Origin of the islands of Oceania. Oceania is. Geological structure and relief of Oceania

Composition, geological structure, relief and minerals

Between Southeast Asia and America huge water area Pacific Ocean occupies the world's largest cluster of islands. There are more than $10$ thousand. This Oceania.

Definition 1

Oceania are islands and archipelagos located in the central and southwestern Pacific Ocean

This island land has a total area of about $1.3 million square km, which is only $2% of the ocean area. The geographical location of the islands, as well as their size and relief, are most directly related to their origin.

The genesis of the islands allows us to identify $4 $ main types:

Mainland Islands;
Volcanic Islands;
Biogenic islands;
Geosynclinal islands.

To the islands mainland of origin include the largest in area – New Guinea, New Zealand , which account for $80$% of Oceania's land area. The topography of these islands includes mountain ranges and vast low-lying plains. Hawaiian islands, for example, are typical volcanic, A coral reefs and atolls have biogenic origin.

Definition 2

Atolls- These are flat, low ring-shaped islands in the middle with a lagoon connected to the ocean.

Example atolls are the islands of Central Polynesia - Tuamotu archipelago, atoll Kwajalein having the world's largest lagoon in the archipelago Marshall Islands. Coral islands were formed in quaternary period when sections of the Pacific Ocean floor subsided. In the western part of Oceania lie geosynclinal islands. Most of the islands have volcanic origins, and some represent the pinnacles underwater volcanoes – Samoa, Cook, Easter, Marquesas Islands. Minerals are distributed extremely widely across the islands unevenly, and on many of them it’s just none. Development is carried out only on the largest ones. New Caledonia has nickel reserves, there is oil and gas New Guinea and New Zealand. New Guinea still has reserves copper and gold. Phosphorite reserves have been discovered at island atolls. As a nitrogen and phosphorus fertilizer, active development was carried out in the past on many island atolls. guano– decomposed droppings of seabirds.

Note 1

In Oceania, based on regional landscape differences, $4$ physical and geographical countries are distinguished:

Melanesia. It includes New Guinea, the archipelagos of Bismarck, Louisaide, Solomon islands, New Hebrides, New Caledonia, Fiji, etc.
Micronesia. It has $1,500 islands - among them the archipelagos of Kazan, Mariana, Caroline, Marshall Islands, Gilbert Islands, Nauru. They are all small in area.
New Zealand;
Polynesia. " Poly» – a lot of islands. Polynesia can be described as a triangle whose corners are Hawaii-New Zealand-Easter Island.

Oceania Climate

Note 2

Oceania lies within the $3 main and $2 transition climate zones:

Equatorial belt;
Subequatorial belt;
Tropical zone;
Subtropical zone;
Temperate zone.

Predominant on the islands tropical climate, and subequatorial dominates near Australia and Asia. West of the $180$ meridian the islands lie in equatorial climate, and in subtropical climate lie islands located north and south of the tropics. Moderate The belt occupies most of New Zealand. The climate of the islands is determined mainly trade winds, which means that they receive heavy rainfall. During the year, precipitation can vary from $1500$-$4000$ mm. The topography of some islands and their leeward sides reduce precipitation, and the climate may be drier or wetter. One of the most wet places on the planet located precisely in Oceania on the eastern slope of the mountain Waialeale– $11430$ mm per year. The mountain is located on an island Kauai, where in $1982 $16,916 mm fell - this was an absolute maximum. average temperature near the tropics +$23$ degrees, and near the equator +$27$. The difference between summer and in winter here is insignificant. Two ocean currents El Niño And La Niña influence the climate of Oceania big influence. Flow El Niño due to the fact that the intertropical convergence zone is moving towards equator, i.e. to the north, at La Nina the movement goes to the south, i.e. from the equator A. In the first case, abundant rains, in the second case – there is a strong drought. The river system of islands is related to the climate. Large rivers only available in New Zealand – Waikato River and New Guinea - Sepik and Fly rivers. Rivers are naturally fed rain, and recharge comes from melting glaciers. On the river atolls none at all. Lakes, including thermal, are situated in New Zealand, is here and geysers. Lakes on other islands of Oceania are very rare.

