rockpassion
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- #21
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it is a river not a sea, and they are river cribs made of basalt blocks. my stone is more feldspathic in nature not basaltic.The origin?
Search for: spiegelwaal Nijmegen
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Spiegelwaal Nijmegen
www.interregnorthsea.eu
Probable origin?
https://www.spiegelwaalnijmegen.nl/ look at the rock sea wall.
- Geowizard
Similar construction as sea wall. Similar rocks too!it is a river not a sea, and they are river cribs made of basalt blocks. my stone is more feldspathic in nature not basaltic.


oke that is very cool thanks for the researchSOLVED:
Bingo!
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Basalt near the...
Spiegelwaal in Nijmegen, Netherlands, refers to the construction material used for bank protection, specifically in the form of rock groynes, barriers, and reinforcement blocks. These basalt blocks, along with asphalt, form a barrier between the river Waal and its new secondary channel, the Spiegelwaal.
Key Details on Basalt at Spiegelwaal:
Function: The basalt blocks are used for reinforcing the river bottom and banks, particularly to prevent erosion.
Location: They are present along the banks, in river groynes, and in the barriers separating the main river from the Spiegelwaal channel.
Visibility: These structures are often visible, especially during periods of low water levels, such as in summer.
These volcanic rocks are imported for hydraulic engineering projects in the Netherlands, including the stabilization of the Waal riverbed near the Nijmegen Waalkade.
Fun Stuff! 🤓
- Geowizard