Tectonic uplift in the context of "Coral island"

New Zealand is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island (Te Ika-a-Māui) and the South Island (Te Waipounamu)—and over 600 smaller islands. It is the sixth-largest island country by area and lies east of Australia across the Tasman Sea and south of the islands of New Caledonia, Fiji, and Tonga. The country's varied topography and sharp mountain peaks, including the Southern Alps (Kā Tiritiri o te Moana), owe much to tectonic uplift and volcanic eruptions. New Zealand's capital city is Wellington, and its most populous city is Auckland.

The islands of New Zealand were the last large habitable land to be settled by humans. Between about 1280 and 1350, Polynesians began to settle in the islands and subsequently developed a distinctive Māori culture. In 1642, the Dutch explorer Abel Tasman became the first European to sight and record New Zealand. In 1769 the British explorer Captain James Cook became the first European to set foot on and map New Zealand. In 1840, representatives of the United Kingdom and Māori chiefs signed the Treaty of Waitangi, which paved the way for Britain's declaration of sovereignty later that year and the establishment of the Crown Colony of New Zealand in 1841. Subsequently, a series of conflicts between the colonial government and Māori tribes resulted in the alienation and confiscation of large amounts of Māori land. New Zealand became a dominion in 1907; it gained full statutory independence in 1947, retaining the monarch as head of state. Today, the majority of New Zealand's population of around 5.3 million is of European descent; the indigenous Māori are the largest minority, followed by Asians and Pasifika. Reflecting this, New Zealand's culture mainly derives from Māori and early British settlers but has recently broadened from increased immigration. The official languages are English, Māori, and New Zealand Sign Language, with the local dialect of English being dominant.

Geologically, a volcanic island is an island of volcanic origin. The term high island can be used to distinguish such islands from low islands, which are formed from sedimentation or the uplifting of coral reefs (which have often formed on sunken volcanoes).

Denudation is the geological process in which moving water, ice, wind, and waves erode the Earth's surface, leading to a reduction in elevation and in relief of landforms and landscapes. Although the terms erosion and denudation are used interchangeably, erosion is the transport of soil and rocks from one location to another, and denudation is the sum of processes, including erosion, that result in the lowering of Earth's surface. Endogenous processes such as volcanoes, earthquakes, and tectonic uplift can expose continental crust to the exogenous processes of weathering, erosion, and mass wasting. The effects of denudation have been recorded for millennia but the mechanics behind it have been debated for the past 200 years and have only begun to be understood in the past few decades.

The Structure and Distribution of Coral Reefs, Being the first part of the geology of the voyage of the Beagle, under the command of Capt. Fitzroy, R.N. during the years 1832 to 1836, was published in 1842 as Charles Darwin's first monograph, and set out his theory of the formation of coral reefs and atolls. He conceived of the idea during the voyage of the Beagle while still in South America, before he had seen a coral island, and wrote it out as HMS Beagle crossed the Pacific Ocean, completing his draft by November 1835. At the time there was great scientific interest in the way that coral reefs formed, and Captain Robert FitzRoy's orders from the Admiralty included the investigation of an atoll as an important scientific aim of the voyage. FitzRoy chose to survey the Keeling Islands in the Indian Ocean. The results supported Darwin's theory that the various types of coral reefs and atolls could be explained by uplift and subsidence of vast areas of the Earth's crust under the oceans.

The book was the first volume of three Darwin wrote about the geology he had investigated during the voyage, and was widely recognised as a major scientific work that presented his deductions from all the available observations on this large subject. In 1853, Darwin was awarded the Royal Society's Royal Medal for the monograph and for his work on barnacles. Darwin's theory that coral reefs formed as the islands and surrounding areas of crust subsided has been supported by modern investigations, and is no longer disputed, while the cause of the subsidence and uplift of areas of crust has continued to be a subject of discussion.

The word orogeny comes from Ancient Greek ὄρος (óros) 'mountain' and γένεσις (génesis) 'creation, origin'. Although it was used before him, the American geologist G. K. Gilbert used the term in 1890 to mean the process of mountain-building, as distinguished from epeirogeny.

River incision is the narrow erosion caused by a river or stream that is far from its base level. River incision is common after tectonic uplift of the landscape. Incision by multiple rivers result in a dissected landscape, for example a dissected plateau. River incision is the natural process by which a river cuts downward into its bed, deepening the active channel. Though it is a natural process, it can be accelerated rapidly by human factors including land use changes such as timber harvest, mining, agriculture, and road and dam construction. The rate of incision is a function of basal shear-stress. Shear stress is increased by factors such as sediment in the water, which increase its density. Shear stress ${\displaystyle t}$ is proportional to water mass, gravity, and WSS:

where t is shear stress (N/m2), ρ is density of flowing water, g is gravity on Earth, D is average water depth, and WSS is Water Surface Slope. This is analogous to the basal shear stress commonly used in glaciology. Increases in slope, depth, or density of water increase the water's potential to cause erosion.

A raised coral atoll or uplifted coral atoll is an atoll that has been lifted high enough above sea level by tectonic forces, protecting it from scouring by storms and enabling soils and diverse – often endemic – species of flora and fauna to develop. With the exception of Aldabra in the Indian Ocean and Henderson Island in the Pacific Ocean, most tropical raised atolls have been dramatically altered by human activities such as species introduction, phosphate mining, and even bomb testing.