The Indian Ocean is the third largest ocean on earth. The Indian Ocean washes three continents at once: Africa from the east, Asia from the south, Australia from the north and northwest. The name Indian Ocean is found already at the beginning of the sixteenth century by Schöner under the name Oceanus orientalis indicus, in contrast to the Atlantic Ocean, then known as Oceanus occidentalis.

In the northwest and north, that is, from the side of Africa and Eurasia, large peninsulas cut into the Indian Ocean, separating a number of seas and bays of different origin, different depth and bottom structure. These are the Somali and Arabian peninsulas, limiting the Red Sea and the Gulf of Aden, interconnected by the Bab el-Mandeb Strait. Farther to the east, between the Arabian Sea and the Bay of Bengal, which is in fact also a marginal sea, the triangular block of the Hindustan peninsula protrudes far into the ocean. The Arabian Sea through the Gulf of Oman and the Strait of Hormuz connects with the Persian Gulf, which is actually inland sea Indian Ocean.

Like the Red Sea, the Persian Gulf stretches from the southeast to the northwest. These are the most northerly parts of the Indian Ocean. Only in contrast to the narrow and deep graben of the Red Sea, the Persian Gulf is located entirely within the shelf, occupying part of the Mesopotamian foredeep. In other areas, the shelf of the Indian Ocean has a width of no more than 100 km. An exception is the shelf of Northern, Northwestern and Western Australia, including also the shelf of the Great Australian Gulf.

Fig.1. Indian Ocean

To the east and southeast of the Bay of Bengal, the Indian Ocean includes the Andaman Sea between the Andaman and Nicobar Islands, Sumatra and the peninsulas of Indochina and Malacca, as well as the Arafura and Timor Seas, located mainly within the Sahul (northern) shelf of Australia. In the south, the Indian Ocean freely connects with the Pacific and Atlantic oceans. The conditional boundaries between them are drawn, respectively, along 147 ° E. and 20° E

There are few large mainland islands in the Indian Ocean. They are located at short distances from the continents of which they are parts. Only the largest among them - Madagascar (the fourth largest island on Earth) - is separated from Africa by the Mozambique Strait, 400 km wide. The Indian Ocean also includes part of the islands of the Sunda Archipelago - Sumatra, Java, etc. To the southeast, in the immediate vicinity of Hindustan, is the island of Sri Lanka. Numerous islands and archipelagos of volcanic origin are scattered in the open part of the Indian Ocean. In the northern part of the ocean, many of them are crowned with coral structures.

History of the Indian Ocean

The history of the study of the Indian Ocean can be divided into three periods: from merchant shipping and military campaigns of ancient times to the beginning of deep-sea research in the last quarter of the 18th century. early XIX century.; from research expeditions of the last quarter of the 17th - 19th centuries to the first integrated oceanographic expeditions of the last quarter of the 19th century; from these expeditions to complex international studies our time included.

In the first period, the peoples who lived on the shores of the Indian Ocean traveled for trading purposes, creating maps along the way and gaining knowledge about currents, winds and other navigation conditions.

One of the brightest events is the journey of the Tver merchant Athanasius Nikitin to India in 1466-1472. A great contribution was also made by D. Cook, who sailed along the coast on the ships "Resolution" and "Adventure" in 1772-1775, during his journey he obtained data on the temperature of the water to a depth of 180 m. Oceanographic research was also carried out by I. F. Kruzenshtern and Yu. F. Lisyansky (1803-1806). The next important contribution was the research of Charles Darwin, who received geological, ecological and biological data. At the same time, Darwin formed the theory of the origin of atolls, which is still valid. The first deep-sea soundings of the Indian Ocean (up to 5000 m) were probably made by D. Ross in 1840-1843. The development of deep-sea research was also facilitated by the work on laying underwater telegraph cables.

The beginning of the second period of the study of the Indian Ocean was marked in 1873-1876. the first round-the-world oceanographic expedition "Challenger" under the leadership of Professor Wyville Thomson, a member of the British Royal Society. This expedition carried out comprehensive research, including physical, chemical, biological and geological observations.

