Prevailing and maximum depths of the Black Sea. Black Sea
The Black Sea is only superficially familiar to ordinary people. Everyone knows the types of fish that are caught here, and the features are familiar to many. sea coast in certain areas. But only researchers and scientists know what is hidden under the water. The Black Sea is a deep-sea basin with steep slopes.
It is a mistaken belief that in the Black Sea the bottom drops sharply down immediately from the coast. The depth of 100 meters begins mainly at a distance of 200 kilometers from the coast in the northwest of the sea, in the main part - at a distance of 10-15 kilometers, in the region of Crimea and the city of Gagra - about 1 kilometer from the coast. The bottom of the Black Sea is flat, but there are hills with gentle slopes, cracks and ledges.
The most deep place, which was recorded in the Black Sea - 2211 meters. In 1971, after a reception in Moscow, the researchers managed to visit the Yalta depression. This is one of the deepest depressions in the Black Sea. A crew of four people on the Sever-2 apparatus descended to a depth of more than 2 kilometers. The leader of the group was M.N. Diomidov, a Soviet designer of deep-sea vehicles. As a result, the aquanauts saw that life in the Black Sea exists in a narrow surface layer 100 meters from the surface. Below this mark, the researchers saw only organic remains in the light of searchlights, which made the surrounding landscape look like a winter day, descending to the seabed in the form of large flakes of snow.
Scientists managed to go down to the bottom of the Black Sea, walk a little along it and return to base in one working day. Since the Black Sea is quite young, by studying its geology one can draw certain conclusions.
For example, some hoped to decide what came first: the continental theory or the oceanic one. There are two types of structure earth's crust- continental and oceanic. No sedimentary layer was found under the continents, the basaltic layer turned out to be thicker than under the oceans, and there is also another layer - granite, located above the basalt. Under the oceans, a sedimentary layer with a thickness of 2 to 5 kilometers is formed, below which there is a basalt layer, under which there is magma.
The Black Sea partly confirms the continental theory: hidden under its waters is the earth’s crust, which is similar in structure to the ocean, however, the layer of sedimentary rock reaches 10 kilometers, the basalt plateau is much thicker than under the oceans, but at the same time less than under the continents. The granite layer was found only in the coastal zone. Some scientists are sure that the oceans were the first to form, then the primary type of the earth's crust would have been basalt, which is why basalt rocks lie shallow under the oceans. Magma came out through cracks, which became the basis for the formation of continents. The oceanic structure of the Black Sea bottom confirms that at first the entire planet was covered by continents.
The bottom of the Black Sea is covered with soils that were formed due to the destruction of the shores, deposition of organic residues and river runoff. The sea coast is covered with pebbles, gravel, sand and silts (very small particles). Sea bottom from 20 to 150 meters from the shores it is covered with silt with valves of various shells, deeper there is clay and limestone silt, and where the 200-meter and 1500-meter depths begin, dark silt lies at the bottom.
Alexander Green recalled in “Autobiographical Tale” that he learned to read by looking at geographical map, and the first word he read was “sea.”
“The sea smelled like watermelon,” we read in the story of the great master of epithets and comparisons, Ivan Bunin. But Anton Chekhov liked the simple children’s definition most of all: “The sea was big.”
In fact, is it possible to say more precisely about this “model of the universe”? As a happy moment in life, we remember the day when we first saw the Black Sea, so we are drawn to it, so in the middle of winter we count the days until our vacation. But if not us, then our children and grandchildren need to know something about the sea, besides the fact that it is “big”!
Origin of the Black Sea
The origin of the Black Sea is closely connected with the history of the entire earth. At the dawn of its history, the earth was a red-hot ball of fire. Then the earth began to cool, moisture began to condense, and heavy rains began to fall over its surface, which began to fill all the depressions and dry land. We started to gather The groundwater. This is how the world's seas and oceans were born.
Initially, sea water was not salty. But over the past millions of years, sea water has become salty. Water evaporating from sea surface, left all the salts and minerals, while being replenished with water deep rivers, which were washed away by the young rocks enriched with salts. Thus, the world's oceans filled with minerals and became salty.
Sea water contains all the elements of the periodic table known on earth. But the first place in content is occupied by sodium chloride, known as table salt, and magnesium sulfate - bitter salt. Thanks to them, sea water has a salty taste.
The Black Sea is the heir of the world ocean Tethys, the waters of which stretched from the modern Atlantic Ocean to Tikhoy. Millions of years passed before modern seas were formed and the mountains that divided it grew.
About twenty thousand years ago, the Black Sea basin was completely isolated from the World Ocean. Numerous sources of replenishment of water reserves were fresh rivers. In fact, the Black Sea at that time was a lake. Only ten thousand years later did the overflowing freshwater Black Sea reservoir connect with Sea of Marmara through the Bosphorus Strait. Ocean water, enriched with salts, rushed torrent the tsunami is actively filling it. This natural disaster described in the Old Testament and better known as the Great Flood.
