Harold Wellman

Last updated
Harold Wellman
Born
Harold William Wellman

(1909-03-25)25 March 1909
Devonport, England
Died28 April 1999(1999-04-28) (aged 90)
NationalityNew Zealand
OccupationGeologist
Known forDiscovery of the Alpine Fault
Spouse(s)Joan Evelyn Butler

Harold William Wellman (25 March 1909 – 28 April 1999) was an English-born New Zealand geologist known for his work on plate tectonics. He is notable for his discovery of South Island's Alpine Fault. [1] Wellman became a Fellow of the Royal Society of New Zealand in 1954, and was awarded the Hector Memorial Medal and Prize in 1957 and the McKay Hammer Award in 1959.

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Life and career

Elevation map of the west coast of New Zealand's South Island showing the sharp line formed by the Alpine Fault. North is to the right. Alpine Fault SRTM.jpg
Elevation map of the west coast of New Zealand's South Island showing the sharp line formed by the Alpine Fault. North is to the right.

Harold Wellman was born in Devonport, England, to Evan Edward Wellman, an engineer in the Royal Navy, and May Kinglake Hoare. In 1927 his father was deployed at Devonport, Auckland, New Zealand for three years and the family moved to New Zealand. Harold Wellman first worked as a surveyor, but was soon forced to become a gold prospector on the West Coast due to the lack of work available during the depression. [2]

In the mid-1930s Wellman began his geological study while working in mineral exploration for the Department of Scientific and Industrial Research. He initially studied at Canterbury University, later moving to Victoria University where he completed his Bachelor of Science (1939) and Master of Science (1941). That same year he married Joan Evelyn Butler in Dunedin, with whom he had three children.

Between 1952 and 1958 he worked for the New Zealand Geological Survey based in Wellington. During this time he received major awards for his research, gaining a fellowship from the Royal Society of New Zealand in 1954, an honorary Doctor of Sciences from the University of New Zealand in 1956 and he was awarded the Royal Society's Hector Memorial Medal and Prize in 1957. He later joined the Department of Geology at Victoria University, becoming chair in 1970 and an emeritus professor in 1975.

Works and discoveries

During his career Harold Wellman published on a wide variety of geological topics, however, he was most influential in discovering the Alpine Fault and its importance to New Zealand's geology. In 1940 Harold Wellman first identified that the Southern Alps was related to a fault line which ran for approximately 650 km (400 miles). The fault was officially named the Alpine Fault in 1942. At the same time, Harold Wellman proposed the 480 km (300 miles) lateral displacement on the Alpine Fault. [3]

This displacement was inferred by Harold Wellman due in part to the similarity of rocks in Southland and Nelson on either side of the Alpine Fault. Lateral displacements of this magnitude could not be explained by pre-plate tectonics geology and his ideas were not initially widely accepted until 1956. [4] Wellman also proposed in 1964 that the Alpine Fault was a Cenozoic structure, which was in conflict with the older Mesozoic age accepted at the time. This idea coupled with the displacement on the fault proposed that the earth's surface was in relatively rapid constant movement and helped to overthrow the old geosynclinal hypothesis in favour of plate tectonics.

Related Research Articles

Southern Alps Mountain range on the South Island in New Zealand

The Southern Alps / Kā Tiritiri o te Moana is a mountain range extending along much of the length of New Zealand's South Island, reaching its greatest elevations near the range's western side. The name "Southern Alps" generally refers to the entire range, although separate names are given to many of the smaller ranges that form part of it.

1931 Hawkes Bay earthquake earthquake

The 1931 Hawke's Bay earthquake, also known as the Napier earthquake, occurred in New Zealand at 10:47 am on 3 February, killing 256, injuring thousands and devastating the Hawke's Bay region. It remains New Zealand's deadliest natural disaster. Centred 15 km north of Napier, it lasted for two and a half minutes and measured magnitude 7.8 Ms (magnitude 7.9 Mw). There were 525 aftershocks recorded in the following two weeks, with 597 being recorded by the end of February. The main shock could be felt in much of New Zealand, with reliable reports coming in from as far south as Timaru, on the east coast of the South Island.

Transform fault Plate boundary where the motion is predominantly horizontal

A transform fault or transform boundary is a fault along a plate boundary where the motion is predominantly horizontal. It ends abruptly where it connects to another plate boundary, either another transform, a spreading ridge, or a subduction zone.

Alpine Fault A right-lateral strike-slip fault, that runs almost the entire length of New Zealands South Island.

The Alpine Fault is a geological fault that runs almost the entire length of New Zealand's South Island and forms the boundary between the Pacific Plate and the Indo-Australian Plate. The Southern Alps have been uplifted on the fault over the last 12 million years in a series of earthquakes. However, most of the motion on the fault is strike-slip, with the Tasman district and West Coast moving North and Canterbury and Otago moving South. The average slip rates in the fault's central region are about 38mm a year, very fast by global standards. The last major earthquake on the Alpine Fault was in c.1717 AD, the probability of another one occurring within the next 50 years is estimated at about 30 percent.

Hope Fault Fault in New Zealand

The Hope Fault is an active dextral strike-slip fault in the northeastern part of South Island, New Zealand. It forms part of the Marlborough Fault System, which accommodates the transfer of displacement along the oblique convergent boundary between the Indo-Australian Plate and Pacific Plate, from the transform Alpine Fault to the Hikurangi Trench subduction zone.