Nature of Oceania

The distance from the continents, the small size of the islands and the vast expanse of water around them significantly influenced the nature and life of peoples. The centers of flora formation were large islands, but at the same time many species of plants from Australia, the Malay Archipelago and Southeast Asia migrated to the islands.

Note 3

As a result, Oceania is included in Paleotropical area of vegetation in which $3$ subareas are distinguished:

Malesian floristic subregion;
Hawaiian Subregion;
New Zealand subregion.

Malesian The subregion is characterized by numerous tropical families - pandanus, ficus, water lilies, bananas, laurel and widespread legumes. There are many epiphytes here - ferns, orchids.

Hawaiian The subregion is represented by one genus of palms, a small number of orchids, and the absence of gymnosperms and ficus. But there are a lot of ferns here. These are the first plants to settle in the cracks of cooled lava flows.

For New Zealand In the subregion there will be numerous species of Asteraceae, ferns, sedges, and grasses.

The most common plants in Oceania are coconut palms and breadfruit trees. Their fruits are used for food, and their wood is a source of heat and building material. The endosperm of coconut palm nuts is the source copra, and it is the basis of exports to the countries of Oceania. On Hawaiian Islands and in New Zealand there are endemics flora and fauna. Coral the islands have very poor species composition. Cultivated plants include pineapples, bananas, and sugar cane. The composition of the fauna has specific features that are associated with ocean spaces, causing difficulties for the settlement of animals. Species composition of fauna poor, complete absence mammals. In this regard, a significant part of Oceania is allocated to Polynesian zoogeographic region. There are many flying birds - swifts, pigeons. Small animals include bats, dogs, foxes, lizards. Insects are accidentally carried on the trunks of floating trees. In New Zealand, a representative of the fauna is kiwi – national symbol countries. Among the endemics are kea or nestor, kakapo or owl parrot, takahe or wingless sultana.

Note 4

Oceania developed under conditions of long-term isolation from mainland land. This determined originality its landscapes, manifested in the geological structure and relief, in the high endemism and poverty of species composition of flora and fauna. These reasons provide grounds for singling out Oceania as special part of the world has no analogues on the continents.

The message Oceania 7th grade will briefly tell you a lot useful information about this geographical region of the world. Also, information about Oceania report will help deepen your knowledge of geography.

Message about Oceania

Oceania is a separate part of the geopolitical region. It consists of a large number of atolls and islands that are located in the central and western parts of the Pacific Ocean.

Oceania: brief description

Oceania is located between the subtropical latitudes of the Northern Hemisphere and the temperate latitudes of the Southern Hemisphere. Geographers often consider Oceania as part of Australia. For this there is geographical name, which sounds like Australia and Oceania. total area geopolitical region is 1.24 million km 2. It is inhabited by 10.6 million people.

Oceania is divided into 3 geographical regions: Micronesia, Polynesia and Melanesia. It is washed by such seas of the Pacific Ocean as the Solomon, Coral, New Guinea, Koro and Fiji, and Tasman Sea. And the Arafura Sea, which belongs to the Indian Ocean basin.

Climatic features of Oceania

Most of Oceania is dominated by a tropical climate and heavy annual rainfall. The islands, which are located closer to the tropical zone, are characterized by an average annual temperature of +23 °C. In the area near the equator - 27 °C. The climate of the geopolitical region is influenced by El Niño and La Niña currents. Most of the islands are susceptible to the negative effects of tsunamis, active volcanoes and typhoons.

Oceania differs from other regions in the dramatic change weather conditions: heavy rains give way to prolonged drought.

Minerals of Oceania

Mineral deposits are determined by the geological structure and origin of the islands. The New Caledonia region produces nickel, chromite and other metals. New Guinea has reserves of bauxite, coal and oil. The atoll islands are rich in phosphorites.

Flora and fauna of Oceania

The large islands are covered with moist evergreen forests or savannas. The predominant trees are pandanus, bamboos, ficus, and casuarinas. Some types of trees are useful for human activity - sago and coconut palms, mangoes and bananas, melon and breadfruit. Also on the islands of Oceania there are endemic species: tree ferns, kauri pine, New Zealand flax and cabbage tree.

The fauna is represented by echidnas, tree kangaroos, crocodiles, and kiwi birds. There are no predators or poisonous snakes on the islands, and there are practically no mammals. Europeans brought pigs, cows, horses, goats, rabbits, and cats to Oceania.