This was followed by a series of studies, already of a narrower focus, it is significant that a large number of countries that are leaders in science participated in the study of the Indian Ocean. Subsequent studies were of a narrower nature (for example, gravimetric studies on submarines in 1923 by Vening-Mason).

Expedition activities within the framework of the International Geophysical Year (IGY) 1957-1959. opened new stage in the study of the oceans. Although this expedition paid the most attention to the Atlantic and Pacific Ocean, Indian also did not stand aside. The largest expedition at that time was the program of the International Indian Ocean Expedition (IIOE), which covered almost the entire Indian Ocean (1960-1965) with observation. It is very pleasant that 10 Soviet ships took part in this program.

Exploration of the continental margins of the Indian Ocean

A detailed study of the continental margins has a relatively short history (about 50 years), even despite the many efforts made, many aspects remain unclear and contradictory. Submarine continental margins are among the areas in which it is most difficult to work, since they are characterized by significant fluctuations in the depths of the bottom and the configuration of the layers of the sedimentary cover and crust, large differences physical properties and significant changes in the composition of rocks within the same region.

Ancient underwater margins are even more difficult to identify and study, because they are characterized by severe deformations. Therefore, there is a wide range of possible, acceptable interpretations and concepts of origin and evolution. It is much easier to explore deep ocean basins, where the water column reaches 4-5 km, which serve as a filter to eliminate the influence of problematic areas on geophysical curves, the structure of such areas is much simpler than those that are closer to the coast.

Objects of study, goals and objectives of research

In the middle of the 20th century, global international research in the field of geology began. Of course, experiments and expeditions were also carried out at an earlier time, but all of them had rather broad tasks and were rather generalized. The need for more narrow observations became apparent when more advanced instruments and methods began to appear that made it possible to record the most accurate results. However, there were more pressing reasons. Thus, on the example of the expeditions carried out within the framework of the International Geophysical Year (1957-1959), one of the tasks of which was to study the possibilities of the recreational and food resources of the Indian Ocean, the need of people to modernize the public and social sphere is clearly expressed. So, the object of study is the continent-ocean transition zones and the processes taking place in these areas.

By definition, the subject of study is the characteristics of the objects of study. There are three main types of margins: passive, active, transform. Sometimes, the structure of the outskirts introduces difficulty when trying to attribute it to one of three types, but modern methods allow for a more or less precise determination. sedimentation, tectonic movements, shelf formation - all these are the characteristics of the processes, and therefore also the subject of study.

The goal of researchers, at present, is to collect information about the margins of the Indian Ocean, this is understood as a complex of systematized knowledge. For example, thanks to a detailed study of the continent-ocean transition zones, scientists are able to restore the picture of the past. As a result of a number of experiments, it is possible to establish the causes and consequences of certain events in the geological history of the Earth. For example, it was possible to establish that the Indian Ocean was formed at the junction of the Jurassic and Cretaceous periods as a result of the breakup of Gondwana. Then there was a separation of Africa and the Deccan from Australia with Antarctica, and later - Australia from Antarctica (in the Paleogene, about 50 million years ago).

As tasks, one should single out the integration of the Earth sciences and knowledge of applied sciences, into a specific problem - the geology of continental margins. Using modern technology and a wide range of methods to obtain more accurate results.

Introduction

I chose this topic for several reasons. In my opinion, the Indian Ocean and its margins represent a huge scientific interest. From the point of view of geology, a lot of interesting objects can be distinguished here. Such as: the Sunda Island Arc, the triple junction point of Rodrigues Island, the Bengal alluvial fan, the Karoo deposits on the east coast of Africa, and much more.

From the perspective of research in this region, it must be said that the Indian Ocean and its shores remain poorly understood. Despite numerous studies, many controversial issues remain. One of them is the question of the origin of the ocean. Personally, I found several points of view on this matter, and this interested me. We are talking about the age of the ocean, disputes arising on this occasion are associated with the finds of remains related to different period, in layers with assumed equal ages.

