Artefacts & Optical Illusions in Tomography. With emphasis on the roles of slabs, backarc basins, volatiles & cratonic roots. FACE. The optical illusion of inversion. Is yellow hot or just not cold?. What is the ambient color?. HOT COLORS ARE COLD MANTLE.
Artefacts & Optical Illusions in Tomography
With emphasis on the roles of slabs, backarc basins, volatiles & cratonic roots
The optical illusion of inversion. Is yellow hot or just not cold?
What is the ambient color?
HOT COLORS ARE COLD MANTLE
Shallow anisotropy & heterogeneity can bleed into the lower mantle
One cause of vertical streaking artefacts
(there are many)
Relative vs. absolute wavespeeds
Add the reference model back in
Plumes under California, slab under Yellowstone?
In contrast to global reference models, the actual Earth has a global LVZ between 600 and 650 km. Correcting to this new reference turns the red patches above 650 into pale blue or neutral patches & blue regions into flat slab like anomalies.
The pale yellow areas become slightly positive when a background reference model with slabs at 650 km is added back in and the blue regions above 650 become bluer.
Actual anomalies are ~2.5 times larger