lower mantle

The portion of the mantle below a depth of about 600 miles (1000 kilometers). Also known as inner mantle; mesosphere; pallasite shell.

Related terms:

• upper mantle
• Mantle
• plasma mantle
• core-and-mantle structure
• inner mantle
• outer mantle
• transition zone
• Mantle Plume
• D layer
• Lithosphere