Mayor Island

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Mayor Island
Māori: Tūhua
Mayor Island as seen from the sea
Mayor Island as seen from the sea
Waters Bay of Plenty
Geographical location 37 ° 17 ′  S , 176 ° 15 ′  E Coordinates: 37 ° 17 ′  S , 176 ° 15 ′  E
Mayor Island (New Zealand)
Mayor Island
length 4.7 km
width 4 km
surface 12.77dep1
Highest elevation Opuahau
354  m

Mayor Island ( Māori Tūhua ) is an island of volcanic origin in the northwestern part of the Bay of Plenty off the North Island of New Zealand .

Origin of name

The island has a special meaning for the Māori , as obsidian occurs here. This volcanic glass was valued as a material for cutting tools. In the Māori language , obsidian is called " Tūhua " and so they transferred the name to the island. The British navigator and explorer Captain James Cook named the island " Mayor Island " when he sighted it on November 3, 1769 on his voyage of discovery. The name was given in honor of Lord Mayor's Day , which was to take place in London a few days later .

geography

The almost 13 km² island, 4.7 km long and 4 km wide, is located around 42 km north of the city center of Tauranga and around 28 km east-northeast of Waihi Beach . The highest point, the Opuahau , is part of the southern edge of the caldera and measures 354  m high .

geology

Mayor Island consists of a shield volcano with two overlapping calderas . The volcano is said to have formed 130,000 years ago and in the past to have become active at least every 3000 years. Its eruptions are divided into three cycles based on geological data. In the first cycle, which lasted until 36,000 years ago, the volcano was formed by twelve explosive eruptions and at least nine lava flows , which can still be seen today on the western and northeastern caldera rim. The end of this cycle marked the collapse of the volcanic core and the formation of the first caldera.

The second cycle took place from 33,000 years ago to 8,000 years ago. Two volcanic cores formed in it outside the caldera in the northwest of the volcano. The ashes of the eruptions reached parts of the North Island and the cycle also ended with the formation of the second caldera.

The third cycle began 6340 years ago and continues to this day, according to geologists' definitions. A group of volcanic cores formed in it, from which lava flows into the existing caldera. The age of the lava is difficult to determine. The overwhelming number of lies assume, however, that the lava flows are more recent and formed between 500 and 1000 years ago and that the volcano is in the early stages of its third cycle.

There are numerous thermal springs and two small crater lakes on the island. The Lake Aroarotamahine , which has a green color and the Lake Te Paritu that is almost black, located on the eastern edge within the caldera. The water of the lakes and the abundance of groundwater on the island suggest that future eruptions of the volcano will be accompanied by phreatomagmatic explosions .

Protected area

The island has been designated a wildlife sanctuary since 1953 and is administered by the Tūhua Trust Board . Be protected so that, among other things occurring on the island of Maori Glockenhonigfresser , TUI , Maori fruit pigeons , New Zealand Kuckuckskäuze , fantail , Kakas , Gray Warbler , gray coat glasses birds , kingfishers and the New Zealand stilt Pied -called stilt .

Marine reserve

Three nautical miles around the island, the Tūhua ( Mayor Island ) Marine Reserve was designated a marine reserve that forbids fishing on the coastal strip of the north side of the islands and only allows fishing in the rest of the reserve under strict conditions. Nets and long lines are also forbidden there, and you are only allowed to go ashore in Opo Bay ( South East Bay ) if someone from the Department of Conservation is present to accompany you.

history

The volcanic island was formerly inhabited by Māori , who belonged to the clan of Te Whānau A Tauwhao ki Tūhua . At the end of the 19th century, the island was uninhabited as its former residents moved to Kati-Kati and Matakana Island . The island is now privately owned and administered by the Tūhua Trust Board .

literature

  • BF Houghton, CJN Wilson, SD Weaver, MA Lanphere, J. Barclay : Volcanic hazards at Mayor Island . In: Ministry of Civil Defense (ed.): Volcanic hazards information series 6 . 1995 (English, online [accessed December 12, 2018]).
  • EL Adams : Tuhua - Mayor Island . In: Historical Section Waihi Arts Center, Museum Association Inc. , Paeroa & District Historical Society District History Museum (Eds.): Ohinemuri Regional History Journal . Volume 11 , May 1969 (English, online [accessed December 12, 2018]).

Web links

Individual evidence

  1. ↑ a b c d e f g Tuhua ( Mayor Island ). Department of Conservation , accessed December 11, 2018 .
  2. ↑ a b Adams : Tuhua - Mayor Island . In: Ohinemuri Regional History Journal . 1969.
  3. ↑ Coordinates and longitudes were determined using Goggle Earth Pro Version 7.3.1.4507 on November 12, 2018
  4. ^ A b c d Houghton, Wilson, Weaver, Lanphere, Barclay : Volcanic hazards at Mayor Island . 1995, p.  23 .
  5. ^ Map & boundaries . Department of Conservation , accessed December 12, 2018 .