Cataclastic Breccia
“Fault-shattered rock cemented anew”
Cataclastic breccia forms along fault zones where tectonic forces crush existing rock into angular fragments, which are then recemented by mineral-bearing fluids circulating through the fractures. These rocks are geological records of ancient earthquakes and tectonic violence.
angular fragments of host rock, quartz veins, calcite cement, iron oxides, clay gouge
San Andreas Fault zone (California, USA), Alpine Fault (New Zealand), North Anatolian Fault (Turkey), Great Glen Fault (Scotland)
Variable
Cataclastic breccias along fault zones often host gold deposits because the same fracture networks that shatter rock also provide pathways for gold-bearing hydrothermal fluids.
Test Your Knowledge
Why do gold deposits frequently occur in cataclastic breccia zones?
Related Specimens
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