#47

2. Metamorphic rock formed by intense brittle fracturing and crushing without cohesion loss.
5. Dimensionless ratio of rotational to inertial forces governing fluid flow in Earth's outer core.
9. High-pressure polymorph of olivine thought to cause the 410 km seismic discontinuity.
10. a Geological window through an overthrust sheet exposing underlying autochthonous rocks beneath.
12. Dense, iron-rich oxide mineral coexisting with bridgmanite throughout the lower mantle.
13. Dimensionless number measuring the ratio of convective to conductive heat transfer in mantle convection.
14. Dense, cold slab of subducted oceanic lithosphere resting near the core-mantle boundary.

1. High-pressure silica polymorph formed during meteorite impacts, featuring octahedral silicon coordination.
3. Splitting of a light into two orthogonal polarisations when passing through an anisotropic medium, such as calcite.
4. High-pressure silicate perovskite mineral that dominates Earth's lower mantle.
6. Sodium-rich clinopyroxene mineral diagnostic of eclogite-facies metamorphism.
7. A radioactive decay and isotope geochemistry method used primarily for radiometric dating and tracing the formation and evolution of Earth's crust and mantle.
8. Isolated erosional remnant of a thrust sheet completely surrounded by younger underlying rocks.
11. Irregular, finger-like flame structures formed when dense sand sinks into underlying water-saturated mud.