Short Course Title:
Airborne Electromagnetic Data Processing and Inversion
Professor Esben Auken, Associate Professor Anders V. Christiansen and more, HydroGeophysics Group, Aarhus University
Day One: 9 June 2019 from 9:00 AM until 4:00 PM
Day Two: (Optional) 10 June 2019 from 9:00 AM until 4:00 PM
Description: The purpose of the course is to provide the participants with an insight into the ideas and theories behind processing and inversion of AEM data. The focus is on high resolution datasets collected for geological (mineral exploration), hydrological, and geotechnical purposes.
Day One Content:
The purpose of the first day of the course is to provide the participants with a theoretical insight into processing and inversion of AEM data and on how the instruments in principal works. We focus on time domain data (TAEM) but does also touch upon frequency domain data (FAEM).
The first day will have presentations focused on:
- Basic theory of (airborne) electromagnetics
- Walkthrough different airborne electromagnetic systems carried on aircraft and helicopter platforms
- Basic function of an AEM instrument
- Data processing and filtering
- System response characterization and influence on the model output
- Data calibration at test sites and with groundbased systems
- Characterization of data influenced by induced polarization
- Data inversion with special focus on Lateral and Spatial constrained inversion (time and frequency domain data)
- Smooth and sharp model description
- Hybrid inversion, inversion optimization and construction of starting models
- Inversion of data influenced by induced polarization
Day Two (optional) Content:
The purpose of the second day of the course is to provide the participants insight into how processing and inversion of AEM data is carried out in practice. For this, we use the software package Aarhus Workbench. The course is a good opportunity for new users to get to know this software, and it is an opportunity for experienced users to go deeper into the gritty nitty.
The day is optional. The course consist of a mixture of hands-on exercises and short introductions. Course participants will work with recently collected airborne datasets. All exercises and presentations are linked to the theory presented in the first day. During the hands-on exercises l cover the following topics:
Registration: Short course registration will open soon.
- Introduction to Aarhus Workbench
- Data processing – setup of data filters, culling of coupled data, workflow, and checklists
- Data inversion – Laterally Constrained and Spatial Constrained inversion, feedback to processing, smooth and sharp regularization, explicit or implicit system description, 1D and 2D (HEM only), induced polarization
- Model evaluation – residuals and misfit, maps, cross sections, reporting.