negeri Makassar', 2018Co-Authors: Bukhori MahaAbstract:ABSTRAKKajian sedimentasi memerlukan gambaran awal kondisi perlapisan material bawah permukaan sebelum dilakukan eksplorasi lebih lanjut. Pada penelitian ini telah dilakukan pengukuran metode Ground Penetrating Radar (GPR) di kawasan pantai Desa Lampanah Leungah, Mukim Lampanah, Kecamatan Seulimeum, Kabupaten Aceh Besar untuk mengetahui struktur perlapisan pantai dengan pola refleksi pada tampilan Radargram. Pengukuran data GPR dilakukan pada 7 lintasan, 5 lintasan arah Utara-Selatan tegak lurus dengan garis pantai, sedangkan 2 lintasan dibuat memotong kelima lintasan tersebut dalam arah Timur-Barat untuk validasi. Data pengukuran yang diperoleh berupa reflektor dalam bentuk Radargram yang menggambarkan penampang bawah permukaan. Pengolahan data dilakukan dengan menggunakan software GRED. Hasil analisis menunjukkan bahwa struktur perlapisan bawah permukaan terbedakan atas 4 lapisan sampai kedalaman 6 m. Lapisan paling atas terdiri dari pasir dan tanah liat, kemudian diikuti oleh lapisan pasir, kemudian lapisan pasir dan kerikil, dan lapisan pasir, kerikil, serta batuan dasar dibawahnya. Kata kunci: Ground Penetrating Radar (GPR), perlapisan sedimen, RadargramABSTRACTStudy of sedimentation requires preliminary information of subsurface before further exploration planned. Ground Penetrating Radar (GPR) measurement were conducted in coastal area of Lampanah Leungah, Lampanah Mukim, Seulimeum District, Aceh Besar Regency, to study the layering structure of coastal area based on Radargram display. The GPR data were collected along 7 profiles; 5 profiles in North-South direction crossing to coastline and the profiles in East-West direction parallel to the coastline. The observed data displayed in the form reflectors as rdargram imaging cross-section of subsurface. Data processing were done using GRED software. The processed data show that the structures of the surface formed by 4 layers up to 6 m depth. The top layer consist of sand and clay deposits, followed by sand layer, sand and gravel, and the underlying bedrock.Keywords: Ground Penetrating Radar (GPR), Layering of sediments, RadargramBanda Ace
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ANALISIS GELOMBANG GEORADAR UNTUK SSTUDI PERLAPISAN SEDIMEN PANTAI LAMPANAH LEUNGAH, ACEH BESAR
2024Co-Authors: Bukhori MahaAbstract:ABSTRAKKajian sedimentasi memerlukan gambaran awal kondisi perlapisan material bawah permukaan sebelum dilakukan eksplorasi lebih lanjut. Pada penelitian ini telah dilakukan pengukuran metode Ground Penetrating Radar (GPR) di kawasan pantai Desa Lampanah Leungah, Mukim Lampanah, Kecamatan Seulimeum, Kabupaten Aceh Besar untuk mengetahui struktur perlapisan pantai dengan pola refleksi pada tampilan Radargram. Pengukuran data GPR dilakukan pada 7 lintasan, 5 lintasan arah Utara-Selatan tegak lurus dengan garis pantai, sedangkan 2 lintasan dibuat memotong kelima lintasan tersebut dalam arah Timur-Barat untuk validasi. Data pengukuran yang diperoleh berupa reflektor dalam bentuk Radargram yang menggambarkan penampang bawah permukaan. Pengolahan data dilakukan dengan menggunakan software GRED. Hasil analisis menunjukkan bahwa struktur perlapisan bawah permukaan terbedakan atas 4 lapisan sampai kedalaman 6 m. Lapisan paling atas terdiri dari pasir dan tanah liat, kemudian diikuti oleh lapisan pasir, kemudian lapisan pasir dan kerikil, dan lapisan pasir, kerikil, serta batuan dasar dibawahnya. Kata kunci: Ground Penetrating Radar (GPR), perlapisan sedimen, RadargramABSTRACTStudy of sedimentation requires preliminary information of subsurface before further exploration planned. Ground Penetrating Radar (GPR) measurement were conducted in coastal area of Lampanah Leungah, Lampanah Mukim, Seulimeum District, Aceh Besar Regency, to study the layering structure of coastal area based on Radargram display. The GPR data were collected along 7 profiles; 5 profiles in North-South direction crossing to coastline and the profiles in East-West direction parallel to the coastline. The observed data displayed in the form reflectors as rdargram imaging cross-section of subsurface. Data processing were done using GRED software. The processed data show that the structures of the surface formed by 4 layers up to 6 m depth. The top layer consist of sand and clay deposits, followed by sand layer, sand and gravel, and the underlying bedrock.Keywords: Ground Penetrating Radar (GPR), Layering of sediments, radargra
Coquet Yves - One of the best experts on this subject based on the ideXlab platform.
