Zakázanka
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- In search of bygone eons
- An example of a reverse fault and a crush zone
- Folds
- A fault separating two geological periods
- Iron ore
- Exposed boundary
- What is growing here (1)
- What is growing here (2)
- Little warm lovers
- Sun lovers
- Bedrock
- Fluvial sandy gravels of the vineyard terrace
- Local denizens of the air
- A window into Prague's geological past
- Iron ore on the zoo grounds
- The rock face bears silent witness
- Regeneration of the rocky steppe
An example of a reverse fault and a crush zone
Here, we can see an interesting phenomenon known as a reverse fault. The Proterozoic rocks found on Prague Zoo grounds are riven in many places by faults and folds that appeared during mountain-building events. A reverse fault is one of these typical faults.
Both of these phenomena, a reverse fault and a crush zone, are illustrated by this exposure. The crush zone abounds with irregular white quartz filaments and lenses that formed through the crystallization of silicon dioxide (SiO2) out of the solutions that permeate the crush zone.
Fault
A reverse fault is one in which a fault block slides up the inclined plane formed by another fault block, pushing the latter downward. The directed stresses associated with the genesis of reverse faults sometimes result in rock being crushed in the vicinity of the fault zone, particularly under the fault.
