Zakázanka
Menu- Welcome to Zakázanka
- 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
A fault separating two geological periods
Walking through this area, you cross the antediluvian border between the Proterozoic and the Paleozoic. Straight through this exact spot runs the fault along which, around 350 million years ago, the first Paleozoic (Ordovician) layers fastened themselves onto Proterozoic bedrock. This occurred during the Variscan Orogeny.
The next stretch of the path consists of Paleozoic layers (from the Ordovician Period), of which only the lowermost 13 to 14 meters have survived. These are formed by basal conglomerates and volcanic tuffs. Of great interest is a seam of iron ore, which we will return to later.
The Ordovician layers are tilted parallel to the slope and form a slight synclinal bend. These deformations were wrought by Variscan mountain-building.