looking at rocks with physics

What killed the dinosaurs? Where is the billion-dollar gold deposit that will make me rich!? What these questions have in common is that we need to examine the rock-record beneath the surface. Similar to non-invasive medical imaging, where an MRI is used to generate images of your brain, in geophysics, we use gravity, seismic and electromagnetics, to make images of subsurface geology.

Presented at Nerd Night Vancouver: https://vancouver.nerdnite.com/2017/02/07/nerd-nite-v-25/

Transcript

1. looking at rocks with physics
2. The Subsurface
3. The Subsurface
4. The Subsurface
5. Option 1: Dig it up?
6. Option 2: Drill it?
7. Option 3: Use geophysics!
8. Physical properties
9. Gravity
10. Magnetics
11. Direct current resistivity
12. Seismic
13. Magnetotellurics
14. Numerical Simulations: predict data Inversion: find a model physics! Tools
16. Kimberlite Pipe - Different geologic units - Specific units are diamond-bearing Physical Properties - Low density - Moderate magnetic susceptibility - High electrical conductivity Kang, Devriese, Fournier, et al., 2017 Where are the diamonds?
17. Gravity Data Looking for low density
18. Gravity Rock model? Recovered 3D Density Vertical section Data Looking for low density
19. Magnetics Data Looking for moderate magnetic susceptibility
20. Magnetics Rock model? Recovered 3D Susceptibility Vertical section Data Looking for moderate magnetic susceptibility
21. Direct Current (DC) Resistivity Looking for high conductivity currents charges potentials (voltages)
22. Direct Current (DC) Resistivity Rock model? Recovered 3D Conductivity Vertical section Data Looking for high conductivity
23. All together now Rock model? Diamond-rich kimberlite - Low density - Moderate susceptibility - High conductivity
24. Rock model? Diamond-rich kimberlite - Low density - Moderate susceptibility - High conductivity All together now
25. From geophysics to a geologic model Rock model from geophysics Geologic model
27. What killed the dinosaurs?
28. What killed the dinosaurs? and how do we know??
29. Gravity over Chicxulub impact crater
30. Gravity over Chicxulub impact crater
31. http://geosci.xyz @lindsey_jh