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Hydrodynamic parameters of a sandy soil determined by ground-penetrating radar inside a single ring infiltrometer
'Wiley', 2014Co-Authors: Léger Emmanuel, Saintenoy Albane, Coquet YvesAbstract:International audienceThis study shows how Mualem-van Genuchten (M-vG) parameters can be obtained from GPR data acquired during water infiltration from a single ring infiltrometer in the case of a sandy soil. Water content profiles were generated at various time steps using HYDRUS-1D, based on particular values of the M-vG parameters and were converted to dielectric permittivity profiles using the Complex Refractive Index Method. The GprMax suite of programs was used to generate Radargrams and to follow the wetting front progression in depth using the arrival time of the electromagnetic waves recorded by a ground-penetrating radar (GPR). Theoretically, the 1-D time convolution between reflectivity and GPR signal at any infiltration time step is related to the peak of the reflected signal recorded in the corresponding trace in the Radargram. We used this relationship to invert the M-vG parameters for constant and falling head infiltrations using the Shuffled Complex Evolution (SCE-UA) algorithm. The method is presented on synthetic examples and on experiments carried out for a sandy soil. The parameters inverted are compared with values obtained in laboratory on soil samples and with disk infiltrometer measurements
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Estimating Saturated Hydraulic Conductivity from Surface Ground-Penetrating Radar Monitoring of Infiltration
HAL CCSD, 2013Co-Authors: Léger Emmanuel, Saintenoy Albane, Coquet YvesAbstract:International audienceIn this study we used Hydrus-1D to simulate water infiltration from a ring infiltrometer. We generated water content profiles at each time step of infiltration, based on a particular value of the saturated hydraulic conductivity while knowing the other van Genuchten parameters. Water content profiles were converted to dielectric permittivity profiles using the Complex Refractive Index Method relation. We then used the GprMax suite of programs to generate Radargrams and to follow the wetting front using arrival time of electromagnetic waves recorded by a Ground-Penetrating Radar (GPR). Theoretically, the depth of the inflection point of the water content profile simulated at any infiltration time step is related to the peak of the reflected amplitude recorded in the corresponding trace in the Radargram. We used this relationship to invert the saturated hydraulic conductivity for constant and falling head infiltrations. We present our method on synthetic examples and on two experiments carried out on sand. We further discuss the possibility of estimating two other van Genuchten parameters, n and α, in addition to the saturated hydraulic conductivity
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Estimating Saturated Hydraulic Conductivity from Surface Ground-Penetrating Radar Monitoring of Infiltration
2013Co-Authors: Léger Emmanuel, Saintenoy Albane, Coquet YvesAbstract:In this study we used Hydrus-1D to simulate water infiltration from a ring infiltrometer. We generated water content profiles at each time step of infiltration, based on a particular value of the saturated hydraulic conductivity while knowing the other van Genuchten parameters. Water content profiles were converted to dielectric permittivity profiles using the Complex Refractive Index Method relation. We then used the GprMax suite of programs to generate Radargrams and to follow the wetting front using arrival time of electromagnetic waves recorded by a Ground-Penetrating Radar (GPR). Theoretically, the depth of the inflection point of the water content profile simulated at any infiltration time step is related to the peak of the reflected amplitude recorded in the corresponding trace in the Radargram. We used this relationship to invert the saturated hydraulic conductivity for constant and falling head infiltrations. We present our method on synthetic examples and on two experiments carried out on sand. We further discuss the possibility of estimating two other van Genuchten parameters, n and \alpha, in addition to the saturated hydraulic conductivity.Comment: 4th International Conference "HYDRUS Software Applications to Subsurface Flow and Contaminant Transport Problems," Praque : Czech Republic (2013
Yves Coquet - One of the best experts on this subject based on the ideXlab platform.
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Estimating Saturated Hydraulic Conductivity from Surface Ground-Penetrating Radar Monitoring of Infiltration
arXiv: Geophysics, 2013Co-Authors: Emmanuel Léger, Albane Saintenoy, Yves CoquetAbstract:In this study we used Hydrus-1D to simulate water infiltration from a ring infiltrometer. We generated water content profiles at each time step of infiltration, based on a particular value of the saturated hydraulic conductivity while knowing the other van Genuchten parameters. Water content profiles were converted to dielectric permittivity profiles using the Complex Refractive Index Method relation. We then used the GprMax suite of programs to generate Radargrams and to follow the wetting front using arrival time of electromagnetic waves recorded by a Ground-Penetrating Radar (GPR). Theoretically, the depth of the inflection point of the water content profile simulated at any infiltration time step is related to the peak of the reflected amplitude recorded in the corresponding trace in the Radargram. We used this relationship to invert the saturated hydraulic conductivity for constant and falling head infiltrations. We present our method on synthetic examples and on two experiments carried out on sand. We further discuss the possibility of estimating two other van Genuchten parameters, n and \alpha, in addition to the saturated hydraulic conductivity.
