How the Canterbury region was formed

What are we learning today?

You need to be able to:

Explain how the following were formed:

a) Southern Alps

b) Banks Peninsula

c) Canterbury Plains

NZ is on the Pacific “Ring of Fire” - an area of earthquakes and volcanoes on the edge of the

Pacific Plate around the Pacific Ocean.

NZ sits on the boundary between two major tectonic plates.

Indo-Australian Plate

Pacific Plate

How fast do the plates move?

What did New Zealand look like 25

million years ago?

Most of NZ was still covered by water

Southern Alps uplift25-15 Million Years Ago...

Plates begin to collide and the Alpine Fault beginning to form

Christchurch

New areas of land are pushed above sea level

Southern Alps uplift15-5 Million Years Ago...

The Southern Alps start to form

Christchurch

Nearly 20km uplift of land has occurred along the Alpine Fault

Southern Alps uplift5 Million Years Ago - Today...

Christchurch

Thank goodness for erosion !!!

If no erosion of the mountains had taken place, the Southern Alps would be 20km higher than they are

today!!

Predicted height of Southern Alps with no erosion occurring

Current height of Southern Alps (3.75km)

Lake Pukaki

Mount Cook

Exercise 1: On the map, add the following labels:

Banks Peninsula Akaroa Harbour Lyttleton HarbourCanterbury Plains Southern Alps Waimakaririri RiverRakaia River

Southern Alps upliftHow was the Canterbury Region formed?

Exercise 2: Use the key words and dates below to complete the following sentences: 1. The Southern Alps were formed by...  2. Banks Peninsula was formed by... 3. The Canterbury Plains were formed by... 

Keywords: glacierserosionalluvial soilriversshield volcanoalpine fault

Dates: 15 million years ago25 million years ago3 million years ago

Exercise 2: Answers 

1. The Southern Alps were formed by the Alpine Fault pushing up,

25 million years ago

2. Banks Peninsula was formed by a shield volcano, 15 million years ago

3. The Canterbury Plains were formed by glaciers, erosion and rivers washing alluvial soil down from the mountains, 3 million years ago