What are the differences between lithosphere and asthenosphere?

The lithosphere and asthenosphere represent distinct mechanical layers in Earth's inner structure, separated by a boundary known as the LAB. The lithosphere is the cooler, rigid outer shell comprising the crust and upper mantle, while the asthenosphere is the warmer, ductile layer underneath it. Tectonic plates are composed of this rigid lithosphere and float directly across the creeping asthenosphere.

What we know

• The lithosphere-asthenosphere boundary marks a mechanical difference between layers in Earth's inner structure. [1, 2]
• The lithosphere is cooler and rigid, forming the outer shell of the planet, whereas the asthenosphere is warmer and ductile. [2, 3, 4]
• Tectonic plates are composed of the rigid lithosphere, which floats across the ductile asthenosphere beneath. [4]

Still open

• The actual depth of the lithosphere-asthenosphere boundary remains a topic of ongoing debate and study, varying by environment.

Where to go next

• how it workedHow do tectonic plates move across the Earth?
• what caused itWhat happens when tectonic plates collide?
• compared withHow is Earth's inner structure divided chemically versus mechanically?
• a case in pointWhat is mantle delamination in geology?
• the bigger pictureWhat is Irina Artemieva's research on the lithosphere?
• an unexpected connectionHow does Jupiter's moon Europa relate to Earth's lithosphere?Although Earth is the only planet known to currently have active plate tectonics, Jupiter's moon Europa shows signs of moving ice crustal plates similar to Earth's lithospheric shell.

Sources

• [1]Lithosphere-Asthenosphere boundary (Wikidata Q23581588) · CC0 1.0
• [2]Lithosphere–asthenosphere boundary · CC BY-SA 4.0
• [3]Subduction · CC BY-SA 4.0
• [4]Plate tectonics · CC BY-SA 4.0
• [5]Delamination (geology) · CC BY-SA 4.0

Your path

1. What was the history and legacy of Roman law?
2. /How do cognitive biases drive belief in pseudoscience?
3. /How does fluid mechanics apply to galaxy dynamics?
4. /What are the differences between lithosphere and asthenosphere?