3D EM Modelling and Inversion with Open Source Resources

1https://courses.geosci.xyz/aem2018

Thanks to…

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EsbenAndersAEM

Esben Auken Anders Vest Christiansen

Introduction

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Airborne EM: Tli Kwi cho (TKC) kimerlites

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DIGHEM (Quadrature 56kHz)

Location map at TKC

VTEM (90 μs)

Frequency domain DIGHEM survey (1992)

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DIGHEM (Quadrature 56kHz)

Configuration HCP

Frequency 900Hz-56kHz

Data unit ppm

Line spacing 200 m

Line km 52 km

# of sounding 6274

Time domain VTEM survey (2003)

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VTEM (90 μs)

Configuration Colocated-loop

Off time channel 90-6340 (μs)

Data unit pV/A-m4

Line spacing 75 m

Line km 39 km

# of sounding 26342

Airborne EM surveys: FDEM and TDEM

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DIGHEM (Quadrature 56kHz) VTEM (90 μs)

Two airborne data sets: What to do?

Questions• Discover a pipe? • Find structural details? • Pipe is 3D. What are the fields and

fluxes?• Inversion: Can I use 1D? • Need 3D? Everywhere? Over sub-

region?• How to carry out a 3D inversion?

– Access to software? – Need to build something myself?

• If I need to build software, what are the challenges?

• Can I collaborate? • What is Open Source?

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Agenda for today

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