The indigenous inhabitants of Oceania are representatives of the Australoid-Mongoloid race.
Here is the country of Karibati, which lies in all hemispheres.
The region is located active volcano, not fading since 1902.
Hadeaway Island is unique in that it has an underwater post office, the only one in the world.
In the past, the inhabitants of Oceania practiced cannibalism.

We hope that the report on the topic “Oceania” helped you learn a lot of useful information about this part of the world. You can add a message on the topic “Oceania” using the comment form below.

Ocean islands are the most exotic and unusual travel destination. It is enough that when a fierce winter is raging in our homeland, it is the height of summer in the Southern Hemisphere. And even though people there don’t walk upside down, and the water doesn’t swirl in reverse side, the lands of Oceania remain a real terra incognita for many.

What is Oceania?

The boundaries of Oceania are quite arbitrary. It is essentially a cluster of islands in the central and western Pacific Ocean. Eastern point They consider Easter Island, and the western one is New Guinea. Geographers combine Oceania with Australia and consider these lands to be a separate part of the world.

The rather long list includes islands such as New Zealand, New Guinea, Fiji, Easter, Solomon, Hawaii and many others. Most of the islands were formed by volcanic activity, and many fire-breathing mountains still pose a danger.

Papua New Guinea

Papua New Guinea covers an area comparable in area to Sweden and actually connects Australia and Asia. Long before European sailors and Miklouho-Maclay, Indonesian rulers sent their envoys here to hunt for exotic birds and labor. The name of the island was given by the Portuguese Don Jorge de Menezes, clearly alluding to the hair of the aborigines: “Papua” means “curly” in Malay. More than 820 languages are spoken here - this is due to some isolation of the tribes from each other due to the mountainous terrain.

Fiji

Fiji is an archipelago of 332 islands, of which only a third are inhabited. Europeans discovered the Fiji Islands in the 17th century, but did not risk establishing colonies there until the 19th century. There was only one reason - cannibalism of the aborigines. The leader had unquestioned authority and power. In the villages, a respectful attitude towards the head of the tribe is still preserved: only he is allowed to wear sunglasses and hats. But as for tourists... it is difficult to find more hospitable people. Here you will be treated to the most unusual dishes: boiled bat, stew in banana leaves and even fried snake. However, beauty tropical forests and diverse underwater world Fiji, for which it is highly valued by divers, is short-lived: due to climate change, the corals to which the island owes its origin are under threat - environmental communities are sounding the alarm.

New Zealand

New Zealand (or "Land of the Long White Cloud") was discovered in 1642 by the Dutch sailor Abel Tasman. The local tribes at that time definitely did not like the white-skinned Europeans... It is now New Zealand that is considered the most safe country peace. The next person to venture here was James Cook in 1769, and he also contributed to the inclusion new country into English possessions. The symbol of the island is the wingless, timid kiwi bird - that’s what New Zealanders call themselves. Well, Tolkien fans cannot help but know that all parts of the Lord of the Rings trilogy were filmed in local landscapes, and during special tours you can see Hobbiton and the Baggins’ home with your own eyes.

Solomon islands

The Solomon Islands are little known in the world. This is due to the distance from others geographical objects. Meanwhile, there is a constant mild climate and uniquely beautiful nature. For example, to the list World Heritage UNESCO is about to include the Marovo salt lagoon with sparkling blue water - the largest in the world. There is also the highest coral island - East Rennell. Tengano is so big freshwater lake in the southern hemisphere, which includes 200 islands. As for the inhabitants, their manners and habits are quite curious. For example, many of them still worship sharks. The Aborigines before the arrival of missionaries were primarily headhunters. By the way, about 10% of dark-skinned Solomon Islanders are blond. The reason for this is a mutation that appeared many centuries ago - it has nothing to do with European settlements.

Animal and plant life

The flora and fauna of the islands of Oceania amaze the imagination of experienced tourists with their exoticism. What a breadfruit tree is worth! “He who plants a breadfruit tree will do more to feed his descendants than a farmer who spends his whole life cultivating the field by the sweat of his brow,” wrote James Cook. One plant can produce up to 700-800 “breads” - special fruits with sweetish pulp, from which peculiar rolls are “baked”. Sago palms in New Guinea provide starch that is used to make delicious pancakes. In abundance in tropical forests you can find cake trees - the sweet taste of their fruit is truly reminiscent of confectionery. Well, there are countless bananas and coconuts - without these fruits the aborigines would not be able to survive.

