Canterbury Plains 2.42

The Canterbury Plains are an area in New Zealand centred to the south of the city of Christchurch in the Canterbury region. Their northern extremes are at the foot of the Hundalee Hills in the Hurunui District, and in the south they merge into the plains of North Otago beyond the Waitaki River.GeographyThe Canterbury Plains were formed from quaternary moraine gravels deposited during glacial periods in the late pleistocene approximately 3 million years to 10,000 years ago. The alluvial gravels were then reworked as shingle fans of several of the larger rivers, notably the Waimakariri, the Rakaia, the Selwyn, and the Rangitata. Part of the Canterbury-Otago tussock grasslands the land is suitable for moderately intensive livestock farming, but is prone to droughts, especially when the prevailing wind is from the northwest. At these times, the weather phenomenon known as the Nor'west arch can be seen across much of the plain.A major earthquake on 4 September 2010 revealed a previously unknown geological fault beneath the Canterbury Plains and created a surface rift that offset features by as much as four meters in places.