Cataclasite
“Shattered by seismic force”
Cataclasite is a fault rock formed when tectonic forces crush and grind existing rock into angular fragments without melting. Unlike mylonite which deforms plastically at depth, cataclasite forms in the shallower, more brittle upper crust during earthquakes and fault movements.
variable: angular fragments of parent rock, quartz, feldspar, fine-grained matrix
San Andreas Fault (California), Alpine Fault (New Zealand), Great Glen Fault (Scotland), Nojima Fault (Japan)
Variable (depends on parent rock)
Scientists drill into fault zones to collect cataclasite samples, studying them to understand the mechanics of past earthquakes and predict future seismic behavior.
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Related Specimens
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