Rock Types in NZ

New Zealand's Rocks

New Zealand rocks are mainly mapped in terms of their age of formation and their rock type. In addition, the older rocks that form New Zealand’s geological basement are also divided in terms of their position relative to an ancient, now inactive tectonic plate boundary that bisects South Island and North Island. This boundary formed along the edge of Gondwanaland. The rock divisions, therefore, have overlapping ages. 

• main geological rock types in New Zealand:
• *Youngest sediments.
• *Young volcanic rocks.
• *Sedimentary cover rocks.
• *Eastern greywacke basement.
• *Eastern schist basement.
• *Central volcanic sedimentary basement.
• *Western metamorphic and sedimentary basement.
• *Granite and other intrusives.