People with entomophobia - fear of insects - have nothing to do on the islands of Oceania. Huge spiders, poisonous flies and giant butterflies are quite capable of frightening and even causing harm. In the jungle there is a danger of stepping on a snake - or it will dive from the branch itself. In contrast to the dangers, there is the indescribable beauty of birds of paradise and the touching faces of marsupials. By the way, opossums, as many people mistakenly believe, are not found in Oceania: possums live there. This confusion arose during the research of James Cook - the expedition biologist attributed marsupials to opossums living in America.

Go diving, lie on the best coral beaches in the world, ride alpine skiing, see a parrot in natural environment habitats and have the most romantic wedding - this is not a complete list of what newly opened hotels offer tourists Oceania islands.

Pavilion “Around the World. Asia, Africa, Latin America, Australia and Oceania"

ETHNOMIR, Kaluga region, Borovsky district, Petrovo village

In the ethnographic park-museum "ETNOMIR" - amazing place. The “City” street is built inside a spacious pavilion, so Mira Street is always warm, light and good weather- just right for an exciting walk, especially since within the framework of the latter you can complete a whole trip around the world. Like any street popular with tourists, it has its own attractions, workshops, street artisans, cafes and shops located inside and outside the 19 houses.

The facades of the buildings are made in different ethnic styles. Each house is a “quote” from the life and traditions of a certain country. The very appearance of the houses begins the story of distant lands.

Step inside and you will be surrounded by new, unfamiliar objects, sounds and smells. The color scheme and decoration, furniture, interior and household items - all this helps to plunge into the atmosphere of distant countries, to understand and feel their uniqueness.

Oceania is the name of a region of the world consisting of island groups in the central and southern Pacific Ocean. It covers more than 8.5 million km². Some of the countries that make up Oceania include Australia, New Zealand, Tuvalu, Samoa, Tonga, Papua New Guinea, Solomon Islands, Vanuatu, Fiji, Palau, Micronesia, Marshall Islands, Kiribati and Nauru. Oceania also includes several dependent territories such as American Samoa, Johnston and French Polynesia.

Physical geography of Oceania

In terms of physical geography, the islands of Oceania are often divided into four different subregions based on the geological processes that played an important role in their physical development. The first one is. It stands out due to its location in the middle of the Indo-Australian plate, and the lack of mountain building during its development. Instead, the current physical features of Australia's landscape have been shaped primarily by erosion.

The second region of Oceania consists of islands located at the boundaries of the collision between the plates of the earth's crust. They are located in the South Pacific Ocean. For example, on the collision line between the Indo-Australian and Pacific plates, and includes places such as New Zealand, Papua New Guinea and the Solomon Islands. Northern part The Pacific Ocean also has similar types of landscapes along the boundary of the Eurasian and Pacific plates. Colliding tectonic plates are responsible for the formation of mountains, such as those in New Zealand, that rise more than 3,000 m above sea level.

Volcanic islands such as Fiji are the third category of landscape type found in Oceania. These islands typically rise from the sea floor in hot spots in the Pacific Ocean basin. Most of these areas consist of very small islands with high mountain ranges.

Finally, island coral reefs and atolls such as Tuvalu are the final type of landscape in Oceania. Atolls are specifically responsible for the formation of low-lying land areas, some with enclosed lagoons.

Oceania Climate

Climate map of Oceania according to Köppen

Most of Oceania is divided into two climatic zones: temperate and. Most of Australia and all of New Zealand are in the temperate zone, while most of the Pacific islands are considered tropical. Temperate regions of Oceania have high levels precipitation, cold winters and warm or hot summers. The tropical regions of Oceania are hot and humid all year round.

In addition to these climate zones, most countries in Oceania are subject to continuous trade winds and sometimes hurricanes (called tropical cyclones), which have historically caused catastrophic damage to the countries and islands of the region.

Flora and fauna of Oceania

Since most of Oceania lies in tropical or temperate climatic zone, abundant rainfall supports the growth of humid and temperate rainforests throughout the region. Tropical rainforests are common in some island countries, near the tropics, while temperate rainforests are found in New Zealand. Both types of forest support a variety of animal and plant species, making Oceania one of the most biologically diverse regions in the world.

