Massive Diamond Cache – Earth՚s Interior YouTube Lecture Handouts
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Massive Diamond Cache - Earth՚s Interior
- More than a quadrillion (1016) tons of diamond b/w 90 - 150 miles (145 to 240 km)
More than 100 miles below earth՚s surface – no drilling
- Within cratonic roots (deepest) — the oldest and most immovable sections of rock that lie beneath the center of most continental tectonic plates
- Cratonic roots are shaped like inverted mountains that stretch through the Earth՚s crust and into the mantle.
- Craton - polydeformed and metamorphosed crystalline and metamorphic rocks
- No more exotic but a common mineral
- Research by Ulrich Faul, a research scientist in MIT
- Anomaly in seismic data – construct image of Earth՚s interior
- Sound waves move at various speeds through the Earth, depending on the temperature, density, and composition of the rocks through which they travel.
- Spikes in seismic speed was seen
- The sound velocity in diamond is more than twice as fast as in the dominant mineral in upper mantle rocks, olivine.
- Olivine - mafic and ultramafic igneous rocks and as a primary mineral in certain metamorphic rocks (common in subsurface but weathers quickly on surface)
- Craton which is naturally less dense than the surrounding mantle.
- Diamonds are forged in the high-pressure, high-temperature environment of the deep Earth and only make it close to the surface through volcanic eruptions that occur every few tens of millions of years.
- Eruptions carve out geologic “pipes” made of rock type kimberlite (named after Kimberley, South Africa, where the first diamonds in this type of rock were found)
- Kimberlite pipes seen in Canada, Siberia, Australia, and South Africa
✍ Manishika