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Geolens

Glossary

417 words used in the labs.

Find a term from the labs, understand the process behind it, and see how it appears in the landscape. Each entry connects an explanation with a real observation and a model you can explore.

Term

Lithosphere

Earth’s rigid outer mechanical layer, comprising the crust and the uppermost mantle. It is divided into tectonic plates and overlies the weaker asthenosphere. The lithosphere is therefore thicker than the crust alone.

What to look for

Mantle peridotite carried to the surface as a xenolith within volcanic rock. It provides a sample of solid upper mantle. The lithosphere includes crust and rigid upper mantle; the green xenolith is not a piece of crust.

Related labs

Earth’s interior →Continental drift →Isostasy →
Green crystalline mantle peridotite enclosed by darker volcanic host rock at Peridot Mesa, Arizona.
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Explore further with USGS water glossary · USGS volcano glossary · NPS glacial geology · NASA Earth facts. Photograph acknowledgements are collected on the Image credits page.