1888 North Canterbury earthquake

The 1888 North Canterbury earthquake occurred at 4:10 am on 1 September following a sequence of foreshocks that started the previous evening, and whose epicentre was in the North Canterbury region of the South Island of New Zealand. The epicentre was approximately 35 kilometres (22 mi) west of Hanmer.

1855 Wairarapa earthquake

The 1855 Wairarapa earthquake occurred on 23 January at about 9 p.m., affecting much of the Cook Strait area of New Zealand, including Marlborough in the South Island and Wellington and Wairarapa in the North Island. In Wellington, close to the epicenter, shaking lasted for at least 50 seconds. The moment magnitude is estimated to have been in the range 8.2–8.3, the most powerful recorded in New Zealand since systematic European colonisation began in 1840. This earthquake was associated with the largest observed movement on a strike-slip fault, maximum 18 metres (59 ft). It has been suggested that the surface rupture formed by this event helped influence Charles Lyell to link earthquakes with rapid movement on faults.

Geology of New Zealand

The geology of New Zealand is noted for its volcanic activity, earthquakes and geothermal areas because of its position on the boundary of the Australian Plate and Pacific Plates. New Zealand is part of Zealandia, a microcontinent nearly half the size of Australia that broke away from the Gondwanan supercontinent about 83 million years ago. New Zealand's early separation from other landmasses and subsequent evolution have created a unique fossil record and modern ecology.

1848 Marlborough earthquake

The 1848 Marlborough earthquake was a 7.5 earthquake that occurred at 1:40 a.m. on 16 October 1848 and whose epicenter was in the Marlborough region of the South Island of New Zealand.

1843 Wanganui earthquake

The 1843 Wanganui earthquake occurred on 8 July at 16:45 local time with an estimated magnitude of 7.5 on the Mw scale. The maximum perceived intensity was IX (Violent) on the Mercalli intensity scale' possibly reaching X (Extreme). The epicentre is estimated to have been within a zone extending 50 km northeast from Wanganui towards Taihape. GNS Science has this earthquake catalogued and places the epicenter 35 km east of Taihape, near the border of Hawke's Bay. This was the first earthquake in New Zealand over magnitude 7 for which written records exist, and the first for which deaths were recorded.

1929 Arthurs Pass earthquake earthquake

The 1929 Arthur's Pass earthquake occurred at 10:50 pm NZMT on 9 March. The sparsely settled region of the Southern Alps shook for four minutes. Tremors continued almost continuously until midnight and sporadic strong aftershocks were felt for several days.

Geology of Canterbury, New Zealand

Canterbury in New Zealand is the portion of the South Island to the east of the Southern Alps, from the Waiau River in the north, to the Waitaki River in the south.

Clarence Fault

The Clarence Fault is an active dextral strike-slip fault in the northeastern part of South Island, New Zealand. It forms part of the Marlborough Fault System, which accommodates the transfer of displacement along the oblique convergent boundary between the Indo-Australian Plate and Pacific Plate, from the transform Alpine Fault to the Hikurangi Trench subduction zone.

Wellington Fault Fault in New Zealand

The Wellington Fault is an active seismic fault in the southern part of the North Island of New Zealand. It is a dextral (right-lateral) strike-slip fault with variable amounts of vertical movement causing uplift to the northwest, as expressed by a series of ranges. It forms part of the North Island Fault System, which accommodates the transfer of displacement along the oblique convergent boundary between the Indo-Australian Plate and Pacific Plate.

2014 Eketahuna earthquake

The 2014 Eketahuna earthquake struck at 3:52 pm on 20 January, centred 15 km east of Eketahuna on the south-east of New Zealand's North Island. It had a maximum perceived intensity of VII (severe) on the Mercalli intensity scale. Originally reported as magnitude 6.6 on the Richter Scale, the earthquake was later downgraded to a magnitude of 6.2. A total of 1112 aftershocks were recorded, ranging between magnitudes 2.0 and 4.9 on the Richter Scale.

Richard Patrick Suggate was a New Zealand geologist, known for his research into coal properties and coal rank, and into the advances and retreats of New Zealand's glaciers. From 1974 to 1986 he served as director of the New Zealand Geological Survey.

Rupert Sutherland is a New Zealand geologist and academic specializing in tectonics and geophysics at the Victoria University of Wellington and a principal scientist at GNS Science. Sutherland has been described as "one of New Zealand’s leading earth science researchers" by the Royal Society of New Zealand.

George William Grindley was a New Zealand geologist. The Grindley Plateau in Antarctica is named in his honour.

Southland Syncline

The Southland Syncline is a major geological structure located in the Southland Region of New Zealand's South Island. The syncline folds the Mesozoic greywackes of the Murihiku Terrane. The northern limb of the fold is steep to overturned, while the southern limb dips shallowly to the northeast. The axial plan dips to the northeast and the axis plunges to the southeast.

References

  1. Grapes, Rodney H.; Patterson, John (December 2009). "Alexander McKay and the Awatere fault, New Zealand: Ground rupturing and large‐scale horizontal displacement". New Zealand Journal of Geology and Geophysics. 52 (4): 349–365. doi:10.1080/00288306.2009.9518463.
  2. "Harold William Te Ara Encyclopedia of New Zealand". Te Ara Encyclopedia of New Zealand.
  3. Nathan, S. (2011). "Harold Wellman and the Alpine Fault of New Zealand" (PDF). Episodes. 34 (1): 51–56.
  4. Wellman, H. w. (1956). "Structural outline of New Zealand (No. 121)". New Zealand Department of Scientific and Industrial Research, Wellington. 121 (4).

Further reading