Targeted reflection-waveform inversion of experimental ground-penetrating radar data for quantification of oil spills under sea ice

Abstract

Rapid spill detection and mapping are needed with increasing levels of oil exploration and production in the Arctic. Previous work has found that ground-penetrating radar (GPR) is effective for qualitative identification of oil spills under, and encapsulated within, sea ice. Quantifying the spill distribution will aid effective spill response. To this end, we have developed a targeted GPR reflection-waveform inversion algorithm to quantify the geometry of oil spills under and within sea ice. With known electric properties of the ice and oil, we have inverted for oil thickness and variations in ice thickness. We have tested the algorithm with data collected during a controlled spill experiment using 500-MHz radar reflection data. The algorithm simultaneously recovered the thickness of a 5-cm-thick oil layer at the base of the ice to within 8% of the control value, estimated the thickness of a 1-cm-thick oil layer encapsulated within the ice to within 30% of the control value, and accurately mapped centimeter-scale variations in ice thickness.

Antarctic Landfast Sea Ice: A Review of Its Physics, Biogeochemistry and Ecology

“…Although ice‐penetrating radar is a widely used tool for measuring the thickness of glaciers and ice sheets (e.g., Gogineni et al., 1998), the brine within sea ice greatly limits the penetration depth of microwave energy compared with freshwater ice. As a result, measurement of sea ice thickness with ice‐penetrating radar has so far been limited to surface‐based observations (Bradford et al., 2016) and wide‐bandwidth sensors (Holt et al., 2009), which have yet to be implemented in an airborne or satellite platform. As a result, space‐based methods for determining sea‐ice thickness rely on observations of the upper surface, which prove problematic for fast‐ice applications.…”

The Assessment of Relative Permittivity on Diesel Vapour in the Moisture Content of Terap Red Soil by Ground Penetrating Radar

“…This was followed by the appearance of 'vapour' and 'evaporation', which led to the different relative permittivity of soil. Therefore, the EM wave could be used to obtain contamination, as highlighted by Bano et al 19 and Bradford et al, 43 as well as increasing of bulk conductivity over time due to hydrocarbon degradation processes. 44 It was proven from the clean and contaminated measurements of GPR, that variations of reduction GPR signal amplitudes were affected by migration and chemical reaction of diesel in subsurface.…”

Radius estimation of subsurface cylindrical objects from ground-penetrating-radar data using full-waveform inversion

“…Gloaguen et al (2007) developed a pseudo-full-waveform inversion of borehole GPR data using stochastic tomography, whereas Cordua et al (2012) present a general Monte Carlo fullwaveform inversion strategy that integrates a priori information described by geostatistical algorithms with Bayesian inverse problem theory. Babcock and Bradford (2015) implemented the GPR waveform inversion for quantifying properties for nonaqueous phase liquid thin and ultrathin layers, and Bradford et al (2016) used a targeted GPR reflection-waveform inversion algorithm to quantify the geometry of oil spills under and within sea ice. Sassen and Everett (2009) combined the full-waveform inversion and the fully polarimetric GPR coherency technology to characterize the fractured rock, and Schmid et al (2016) studied the application of FWI to deduce the snow stratigraphy from the upward-looking GPR data.…”