The mainland islands (examples will be given below) - this is part of the land that was previously part of the continent, and later separated from it. This occurs as a result of various hydrological or geological processes. As a rule, the mainland and the island have a fairly similar relief. They are separated by water areas, such as offshore seas and straits. The observation of scientists shows that the distance between the main land area and the island can vary. This is due to the mobility of the earth's crust.
Islands of mainland origin are divided into several types. All of them are connected with their continents at the genetic level. However, despite this, the flora and fauna of such islands may vary significantly. So, let's look at the types of islands depending on their origin.
Platform mainland islands
Platform islands, in fact, are a continuation of the continent. They lie on the mainland shallows and are separated from the main land by various water areas, such as straits and seas. The islands of the Canadian archipelago, Severnaya Zemlya, Svalbard and the British have such an origin. These land areas practically do not differ from the mainland in plant and animal life. And this is due to the fact that they are formed relatively recently.
Mainland slope islands
The second type is the islands of the mainland slope. They are not much different from the first, but their break with the continent took place a little earlier. Unlike the platform ones, their separation from the main land occurred due to deep tectonic splits, and not deflections, as in the first case. A continental island of this kind is separated from the continent by an ocean-type strait. Vivid examples are about. Greenland and Fr. Madagascar.
Orogenic Islands
The third type is orogenic islands. These land areas are formed from the continuation of the mountain folds of the mainland. These include New Zealand, Tasmania, about. Nova Zemlya, which, in fact, is a continuation of the Ural Mountains. They are all orogenic continental islands. Examples may continue on. Sakhalin, which is a continuation of the Far Eastern mountain range.
Island arcs
And finally, the most active type of mainland islands are island arcs. They are in large numbers located on the coast of East Asia, Central America and between South America and Antarctica. These include the Japanese island arc, Aleutian, Philippine and others. It is worth noting that it is these land areas that are currently located in the area of high activity of the earth's crust.
Features
Due to its remoteness from the main continent and complete isolation from other lands, the mainland island has a high level of endemic flora and fauna. The sooner he separated from the mainland, the more peculiar his flora and fauna. Islands such as Hawaii, Novaya Zemlya are located at a considerable distance from their continents. This led to the formation of more than 70% of endemic species in the flora and fauna of these lands. Also on the islands live representatives of the animal world, which have some deviations from the usual norms. For example, gigantism in reptiles and, conversely, island mammals are usually smaller than on the mainland. The first group includes Komodo lizards and Galapagos turtles - they are unusually large. The second includes various species of ungulates.
Tasmania island
The mainland island of Tasmania is separated from the continent by the Bass Strait. Its geological structure and relief allow us to say that this is a continuation of the East Australian Mountains. The island is characterized by a peculiar fauna. There are animals from Antarctica, as well as a number of some representatives, long destroyed on the mainland.
New Earth
Archipelago Novaya Zemlya is also ranked by the scientists as the mainland type. The main islands are separated from each other by the narrow Strait of Matochkin Shar. Another archipelago is washed by the Kara Gate, which separates it from the island of Vaigach.
Sakhalin island
Sakhalin Island is a mainland island. Located off the east coast of Asia. It is separated by the Laperouse Strait from about. Hakkaido, whose minimum width is 40 km, as well as the Tatarsky (from the mainland) and Nevelsky. The latter freezes in winter and has a width of not more than 8 km.
New Zealand Islands
The islands of New Zealand are of mainland origin. The arc on which they are located is from New Guinea to the entire length of Australia. There are many faults in New Zealand, followed by volcanic eruptions and earthquakes.
After reviewing the information in the article, everyone will be able to correctly answer which islands are mainland.