New Zealand lies on two tectonic plates,
the northern island rests on the Pacific plate, also known as the Pacific Ring
of Fire, and the southern island rests on the Indo-Australian plate. These two
plate boundaries are convergent plate boundaries, “where one plate dives
beneath another or two collide” (Keller and DeVecchio 48). The image shows the
Pacific plate diving under the Indo-Australian plate just below the northern
island (indicated by bold arrows pointing northwest, dividing the two plates),
where the subduction changes directions. Following the Marlborough fault system
and the Alpine fault, the Indo-Australian plate begins to sink below the
Pacific plate (indicated by bold arrows pointing south-west). These fault
systems are what links these two plates together. The Marlborough fault system
moves the northern part of the country laterally across the southern part,
while the Alpine fault not only laterally moves the plates but brings them
closer together each year; causing the Southern Alps to raise at a rate of
approximately seven millimeters per year (“Tectonic Setting of New Zealand”).
The constant activity of two converging tectonic plates makes New Zealand prone
to many natural hazards including frequent seismic activity and reoccurring
volcanic eruptions.
Works Cited
Keller, A. Edward, and Duane E. DeVecchio. Natural Hazards, Earth's Processes as Hazards, Disasters, and Catastrophes. 4th ed., Pearson Education, 2015. Print. Accessed 31 August 2018.
Lewis, Ian D. "'Australia on a Plate' - Volcanoes on Land and around
Our Edge." Geodate, vol. 27, no. 4, Aug. 2014, p. 6. https://libproxy.mpc.edu/login?url=https://search.ebscohost.com/login.aspx?direct=true&db=f6h&AN=97912553&site=eds-live&scope=site. Accessed 31 August 2018.
“Tectonic Setting of New Zealand.” University
of Otago, https://www.otago.ac.nz/geology/research/structural-geology/alpine-fault/nz-tectonics.html. Accessed 31 August 2018.
