The Boulder Bank (

Māori Māori or Maori can refer to: Relating to the Māori people * Māori people of New Zealand, or members of that group * Māori language, the language of the Māori people of New Zealand * Māori culture * Cook Islanders, the Māori people of the C ...

: ''Te Taero a Keropa'' or ''Te Tāhuna o Tama-i-ea'') is a very unusual naturally formed landform in Nelson, New Zealand. It is a 13 kilometre long stretch of

rocky ''Rocky'' is a 1976 American sports drama film directed by John G. Avildsen and written by and starring Sylvester Stallone. It is the first installment in the ''Rocky'' franchise and stars Talia Shire, Burt Young, Carl Weathers, and Burge ...

substrate which begins at the Mackay Bluff and ends at the Cut of the Nelson Harbour.

Haulashore Island Haulashore Island is a small island in Tasman Bay / Te Tai-o-Aorere, near Nelson, New Zealand. Formed in 1901, it was at one time a part of Boulder Bank. There is a narrow channel between the island and Arrow Rock. The island has had rabbits si ...

was once a part of the Boulder Bank, but the Cut made it an island, and it is no longer connected to the Boulder Bank. The Boulder Bank separates

Tasman Bay Tasman Bay (; officially Tasman Bay / Te Tai-o-Aorere), originally known in English as Blind Bay, is a large V-shaped bay at the north end of New Zealand's South Island. Located in the centre of the island's northern coast, it stretches along ...

and the

Nelson Haven Nelson Haven is an extensive area of mudflats northeast of Nelson, New Zealand. It is separated from Tasman Bay / Te Tai-o-Aorere by the Boulder Bank and over 8 :en:kilometre, km long and up to 2 km wide. The area is regularly completely drow ...

and is managed as a scenic reserve by the

Department of Conservation An environmental ministry is a national or subnational government agency politically responsible for the environment and/or natural resources. Various other names are commonly used to identify such agencies, such as Ministry of the Environment ...

. Land access is gained along Boulder Bank Drive, signposted at the northern end of Nelson Haven on .

Geology and geography

The Boulder Bank is composed of

granodiorite Granodiorite () is a coarse-grained ( phaneritic) intrusive igneous rock similar to granite, but containing more plagioclase feldspar than orthoclase feldspar. The term banatite is sometimes used informally for various rocks ranging from gr ...

. The source of this rock is Mackay Bluff. It is still debated what process or processes have resulted in this odd structure. Longshore drift, however, is the most accepted hypothesis for creation. The main objection for longshore drift is that

does not receive enough wave action to move the large boulders in a south west direction. Studies have been conducted since 1892 to determine speed of boulder movement. Rates of the top course gravel movement have been estimated at 7.5 metres a year.

The Cut

The Cut was made to enable the Nelson port to allow the increasing demands of sea transport for the Tasman area. Construction started in 1903 and in 1905 a 61-metre wide entrance was operational. Today the Cut is 150 metres wide and

dredged Dredging is the excavation of material from a water environment. Possible reasons for dredging include improving existing water features; reshaping land and water features to alter drainage, navigability, and commercial use; constructing da ...

every six months to maintain a depth of 10 metres.

Lighthouse

The Boulder Bank Lighthouse was erected in 1862. It is located near the port end of the Boulder Bank and was New Zealand's second permanent lighthouse. It is registered with the Historic Places Trust as a category I structure with registration number 41.

Notes

References

* Hartstein, ND and Warren Dickinson, W (2005
Wave energy and clast transport in eastern Tasman Bay, New Zealand
''

Earth Surface Processes and Landforms ''Earth Surface Processes and Landforms'' is a peer-reviewed scientific journal published by John Wiley & Sons on behalf of the British Society for Geomorphology. It covers geomorphology and more in general all aspects of Earth sciences dealing w ...

'', 31:6 (703–714). * Warren, Karen. ''Rolling Stones: Nelson's Boulder Bank, Its Place in Our History and Hearts'', 320 pp, 2009, Nikau Press, Nelson, New Zealand.

External links

The story of the Boulder Bank

The Nelson Boulder Bank
{{coord, -41.2344, 173.2964, format=dms, region:NZ_type:landmark_dim:5000, display=title Spits of New Zealand Geography of Nelson, New Zealand Barrier islands Landforms of the Nelson Region Rock formations of New Zealand