IN sea depths the water is colder and saltier than in the upper layers, and therefore cannot rise to the surface to become enriched with oxygen. Where there is a lack of oxygen, hydrogen sulfide accumulates. The Black Sea at a depth below two hundred and twenty meters is saturated with hydrogen sulfide, and at the bottom there is a thick layer of black silt. Life in hydrogen sulfide layer no, with the exception of hydrogen sulfide bacteria only. Recent measurements of hydrogen sulfide levels in the Black Sea show that they have begun to rise.
During the entire period of formation of the modern appearance of the earth, the Black Sea repeatedly merged with the Mediterranean Sea and the Caspian Sea. And only about six to seven thousand years ago the Black Sea became what we see it today.
History of the name of the Black Sea
First famous name Black Sea - “Temarinda”, which means “Dark Abyss”. That's what the Taurians called him, ancient inhabitants Crimea.
The Greeks, who appeared off the coast of Crimea in the 8th century BC, called the Black Sea Pont Aksinsky - the Inhospitable Sea. For them it was a sea full of pirates, where the shores were swarming with tribes of wild aborigines. But centuries passed, enterprising Hellenes gradually settled on the Crimean shores, founded cities, developed trade, and centuries later the Black Sea was called Pont Euxine - the Hospitable Sea.
A thousand years ago the Black Sea was called the Surozh Sea. Then, through modern Sudak, and in the past Surozh, the Great Silk Road ran. It was also called the Russian Sea.
The modern name “Black Sea” was strengthened only in the Middle Ages, when tribes of nomadic Turkic peoples invaded Crimea. But it sounded different. Mare Negrum - the Genoese and Venetians called it. Karadenis - Arabs. Black sea - foreigners are now saying. But since then the name has always been the same - the Black Sea.
Currents of the Black Sea
While vacationing in Crimea, you often hear the phrase that “the tide has changed.” What kind of current is this in the Black Sea? You can conduct an experiment if somewhere in the Odessa area you let in free swimming boat, the current will carry it to the Bosphorus Strait itself.
The currents of the Black Sea are closely connected with those flowing into it large rivers- Dnieper, Danube, Southern Bug. There the water level rises significantly. Here it should be remembered that the globe rotates from east to west, and water flows into the Black Sea to the south, deflecting it to the west, directing it along the coasts of Turkey, the Caucasus, Crimea - and so on in a circle...
The width of the Black Sea Current is only sixty meters, the speed is half a meter per second. He is opposed southwest wind(it is called “squeezing”), which lifts deep cold layers of water to the surface. It is this southwest wind that causes a short-term cooling of sea water near South Bank Crimea. This phenomenon has become local residents Crimea is called “nizovka” when the sea water temperature can drop sharply from 25 to 13 degrees. But just a couple of days is enough, and the Black Sea warms up again. You can devote your free time from the sea to excursions and mountain hikes.
In the Black Sea Bosphorus Strait, two currents operate simultaneously. On the surface, the water moves from the Black Sea to Marmara. But at depth the water moves back to the Black Sea. If you throw a container of water on a cable from a boat that is being carried by the current into the Sea of Marmara, then, having dropped to a depth of about thirty meters, it will begin to move the boat along with it against the current on the surface - towards the Black Sea.
Relief of the Black Sea
The Black Sea waters connect Crimea with Turkey, Russia, Georgia, Romania, and Bulgaria. Through the Kerch Strait it is connected to the shallow Sea of Azov, and through the Bosphorus Strait - with the Sea of Marmara and then the world ocean.
The Black Sea is one of the deepest inland seas globe. The maximum depth reaches 2245 meters, while the average depth of the Black Sea is 1280 meters. The area of the Black Sea is 442 thousand square kilometers. In terms of volume of water, it is six times greater than the Caspian Sea, and sixteen times the Baltic Sea, although their areas are approximately equal in size.
Most big Island in the Black Sea - Zmeiny. It occupies an area of only 1.5 square meters. kilometer There are no other large islands in the Black Sea.
The Black Sea is inland. The ocean ebbs and flows under the influence of lunar gravity are almost imperceptible in it.
The relief of the Black Sea bottom is characterized by three forms. This is a continental shelf - a shelf, a continental slope and a deep-sea Black Sea basin.
The sandbank occupies about 24% of the entire area of the Black Sea bottom, and from the shore it descends to a depth of 100 - 140 meters. The width of the Black Sea shelf in the north-west reaches 200 - 250 kilometers, eastern shores– no more than 6 - 10 kilometers. There are places where it does not exceed 500 meters from the shore.
About ten thousand years ago, the shelf was a plain along which rivers flowed. After the melting of the glaciers, these plains were flooded by sea waters.
The continental slope off the Crimean coast is steep, reaches 30° and is considered steep. It is characterized by deep depressions, wide underwater valleys, giant underwater rocks, hills and rock faults. Sea water slides along the continental slope with high speed up to 90 km per hour and destroys the soil.
At a depth of 2000 meters, the bottom of the Black Sea basin begins, which occupies about 30% of the entire water area. The shape of the basin is perfectly flat, oval, slightly inclined to the south.
