Friday Headlines, September 27, 2019
THE LATEST IN THE GEOSCIENCES
This week in geology
- Puerto Rico can’t win
This week in the environment
- Where Machu Piccu is is the fault of the faults
In recent years, Puerto Rico has been in the news most often because of hurricane damage. But Puerto Rico is also in a region of active tectonism, and is frequently rocked by earthquakes.
Puerto Rico lies along the northern margin of the Caribbean Plate, where this plate overrides the North America Plate which forms the floor of the Atlantic Ocean. As the North America Plate slides under the Caribbean Plate, it sometimes sticks briefly, then releases abruptly, causing earthquakes.
Machu Picchu, and other Incan temples were built where major faults caused bedrock to fracture into smaller blocks. The Incan peoples took advantage of these pre-broken building blocks to facilitate building their mountain temples.