New Zealand is an island country located in the southwestern Pacific Ocean, near the centre of the water hemisphere. It consists of a large number of islands, estimated around 700, mainly remnants of a larger land mass now beneath the sea. The land masses by size are the South Island and the North Island, separated by the Cook Strait. The third-largest is Stewart Island / Rakiura, located 30 kilometres off the tip of the South Island across Foveaux Strait. Other islands are significantly smaller in area. The three largest islands stretch 1,600 kilometres across latitudes 35° to 47° south. New Zealand is the sixth-largest island country in the world, with a land size of 268,710 km2 (103,750 sq mi).
The Southern Alps are 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.
Mayor Island / Tūhua is a dormant shield volcano located off the Bay of Plenty coast of New Zealand's North Island. It lies 35 kilometres (22 mi) north of Tauranga and covers 13 km2 (5 sq mi).
The Alpine Fault is a geological fault that runs almost the entire length of New Zealand's South Island, being about 600 km (370 mi). long, and forms the boundary between the Pacific Plate and the 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 38 mm (1.5 in) a year, very fast by global standards. The last major earthquake on the Alpine Fault was in about 1717 AD with a great earthquake magnitude of 8.1. The probability of another one occurring within the next 50 years is estimated at 75 percent.
Chikyū (ちきゅう) is a Japanese scientific drilling ship built for the Integrated Ocean Drilling Program (IODP). The vessel is designed to ultimately drill 7 km beneath the seabed, where the Earth's crust is much thinner, and into the Earth's mantle, deeper than any other hole drilled in the ocean thus far.
An enhanced geothermal system (EGS) generates geothermal electricity without natural convective hydrothermal resources. Traditionally, geothermal power systems operated only where naturally occurring heat, water, and rock permeability are sufficient to allow energy extraction. However, most geothermal energy within reach of conventional techniques is in dry and impermeable rock. EGS technologies expand the availability of geothermal resources through stimulation methods, such as 'hydraulic stimulation'.
The volcanism of New Zealand has been responsible for many of the country's geographical features, especially in the North Island and the country's outlying islands.
The 6,300-metre (20,700 ft) deep Puysegur Trench is a deep cleft in the floor of the south Tasman Sea formed by the subduction of the Indo-Australian Plate under the Pacific Plate to the south of New Zealand. Immediately to its east lies the Puysegur Ridge, a northern extension of the Macquarie Ridge, which separates the Puysegur Trench from the Solander Trough. To the west is the expanse of the Tasman Basin, which stretches most of the distance to Australia. To the north of the trench lies the Fiordland Basin, which can be considered an extension of the trench. The Puysegur Trench mirrors the Kermadec Trench and Tonga Trench north of New Zealand.
The 1855 Wairarapa earthquake occurred on 23 January at about 9.17 p.m., affecting much of the Cook Strait area of New Zealand, including Marlborough in the South Island and Wellington and the Wairarapa in the North Island. In Wellington, close to the epicentre, shaking lasted for at least 50 seconds. The moment magnitude of the earthquake has been estimated as 8.2, the most powerful recorded in New Zealand since systematic European colonisation began in 1840. This earthquake was associated with the largest directly observed movement on a strike-slip fault, maximum 18 metres (59 ft). This was later revised upward to about 20 m (66 ft) slip, with a local peak of 8 m (26 ft) vertical displacement on lidar studies. It has been suggested that the surface rupture formed by this event helped influence Charles Lyell to link earthquakes with rapid movement on faults.
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.
Lake Taupō, in the centre of New Zealand's North Island, fills the caldera of the Taupō Volcano, a large rhyolitic supervolcano. This huge volcano has produced two of the world's most powerful eruptions in geologically recent times.
The Japan Trench Fast Drilling Project (JFAST) was a rapid-response scientific expedition that drilled oceanfloor boreholes through the fault-zone of the 2011 Tohoku earthquake. JFAST gathered important data about the rupture mechanism and physical properties of the fault that caused the huge earthquake and tsunami which devastated much of northeast Japan.
Kathleen Ann Campbell is an American-born New Zealand geology and astrobiology academic. She is currently a full professor at the University of Auckland. Her work is broadly centred in the topic of paleoecology and how ancient organisms interacted with their environment and whether they were capable of surviving under extremely hard conditions. Much of her research carries wide-ranged associations with questions about the origin of life and the possibility of life on Mars. She graduated from the University of Southern California and she is currently a full professor at the University of Auckland.
Richard Hugh Sibson is a New Zealand structural geologist and emeritus professor at the University of Otago, who has received numerous honors and awards for his work in the field of earthquake research. He has caused a 'fundamental shift' in the interpretation of the relationship between earthquakes and fault zone geology and on the origin of fault-hosted mineral deposits.
Rupert Sutherland is a New Zealand geologist and academic specialising 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.
Laura Martin Wallace is a geodetic principal scientist who works between the University of Texas at Austin and GNS Science in New Zealand. She was elected Fellow of the Royal Society Te Apārangi in 2018.
The Dodd-Walls Centre for Photonic and Quantum Technologies is a New Zealand Centre of Research Excellence, established in 2015, hosted by the University of Otago, and composed of researchers in six New Zealand universities as well as partner institutions in the US, United Kingdom, and Singapore. It does fundamental research on the quantum nature of matter, the physics and optics of light, and the manipulation of individual photons. New knowledge and applications are commercialised for industries including agritech, medicine, and civil engineering.
Susan Marian Ellis is a geophysicist based in New Zealand, who specialises in modelling the geodynamics of the Earth's crust deformation, at different scales. Ellis is a principal scientist at GNS Science and her main interests are in subduction, seismology, tectonics, crust and petrology. Ellis's current work focuses on the influence of faulting on stresses in the crust, and how this is related to geological hazard and the tectonic settings in New Zealand.
The Otago fault system contains multiple faults with the potential to have rupture events greater than 7 in magnitude. These are parallel to, and to the east of the Alpine Fault in the south eastern part of the South Island of New Zealand. It accommodates about 2 mm (0.079 in)/year of contraction.