In order to fully understand the reasons for choosing this particular topic, its relevance and prospects, it is necessary to raise the question of what goals were set for the research, the result of which is presented here. In my opinion, any scientific activity should be of some public benefit. In the case of coastal exploration, the benefits are clear. Since ancient times, when expeditions were devoted to mapping hitherto unexplored territories, the study of the outskirts of both the Indian and any other ocean has been a source of progress, as a result, the development of trade and diplomatic relations. AT modern world research is even more important. Having received data on food and mineral resources, humanity can begin to rationalize their use. Whether it's oil, natural gas or just fishing, it's all directly related to the geology of the margins.

My goal was to write a term paper on the chosen topic.

My task was to study the continent-ocean transition zones, using the example of the Indian Ocean, by reading the literature on this topic. The task was also to process, comprehend the acquired knowledge and convey it in their own words.

Historical overview

Indian Ocean exploration

The Indian Ocean is the third largest ocean on earth. The Indian Ocean washes three continents at once: Africa from the east, Asia from the south, Australia from the north and northwest.

The name Indian Ocean is found already at the beginning of the sixteenth century by Schöner under the name Oceanus orientalis indicus, in contrast to the Atlantic Ocean, then known as Oceanus occidentalis (http://www.vehi.net/brokgauz/).

The history of the study of the Indian Ocean can be divided into three periods: from merchant shipping and military campaigns of ancient times to the beginning of deep-sea research in the last quarter. XVIII-beginning XIX century.; from research expeditions of the last quarter of the 17th - 19th centuries to the first complex oceanographic expeditions of the last quarter of the 19th century; from these expeditions to complex international studies of our time, inclusive.

One of the brightest events is the journey of the Tver merchant Athanasius Nikitin to India in 1466-1472. A great contribution was also made by D. Cook, who sailed along the coast on the ships "Resolution" and "Adventure" in 1772-1775, during his journey he obtained data on the temperature of the water to a depth of 180 m. Oceanographic research was also carried out by I.F. . Kruzenshtern and Yu.F. Lisyansky (1803-1806). The next important contribution was the research of Charles Darwin, who received geological, ecological and biological data. At the same time, Darwin formed the theory of the origin of atolls, which is still valid. The first deep-sea soundings of the Indian Ocean (up to 5000 m) were probably made by D. Ross in 1840-1843. The development of deep-sea research was also facilitated by the work on laying underwater telegraph cables (http://ru.wikipedia.org/wiki/).

The beginning of the second period of the study of the Indian Ocean was marked in 1873-1876 by the first round-the-world oceanographic expedition of the Challenger, led by Professor Wyville Thomson, a member of the British Royal Society. This expedition carried out comprehensive research, including physical, chemical, biological and geological observations.

Expedition activities within the framework of the International Geophysical Year (IGY) 1957-1959. opened a new stage in the study of the oceans. Although this expedition paid the most attention to the Atlantic and Pacific Oceans, the Indian also did not stand aside. The largest expedition at that time was the program of the International Indian Ocean Expedition (IIOE), which covered almost the entire Indian Ocean (1960-1965) with observation. It is very pleasant that 10 Soviet ships took part in this program (http://geoman.ru/books/item/f00/s00/z0000051/st005.shtml).

Exploration of the continental margins of the Indian Ocean

A detailed study of the continental margins has a relatively short history (about 50 years), even despite the many efforts made, many aspects remain unclear and contradictory. Submarine continental margins are among the areas in which it is most difficult to work, since they are characterized by significant fluctuations in bottom depths and configurations of sedimentary cover and crust layers, large differences in physical properties and significant changes in rock composition within the same region.

02.02.2016

The Indian Ocean began to form about 145 million years ago, between parts of the split supercontinent Gondwana (future Hindustan, Madagascar, Australia and Antarctica). The ocean, located between different parts of the world, which later began to be inhabited by people, was doomed to become a crossroads of trade routes for the most ancient peoples who lived on its shores.

One of the first civilizations that had the skill of navigation, and lived near the Indian Ocean, were the Sumerians, who settled in Mesopotamia in the Persian Gulf. Sea routes between India and Arabia existed as early as the 3rd millennium BC. In addition, it is known that in the 7th-6th centuries BC. the coastal waters of the ocean were mastered by the Phoenicians, who managed to go around Africa, having sailed from the Red Sea.

