by john west | Sep 21, 2017 | school posts, Year 11, K-12
Use some of the information here to help with your internal assessment.
A useful resource for the Tarawera eruption.
The Okataina Volcanic Complex
by john west | Sep 17, 2017 | school posts, Year 12, K-13
Where does all the basalt come from?
…..mid ocean ridges ridges to begin with then it is subducted under the east coast of the North Island
- Most basalt is produced at mid ocean ridges.
- Basalt produced at mid ocean ridges is rafted away as oceanic crust is formed.
- The process of subduction produces mainly basaltic magma
- This basalt is not rafted away from the site of eruption.
- The subducting slab comprises of basalt and gabbro with a thin veneeer of seafloor sediment.
- Water and other fluids move into the overlying “mantle wedge” where they promote partial melting.
- The resulting basalt magma makes its way into the continental crust
- The basalt can end up feeding large volanos such as Mount Ruapehu.
- Broad gently sloping cones such as Auckland’s Rangitoto Island, Lyttleton and Akaroa on the Banks Peninsula.
- In the Auckland region steep sided scoria cones are also formed by the process of fire fountaining.
- Most basalt is produced at mid ocean ridges.
- Basalt produced at mid ocean ridges is rafted away as oceanic crust is formed.
- The process of subduction produces mainly basaltic magma
- This basalt is not rafted away from the site of eruption.
- The subducting slab comprises of basalt and gabbro with a thin veneeer of seafloor sediment.
- Water and other fluids move into the overlying “mantle wedge” where they promote partial melting.
- The resulting basalt magma makes its way into the continental crust
- The basalt can end up feeding large volanos such as Mount Ruapehu.
- Broad gently sloping cones such as Auckland’s Rangitoto Island, Lyttleton and Akaroa on the Banks Peninsula.
- In the Auckland region steep sided scoria cones are also formed by the process of fire fountaining.