Project

Back to overview

True amplitude recovery of multifold multicomponent georadar data

English title True amplitude recovery of multifold multicomponent georadar data
Applicant Green Alan G.
Number 129615
Funding scheme Project funding
Research institution Institut für Geophysik ETH Zürich
Institution of higher education ETH Zurich - ETHZ
Main discipline Geophysics
Start/End 01.04.2010 - 31.03.2011
Approved amount 52'603.00
Show all

Keywords (8)

georadar; hydrogeophysics; relative-permittivity; electrical-conductivity; full-waveform-inversion; algorithm development; ground-penetrating radar; GPR

Lay Summary (English)

Lead
Lay summary
The complexity of full-waveform inversion of ground-penetrating radar data (GPR) lies in the high degree of non-linearity of the problem, which can cause difficulties (e.g., convergence behaviour, erroneous reconstructions) with existing time-domain schemes unless the starting model is very close to the true situation. We have developed a new algorithm specifically designed to tame the non-linearity issue that afflicts inverse scattering problems, particularly in high contrast media. We first investigate the limitations of current full-waveform time-domain inversion schemes for GPR data and then introduce a much-improved approach based on a combined frequency-time-domain analysis. we then show by means of several synthetic tests and theoretical considerations that local minima trapping (common in full bandwidth time-domain inversion) can be avoided by starting the inversion with only the low frequency content of the data. Resolution associated with the high frequencies can then be achieved by progressively expanding to wider bandwidths as the iterations proceed. Although based on a frequency analysis of the data, the new method is entirely implemented by means of a time-domain forward solver, thus combining the benefits of the frequency-domain (low-frequency inversion conveys stability and avoids convergence to a local minimum, whereas high-frequency inversion conveys resolution) and time-domain methods (simplicity of interpretation and recognition of events and ready availability of simulation tools).
Direct link to Lay Summary Last update: 21.02.2013

Responsible applicant and co-applicants

Employees

Associated projects

Number Title Start Funding scheme
113669 True amplitude recovery of multifold multicomponent georadar data 01.01.2007 Project funding
113669 True amplitude recovery of multifold multicomponent georadar data 01.01.2007 Project funding

Abstract

We are developing a fast algorithm for the full-waveform tomographic inversion of vector ground-penetrating radar data that should eventually be applicable to surface, crosshole and surface-to-borehole data sets, either individually or jointly. Although full-waveform approaches require far more computer resources than conventional ray-based methods, they offer the potential of providing much higher resolution structural information and key details on the physical properties of the target structures.
-