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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

Transform

Describing a plate boundary where neighbouring plates slide horizontally past one another. Crust is neither systematically created nor consumed along the boundary. Earthquakes are common because friction allows stress to build before fault slip.

What to look for

San Andreas Fault in California's Sierra Madre Mountains. The fault accommodates mainly horizontal motion between the Pacific and North American plates.

Related labs

Plate boundaries →
Aerial view of the San Andreas Fault cutting across dry hills in California.
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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.