On the border of our era, the ships of the most developed peoples - Indians, Chinese and Arabs gradually moved along the coast of the ocean, opening up new ways for trade and military purposes. It is known that already in the VIII-X centuries sea route from China to India was well known and actively used. But for Europeans, the Eastern Ocean (the early name of the Indian) for many centuries was an unknown part of the planet.

But already in the IV century BC. famous Alexander Macedonian reached its shores together with the army after a campaign in India. However, after him, for many hundreds of years, only small ships of the ancient Greeks visited these waters for trade with India and China, and their trade turnover was small. Marco Polo became the first European who, in the 13th century, not only sailed across the Indian Ocean from the Malay Peninsula to the Persian Gulf, but also described the voyage in detail in the Book of the Diversity of the World.

Almost two hundred years later, in his book “Journey Beyond Three Seas”, the Russian traveler, merchant Afanasy Nikitin, who arrived in India by sea through the Arabian Sea in 1469, wrote about the ocean. With the advent of modern documentary sources about those distant shores, the Europeans could not but have an interest in the development of Asian lands by sea.

Although the main reason that drove the researchers was, of course, not simple curiosity, but the desire to earn money by reaching the fabulous riches of Hindustan. The most famous failed attempt to find a short sea route to India was the voyage of Christopher Columbus. Unlike Columbus, the Portuguese calculated everything correctly ...

And it is the Portuguese who are considered the first Europeans of our era, who "officially" opened the expanses of the Indian Ocean to Europeans. The first was Bartolomeu Dias, who in 1488 rounded Africa from the south on his ship. To the east, he managed to advance only to the mouth of the river. Great Fish in present-day South Africa. However, he returned to his homeland with invaluable information - there is a sea route to India.

Under the leadership of Dias, after 9 years, the great expedition of Vasco da Gama was equipped. So, at the end of the 15th - beginning of the 16th centuries, Europeans received information about the east coast of Africa, and were finally able to reach Indian Calicut by sea. They also encountered and were forced to interact with the Arab navigators, who had mastered the Indian Ocean a long time ago.

The next stage in the history of the Indian Ocean can be considered the 18th-19th centuries, when its waters began to be of interest not only as "roads", but also as sources of valuable resources. First, the Englishman James Cook, and then other navigators different countries(including Russians) began to study depths, currents, water properties and other parameters.

From the 19th century to the present, oceanographic studies of the Indian Ocean have been carried out with ever more advanced devices. Of course, its bottom and shores have long been clarified, but it is still too early to consider the history of the study completed.

Presentation on the theme "Indian Ocean" in geography for schoolchildren. Consists of nine slides. In the presentation, the Indian Ocean is considered according to the lesson plan: geographical position, history of ocean research, features of the nature of the ocean, types economic activity in the ocean. The project was completed by Evgenia Yagodorova and Daria Malyutkina.

Fragments from the presentation:

Lesson plan:

Geographical position.
From the history of ocean exploration.
Features of the nature of the ocean.
Types of economic activity in the ocean.

Map of the Indian Ocean

The Indian Ocean has a peculiar position on the planet: most of it lies in the southern hemisphere. In the north, it is bounded by Eurasia and has no connection with the Arctic Ocean.

Who discovered and explored the Indian Ocean?

The description of sailing routes on the ocean was the first to be made by the Arabs. Information about the Indian Ocean began to accumulate from the time of the voyages of Vasco da Gama (1497-1499). At the end of the 18th century The first measurements of the depth of this ocean were made by the English navigator J. Cook.

Features of the nature of the ocean

The structure of the bottom topography is complex. Mid-ocean ridges divide the ocean floor into three parts. In the western part, a ridge stretches, connecting south of Africa with the Mid-Atlantic Ridge. The center of the ridge is characterized by deep faults, areas of earthquakes and volcanism at the bottom of the ocean. faults earth's crust continue in the Red Sea and come ashore. A feature of the climate is the seasonal monsoon winds in the northern part of the ocean, which is located in the subequatorial belt and is significantly influenced by land. The monsoons have a huge impact on weather in the northern part of the ocean.