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Saturated hydraulic conductivity determined by on ground mono-offset Ground-Penetrating Radar inside a single ring infiltrometer
arXiv: Geophysics, 2013Co-Authors: Emmanuel Léger, Albane Saintenoy, Yves CoquetAbstract:In this study we show how to use GPR data acquired along the infiltration of water inside a single ring infiltrometer to inverse the saturated hydraulic conductivity. We used Hydrus-1D to simulate the water infiltration. We generated water content profiles at each time step of infiltration, based on a particular value of the saturated hydraulic conductivity, knowing the other van Genuchten parameters. Water content profiles were converted to dielectric permittivity profiles using the Complex Refractive Index Method relation. We then used the GprMax suite of programs to generate Radargrams and to follow the wetting front using arrival time of electromagnetic waves recorded by a Ground-Penetrating Radar (GPR). Theoretically, the 1D time convolution between reflectivity and GPR signal at any infiltration time step is related to the peak of the reflected amplitude recorded in the corresponding trace in the Radargram. We used this relation ship to invert the saturated hydraulic conductivity for constant and falling head infiltrations. We present our method on synthetic examples and on two experiments carried out on sand soil. We further discuss on the uncertainties on the retrieved saturated hydraulic conductivity computed by our algorithm from the van Genuchten parameters.
Lorenzo Bruzzone - One of the best experts on this subject based on the ideXlab platform.
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Assessing the Detection Performance on Icy Targets Acquired by an Orbiting Radar Sounder
IGARSS 2019 - 2019 IEEE International Geoscience and Remote Sensing Symposium, 2019Co-Authors: Elena Donini, Francesca Bovolo, Sanchari Thakur, Lorenzo BruzzoneAbstract:Radar sounders (RS) can be used to acquire data on ice sheets and provide direct evidence of the structures in the subsurface. Many acquisitions are available from airborne RS in the Antarctica and Greenland. However, airborne data are costly, have limited spatial coverage, and nonhomogeneous characteristics. To overcome these limitations, a potential satellite-mounted RS could provide uniform coverage and consistent data quality at the cost of lower resolution and higher path loss. In this paper, we assess the performance of a possible Earth-orbiting RS by simulating and analyzing its Radargrams. The simulation approach reprocesses existing airborne RS to match the orbital RS characteristics. The simulated Radargrams are analyzed to estimate the losses and understand the detection performance of icy targets using state-of-the-art data analysis techniques. The preliminary analysis of the simulated Radargrams indicates that, under the simplified assumptions, an orbiting RS will be capable of imaging the investigated subsurface targets.
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a coherent multilayer simulator of Radargrams acquired by radar sounder instruments
IEEE Transactions on Geoscience and Remote Sensing, 2018Co-Authors: Christopher Gerekos, Leonardo Carrer, Alessandro Tamponi, Davide Castelletti, Massimo Santoni, Lorenzo BruzzoneAbstract:Reliable electromagnetic simulators are of prime importance for the design of radar sounder instruments and for supporting the subsequent analysis of their data. In this paper, we present a coherent, facet method-based simulator that can compute radar echoes from the subsurface of a target area with an arbitrary number of geological layers, thus going beyond the surface-only or the two-layer descriptions so far implemented in coherent ray-tracing radar sounder simulators. Propagation of fields throughout the subsurface is computed according to Snell’s law following a ray-tracing approach. For each ray interacting with the surface, be it a direct reflection or a refracted ray coming from the subsurface, the phase contribution of each facet is calculated through the linear phase approximation, while the total field received at the antenna is computed using Huygen’s principle. Validation simulations have been performed against the radar data of lunar and martian areas characterized by a multilayer nature and collected by the Lunar Radar Sounder instrument of JAXA’s Kaguya lunar probe and the Shallow Radar instrument onboard NASA’s Mars Reconnaissance Orbiter, respectively. Results confirm the effectiveness of the proposed simulator.
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an approach to lava tube detection in radar sounder data of the moon
International Geoscience and Remote Sensing Symposium, 2018Co-Authors: Elena Donini, Francesca Bovolo, Christopher Gerekos, Leonardo Carrer, Lorenzo BruzzoneAbstract:Lunar lava tubes are buried channels that contained thermally insulated lava during the volcanic period of the Moon. Nowadays, they are believed to be empty and thus, identified as potential habitats for humans. In recent years, numerous studies investigated the possible locations of these tubes by taking into account the distribution of gravity anomalies and the volcanic features of the surface. In this paper, we model lava tubes according to their electromagnetic behavior, and we propose a novel approach to locate lava tubes and estimate their physical properties. The method analyzes the subsurface reflections stored in Radargrams to extract the desired features automatically. Then, these features and their relationships are processed by a fuzzy rule-based system to detect the presence or absence of lava tubes. The strategy was implemented and successfully tested on simulated Radargrams with various surface properties and tunnel dimensions.
