1. Adaptive sampling of AEM transients
- Author
-
Domenico Di Massa, Giovanni Florio, Andrea Viezzoli, DI MASSA D., FLORIO G., VIEZZOLI A., DI MASSA, Domenico, Florio, Giovanni, and Viezzoli, Andrea
- Subjects
Engineering ,Adaptive sampling ,Computer science ,Acoustics ,0208 environmental biotechnology ,Hardware_PERFORMANCEANDRELIABILITY ,02 engineering and technology ,010502 geochemistry & geophysics ,01 natural sciences ,Signal ,Background noise ,Wavelet ,Sensitivity ,Electronic engineering ,Time domain ,Sensitivity (control systems) ,0105 earth and related environmental sciences ,business.industry ,Adaptive-gating ,Time domain electromagnetic ,Sampling (statistics) ,020801 environmental engineering ,Geophysics ,Amplitude ,Airborne electromagnetic ,Time domain electromagnetics ,Transient (oscillation) ,Transient sampling ,business ,Algorithm - Abstract
This paper focuses on the sampling of the electromagnetic transient as acquired by airborne time-domain electromagnetic (TDEM) systems. Typically, the sampling of the electromagnetic transient is done using a fixed number of gates whose width grows logarithmically (log-gating). The log-gating has two main benefits: improving the signal to noise (S/N) ratio at late times, when the electromagnetic signal has amplitudes equal or lower than the natural background noise, and ensuring a good resolution at the early times. However, as a result of fixed time gates, the conventional log-gating does not consider any geological variations in the surveyed area, nor the possibly varying characteristics of the measured signal. We show, using synthetic models, how a different, flexible sampling scheme can increase the resolution of resistivity models. We propose a new sampling method, which adapts the gating on the base of the slope variations in the electromagnetic (EM) transient. The use of such an alternative sampling scheme aims to get more accurate inverse models by extracting the geoelectrical information from the measured data in an optimal way.
- Published
- 2015