In the south, the ocean experiences the cooling influence of Antarctica; here lie the most severe regions of the ocean. The properties of water masses are associated with the characteristics of the climate. The northern part of the ocean warms up well, is deprived of the influx of cold waters and is therefore the warmest. The water temperature here is higher (up to +30) than at the same latitudes in other oceans. To the south, the water temperature drops. The salinity of ocean waters at the surface is generally higher than the salinity oceans, and in the Red Sea it is especially high (up to 42%). In the northern part of the ocean, the formation of currents is influenced by the seasonal change of winds. Monsoons change the direction of water movement, causing their vertical mixing. Rebuild the flow system. In the south the currents are integral part general scheme currents of the oceans.

Organic world of the Indian Ocean

Tropical water masses are rich in plankton, which is especially rich in unicellular algae. Among the plankton, there are many organisms that glow at night. Diversity of fish species: sardinella, mackerel, sharks. Shelf areas and shallow waters near coral reefs are especially rich in life. Turtles and sea snakes live in warm waters. Of the mollusks, there are many cuttlefish and squid, and near Antarctica - whales and seals.

Types of economic activity

The ocean shelf is rich in minerals. In the strata sedimentary rocks at the bottom of the Persian Gulf, huge deposits of oil create the danger of water pollution. Fishing is also developed. Numerous shipping routes pass through the Indian Ocean. There are especially many sea roads in the northern part of the ocean, where small sailing ships are still used. The direction of their movement is associated with the monsoons.

The project was completed by Evgenia Yagodorova and Daria Malyutkina.

As you know, the territory of our planet is washed by four oceans. The Atlantic and Indian Oceans rank second and third in terms of water volume, respectively.

These oceans are home to unique species of aquatic animals and vegetation.

History of the discovery of the Atlantic Ocean

The development of the Atlantic Ocean began in the era of early Antiquity. It was then that the ancient Phoenician navigators began to make the first trips to the Mediterranean Sea and the eastern coast of the Atlantic Ocean.

However, to cross Atlantic Ocean succeeded only by the European northern peoples in the 9th century. The "golden era" of the exploration of the Atlantic was laid by the famous navigator Christopher Columbus.

During his expeditions, many seas and bays of the Atlantic Ocean were discovered. Modern scientists - oceanologists continue to study the Atlantic Ocean, in particular the relief structures of its bottom.

History of the discovery of the Indian Ocean

The history of the discovery of the Indian Ocean is rooted in the days of ancient civilizations. The ocean served as the main trade route for the Persians, Indians, Egyptians, and Phoenicians.

The Chinese were the first to explore the Indian Ocean. Exactly Chinese navigator Ho's wife managed for the first time during his expedition to explore the shores of Sri Lanka, Arabian Peninsula, Persia and Africa.

The large-scale development of the Indian Ocean began with the first expeditions of the Portuguese Vasco de Gama, who managed not only to reach the coast of India, completely rounding the African coast, but also to discover many islands in the Indian Ocean.

Atlantic Ocean: general information

The Atlantic Ocean is the second largest ocean in the world in terms of its size. Its waters cover an area of 80 million square meters. km.

The formation of the Atlantic Ocean began more than 150 million years ago, at a time when the modern American continent began to separate from Eurasia. The Atlantic Ocean is considered the youngest among all existing oceans.

The maximum depth reaches 9 km(trough, which is located off the coast of Puerto Rico). The Atlantic Ocean washes the shores of such continents: Eurasia, Africa, South and North America as well as Antarctica.

Indian Ocean: general information

Indian Ocean, with an area of about 70 million km. sq., ranks third in size among other oceans. The deepest place in the Indian Ocean is a depression near Java islands(Indonesia), the depth of which reaches 7 km.

The waters of the Indian Ocean are characterized by frequent changes in the direction of the current. The Indian Ocean washes Eurasia, Africa, Australia, Antarctica.