The Black Sea covers land - one centimeter per year. For example, at the very cliff of the Heraclean Peninsula stood an ancient temple, which stood at that time on safe distance from the sea. Now it is hidden in depths of the sea. According to scientists, by the end of the 21st century the level of the Black Sea will rise by 1-2 meters. This means that in the next 50 years all city beaches will go under water.
Fauna of the Black Sea
The fauna of the Black Sea is quite diverse. First of all, this different kinds commercial and non-commercial fish - sturgeon (the largest of them is beluga), Azov flounder, mullet, pelengas, Black Sea flounder, red mullet, sea bass, horse mackerel, mackerel, herring (the herring family also includes anchovy, sprat, sprat), goby, sea ruffe, greenfinch and others - about 180 species in total. From Mediterranean Sea Through the Bosporus and Dardanelles straits, tuna, swordfish, bluefish, bonito, and garfish enter the Black Sea.
Also found here black sea shark- katran, three species of dolphins - bottlenose dolphin (the largest of them, up to 3 m long and weighing up to 400 kg), white-sided and azovka (the smallest), there are two types of stingrays, jellyfish, mussels, rapana, crabs and other inhabitants of the deep sea .
The Black Sea monk seal once lived on the Crimean shores. Last time it was seen in the Novy Svet bays in 1927. But off the coast of Turkey and Bulgaria it has survived to this day.
Oysters were once found in the Black Sea, but Pacific brine, which accidentally ended up in the Black Sea with Far East about fifty years ago, practically destroyed them. It's a pity. And the red mullet got its second name - sultana - because it was considered a favorite fish Turkish sultans thanks to the subtle delicate taste. Today red mullet is served in the most sophisticated Crimean restaurants.
Very often the question arises about Black Sea jellyfish - what are they? We will answer. There are two types of jellyfish found in the Black Sea: Aurelia and Cornerot. Aurelia has a flat-shaped umbrella, 10-20 cm in diameter, along the edges of which there are numerous thread-like tentacles. Cornerot - more large jellyfish with a dome diameter of up to 40-50 cm, from which 8 large processes extend. The tentacles of jellyfish are equipped with so-called stinging cells; from touching them, a person gets a burn, like from nettles, traces of which remain on the body for up to several hours.
Due to hydrogen sulfide contamination organic world The Black Sea, although diverse, is not rich. You won't find corals here, starfish hedgehogs and lilies, cephalopods and other groups of animals that are characteristic of “ordinary”, and even more so, tropical seas.
But, like any sea, the Black Sea is shrouded in many secrets. What can you hear! Exciting stories about ancient Greek sailors and bloodthirsty Taurus pirates; romantic stories about lovers separated by sea and circumstances; legends about countless treasures stored at the bottom of the sea in sunken ships...
Length of the Black Sea from west to east - 1167 km, from north to south - 624 km. Greatest depth 2,212 m, and the average - 1,271 m. The length of the coast along the perimeter is 4,090 km, the length coastline reaches 4,340 km. The area of the Black Sea is 423,000 square meters. km.
Due to the excess inflow of fresh water from the Danube, Dniester, Dnieper rivers, Southern Bug, Mzymty, Bzybi, Kodora, Inguri and others. (more than 300 rivers) above evaporation it has less salinity than the Mediterranean Sea. Rivers contribute 346 cubic meters to the sea. km fresh water and 340 cu. km of salt water flows from the Black Sea through the Bosporus.
Depth of the Black Sea
Black Sea is one of the deepest sedimentary basins in the world. The thickness of sedimentary deposits on the seabed is 14 km. The bottom relief is a deep basin with steep slopes, its maximum depth is up to 2211 m. The area of the Black Sea is 413,488 square meters. km. Maximum length- 1148 km, maximum width - 615 km, length of the Black Sea coastline 4077 km.
The Black Sea washes the shores of Russia, Abkhazia, Georgia, Turkey, Bulgaria, and Ukraine.
There are few bays, bays and peninsulas in the Black Sea and almost no islands. This is due constant increase sea level.
Composition of Black Sea water
Salty taste Sodium chloride gives sea water, and magnesium chloride and magnesium sulfate give it a bitter taste. Water contains 60 different elements. But it is assumed that it contains all the elements found on Earth. Sea water has a number of healing properties. Water salinity is about 18%.
About 87% of the Black Sea water volume is deprived of oxygen and is contaminated with hydrogen sulfide. At a depth of over 150 m, the water contains hydrogen sulfide, and therefore the sea is devoid of living organisms great depths. The source of hydrogen sulfide is the decomposition of residues aquatic organisms, at a depth of 150-200 m, the hydrogen sulfide content reaches 7.5 cubic meters. cm per liter of water, and total it amounts to a billion tons. The uniqueness of the Black Sea is that in the deep layers of its water there are no algae, invertebrate animals and fish, there are no living creatures except sulfur bacteria.
Determined that age of the Black Sea about 8 thousand years.