It is important to note that not all areas of Oceania receive high rainfall and some parts of the region are arid or semi-arid. Australia, for example, has large areas of dry land that support little diversity of flora. In addition, El Niño has caused frequent droughts in recent decades in Northern Australia and Papua New Guinea.

The fauna of Oceania, like its flora, is also extremely beautiful. Because much of the region is made up of islands, unique species of birds, animals and insects have evolved in complete isolation. Presence of coral reefs such as the Great barrier reef and Kingman Reef also provide areas of high concentrations of flora and fauna and are considered biodiversity hotspots.

Population of Oceania

Oceania has a population of about 40 million, with the bulk of the people (about 30 million) living in Australia and New Zealand, while Papua New Guinea has a population of about 8 million. The remainder of Oceania's population is scattered across the various islands that make up the region.

Like population distribution, urbanization and industrialization are also unevenly distributed across Oceania. About 89% of the region's urban areas are in Australia and New Zealand, and these countries also have the best developed infrastructure. Australia, in particular, has reserves of many minerals and energy feedstocks, and generates much of the region's economy. The rest of Oceania and, in particular, the Pacific island states are very underdeveloped. Some islands are rich, but most are not. In addition, some of island states experience a shortage of clean drinking water or food.

Agriculture is also important in Oceania and there are three types that are common in the region. These include natural Agriculture, plantation crops and capital-intensive agriculture. Subsistence farming occurs on most Pacific Islands and is carried out to support local communities. Cassava, taro, yams and sweet potatoes are the most common products of this type of agriculture. Plantation crops are planted in the middle tropical islands, while capital-intensive agriculture is practiced only in Australia and New Zealand.

And finally, fishing and tourism are important sectors of the Oceanian economy and a driver of its development. Fishing serves as an important source of income because many islands have maritime exclusive economic zones that extend over 370 km. Tourism is also important for Oceania as tropical islands, for example, Fiji offers aesthetic beauty, while Australia and New Zealand attract developed cities with modern infrastructure. New Zealand has also become an important tourism region in the field.

Oceania countries

Map of Oceania countries/Wikipedia

Below is a list of the 14 independent countries of Oceania, ranked from largest to smallest country by area:

1) Australia:

Area: 7,617,930 km²
Population: about 25,000,000 people
Capital: Canberra

2) Papua New Guinea:

Area: 462,840 km²
Population: more than 8,000,000 people
Capital: Port Moresby

3) New Zealand:

Area: 268,680 km²
Population: about 5,000,000 people
Capital: Wellington

4) Solomon Islands:

Area: 28,450 km²
Population: about 600,000 people
Capitals: Honiara

5) Fiji:

Area: 18,274 km²
Population: about 900,000 people
Capital: Suva

6) Vanuatu:

Area: 12,189 km²
Population: about 270,000 people
Capital: Port Vila

7) Samoa:

Area: 2842 km²
Population: about 193,000 people
Capital: Apia

8) Kiribati:

Area: 811 km²
Population: about 110,000 people
Capital: Tarawa

9) Tonga:

Area: 748 km²
Population: about 107,000 people
Capitals: Nuku'alofa

10) Federated States of Micronesia:

Area: 702 km²
Population: about 105,000 people
Capital: Palikir

11) Palau:

Area: 459 km²
Population: about 21,000 people
Capital: Melekeok

12) Marshall Islands:

Area: 181 km²
Population: about 53,000 people
Capital: Majuro

13) Tuvalu:

Area: 26 km²
Capital: Funafuti

14) Nauru:

Area: 21 km²
Population: about 11,000 people
Capital: No

Between 28°N and 53° S; 130°E and 105°W This island world includes almost 7 thousand islands. The total area of the island land of Oceania is about 1.3 million km2. This is only 2% of the area of the Pacific Ocean.

Geographical location, size and topography of the islands closely related to their origin. According to their genesis, the islands of Oceania belong to four main types: continental, biogenic and geosynclinal, which arise in contact zones - island arcs.

