Correction to “Ground-penetrating radar sounding in mafic lava flows: Assessing attenuation and scattering losses in Mars-analog volcanic terrains”

We have used ground‐penetrating radar to profile the depth of permafrost, to groundwater beneath permafrost, and to bedrock within permafrost in alluvial sediments of interior Alaska. We used well log data to aid the interpretations and to calculate dielectric permittivities for frozen and unfrozen materials. Interfaces between unfrozen and frozen sediments above permafrost were best resolved with wavelet bandwidths centered at and above 100 MHz. The resolution also required consideration of antenna configuration, season, and surface conditions. Depths to subpermafrost groundwater were profiled where it was in continuous contact with the bottom of the permafrost, except near transitions to unfrozen zones, where the contact appeared to dip steeply. The complexity of the responses to intrapermafrost bedrock, detected at a maximum depth of 47 m, appears to distinguish these events from those of subpermafrost saturated sediments. The relative dielectric permittivity ranged between 4.4 and 8.3 for the permafrost, and between 12 and 45 for partially to fully saturated, unfrozen silts and sands. Scattering losses are evident from intrapermafrost diffractions and from the improved penetration achieved by lowering the midband radar frequency from 100 to 50 MHz.

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Ground Penetrating Radar Survey of Mishima Lava Flows in Shizuoka

10.1190/segj102011-001.79 ◽

2011 ◽

Author(s):

Yusuke Yoshida ◽

Hirotaka Saito ◽

Takafumi Kamitani ◽

Masayuki Watanabe ◽

Yasuhide Muranaka

Keyword(s):

Ground Penetrating Radar ◽

Lava Flows ◽

Ground Penetrating

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Mapping exposed and buried lava flows using synthetic aperture and ground-penetrating radar in Craters of the Moon lava field

Geophysics ◽

10.1190/1.2793298 ◽

2007 ◽

Vol 72 (6) ◽

pp. B161-B174 ◽

Cited By ~ 5

Author(s):

Shuhab D. Khan ◽

Essam Heggy ◽

Jaime Fernandez

Keyword(s):

Ground Penetrating Radar ◽

Accuracy Assessment ◽

Volcanic Field ◽

Primary Objective ◽

Lava Flows ◽

Synthetic Aperture ◽

The Moon ◽

Lava Field ◽

L Band ◽

Ground Penetrating

The Craters of the Moon (COM) lava field has a multiple eruptive history. Burial of older flows has resulted in complex subsurface stratigraphy. For the older eruptive periods, the locations of source vents and the extension of lava flows are either speculative or unknown, because they are buried under more recent pyroclastics. In this study, we used surface and subsurface backscatter characteristics of the P- and L-band polarimetric airborne synthetic aperture radar (AIRSAR) data and ground-penetrating radar (GPR) soundings to resolve different exposed and buried lava flows. Our primary objective is to define the most effective polarization and frequency for mapping, resolving, and characterizing different lava types in the volcanic field. Polarimetric analysis of AIRSAR images from COM allows a clear recognition of the aa and pahoehoe lava types as a result of the variability in their roughness. Our results suggest that the HV cross-polarized, AIRSAR L-band is capable of producing a detailed map delineating surface lava with different surface backscattering properties. An accuracy assessment utilizing the geological map of the Inferno Cone area was performed to quantify the reliability of differentiating lava types and mapping the lava flows extension below loose pyroclastics using AIRSAR data. Results shows an ability of P-band SAR to map buried structures up to 3 meters deep under loose cinder and ash deposits, resolving buried fissures, outcrops, and lava flows that were validated with ground-truth GPR surveys. The techniques used in this study provide a tool to assess volcanic hazards in remote and inaccessible places. Also it could be an aid in the study of other planets and planetary bodies in the solar system.

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REFLECTION COEFFICIENT OF AN ELECTROMAGNETIC WAVE IN CONDUCTIVE MEDIA

Moscow University Bulletin. Series 4. Geology ◽

10.33623/0579-9406-2018-1-100-106 ◽

2018 ◽

pp. 100-106

Author(s):

M. S. Sudakova ◽

M. L. Vladov ◽

M. R. Sadurtdinov

Keyword(s):

Reflection Coefficient ◽

Ground Penetrating Radar ◽

Electromagnetic Waves ◽

Water Contamination ◽

Survey Design ◽

Direct And Inverse Problems ◽

The Difference ◽

Ground Penetrating ◽

Ideal Dielectric

Within the ground penetrating radar bandwidth the medium is considered to be an ideal dielectric, which is not always true. Electromagnetic waves reflection coefficient conductivity dependence showed a significant role of the difference in conductivity in reflection strength. It was confirmed by physical modeling. Conductivity of geological media should be taken into account when solving direct and inverse problems, survey design planning, etc. Ground penetrating radar can be used to solve the problem of mapping of halocline or determine water contamination.

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Deteksi Bentuk Objek Bawah Tanah Menggunakan Pengolahan Citra B-Scan pada Ground Penetrating Radar (GPR)

TELKA - Telekomunikasi Elektronika Komputasi dan Kontrol ◽

10.15575/telka.v3i1.54 ◽

2017 ◽

Vol 3 (1) ◽

pp. 73-83

Author(s):

Rahmayati Alindra ◽

Heroe Wijanto ◽

Koredianto Usman

Keyword(s):

Signal Processing ◽

Ground Penetrating Radar ◽

Post Processing ◽

Data Survey ◽

Ground Penetrating

Ground Penetrating Radar (GPR) adalah salah satu jenis radar yang digunakan untuk menyelidiki kondisi di bawah permukaan tanah tanpa harus menggali dan merusak tanah. Sistem GPR terdiri atas pengirim (transmitter), yaitu antena yang terhubung ke generator sinyal dan bagian penerima (receiver), yaitu antena yang terhubung ke LNA dan ADC yang kemudian terhubung ke unit pengolahan data hasil survey serta display sebagai tampilan output-nya dan post processing untuk alat bantu mendapatkan informasi mengenai suatu objek. GPR bekerja dengan cara memancarkan gelombang elektromagnetik ke dalam tanah dan menerima sinyal yang dipantulkan oleh objek-objek di bawah permukaan tanah. Sinyal yang diterima kemudian diolah pada bagian signal processing dengan tujuan untuk menghasilkan gambaran kondisi di bawah permukaan tanah yang dapat dengan mudah dibaca dan diinterpretasikan oleh user. Signal processing sendiri terdiri dari beberapa tahap yaitu A-Scan yang meliputi perbaikan sinyal dan pendektesian objek satu dimensi, B-Scan untuk pemrosesan data dua dimensi dan C-Scan untuk pemrosesan data tiga dimensi. Metode yang digunakan pada pemrosesan B-Scan salah satunya adalah dengan teknik pemrosesan citra. Dengan pemrosesan citra, data survey B-scan diolah untuk didapatkan informasi mengenai objek. Pada penelitian ini, diterapkan teori gradien garis pada pemrosesan citra B-scan untuk menentukan bentuk dua dimensi dari objek bawah tanah yaitu persegi, segitiga atau lingkaran.

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