The mainland islands are the most significant in area (,). Mountain ranges they are combined with vast low-lying plains and plateaus. are a typical example of islands of volcanic origin. Coral reefs and atolls are of biogenic origin. Atolls are flat, low, ring-shaped islands with a lagoon in the middle connected to the ocean. Such are, for example, the islands of Central Polynesia (the Tuamotu archipelago is the largest collection of atolls in the world). Geosynclinal island arcs lie in western Oceania. The relief of islands of this type is a combination of mountains and. Such, for example, is the island of New Caledonia, stretching for more than 400 km.

Oceania is determined by the origin of the islands. Thus, New Caledonia is characterized by rich deposits of chromite and a number of other metals. , bauxite and oil are mined in New Guinea. Phosphorite deposits have been discovered on the atoll islands.

Oceania islands determined geographical location territory and the moderating influence of the ocean. The main archipelagos of the islands lie in the equatorial, and tropical zones Northern and Southern Hemispheres. Only the islands adjacent to it are located in and belts. Average monthly values of the warmest month vary from +25°C in the north to +16° in the south; the coldest - from +16° in the north to +5°C in the south. , Caroline and Mariana Islands, as well as New Guinea, lie in a zone where the temperature is about +26°C all year round. The moderating influence of the ocean affects minor temperature fluctuations between seasons and during the day. There is a lot of precipitation, on average 3000-4000 mm. They are especially abundant in the western part of Oceania, where mountains of mainland islands stand in the way of trade winds from the ocean. However, one of the wettest places on Earth is in the Hawaiian Islands, where up to 12,500 mm of precipitation per year falls on the windward slopes of the volcanoes.

Species composition and animal world poor and unique due to the remoteness and isolation of the islands of Oceania from the rest of the land. Large islands Oceania is covered predominantly with evergreens (on windward slopes) or. Here the trees are dominated by ficus, pandanus, bamboos, and casuarinas. There are many valuable trees and plants useful to humans: coconut and sago palms, bread and melon trees, rubber plants, bananas and mangoes. The forests of New Zealand contain many endemic species: special types of tree ferns, pine trees (kauri pine is one of the giant trees globe), cabbage tree, New Zealand flax, etc.

The fauna is also unique. It is richer and more diverse on the islands closer to Australia. Thus, the echidna and tree kangaroo are common in New Guinea, and crocodiles are found there. New Zealand is home to the running bird, not the flying one, the kiwi. Among the land animals on the islands of Oceania there are almost no mammals, there have never been predators, and there are no poisonous snakes. The coastal waters and lagoons of the islands are unusually rich in various forms of life.

Livestock (cows, pigs, horses), as well as a number of cosmopolitan animals from other parts of the world, were brought to Oceania. Rats have multiplied on the islands, cats have gone wild; goats and rabbits destroyed a significant part of the vegetation, which led to the loss of cover. Irrational use of land, deforestation, pollution of coastal waters, transformation of some islands into military testing grounds nuclear weapons disrupt the natural balance on the islands of Oceania.

Population Oceania , amounting to about 10 million people, represented by indigenous people, migrants and a mixed population. The Papuans, who belong to the equatorial race, live on New Guinea and the adjacent islands. Indigenous people New Zealand (Maori) and other islands of Oceania belong to a special Polynesian group of peoples occupying an intermediate position between the three main races of humanity. These peoples have lighter skin and wavy hair than the Papuans. It is still not entirely clear where and by what routes many millennia ago the Polynesians settled the main archipelagos of the islands of Oceania. The newcomer population are immigrants from Europe, Asia and America. Thus, Anglo-New Zealanders make up 3/4 of the population of this country, and the indigenous people - Maori - only 9%. However, on other islands of Oceania, indigenous people (as opposed to Australia) make up the majority of the population.

Residents of Oceania traditionally engage in fishing. In New Zealand, European settlers raise sheep and cattle; meat, wool and butter are the main export products.

Political map Oceania was formed as a result of the seizure of the islands by European and American colonialists in the 19th-20th centuries. Three decades ago, there was only one independent state in Oceania - New Zealand. Now politically independent Micronesia consists of many (more than 1500 of them!) small islands in the western Pacific Ocean north of (Mariana, Marshall, Caroline Islands and etc.). New Zealand is included in a special region of Oceania. And not only according to natural and ethnographic conditions, but also taking into account the level economic development throughout Oceania.

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