Which city lies on two continents?

Istanbul, the largest city of Turkey, is in both Europe and Asia. Separated by the Bosphorous Strait, a narrow 31-km waterway that connects the Black Sea with the Sea of Marmara, one part of Istanbul lies in Europe while the other part lies in Asia. The Strait serves as a natural boundary between the continents. Two suspension bridges across the Bosphorous Strait link the two sides.

Istanbul is one of the few cities in the world to be shared by two continents. Examples of other cities that are half-European and half-Asian include the Russian cities of Orenburg and Magnitogorsk, and Atyrau, a city in western Kazakhstan. Similarly, Suez, an Egyptian city straddling the Suez Canal, belongs to both Africa and Asia. But Istanbul is by far the largest, and the only metropolis in the world to do so.

Being the only water route between the Mediterranean Sea and the Black Sea, the Bosphorus has been the site of significant settlements and cities for a long time. Of particular importance is the Golden Horn, an estuary that joins Bosphorus Strait at the immediate point where the strait meets the Sea of Marmara, and forms a large, sheltered harbour. It was here, on the European side of the Bosphorus, that the city of Byzantium (which later became Istanbul) was founded by ancient Greeks around 660 BCE.

Picture Credit : Google

Can quicksand really suck you in?

One of the disputable things that we learnt from films is our idea of the quicksand. Does it really suck us to death? Quicksand is nothing but sand saturated with water, where the friction between sand particles is reduced. It is a mushy mixture of sand and saltwater. When you step into one, it does not immediately suck you in, rather it allows you to float, as quicksand is denser than water. It is your movement arising out of panic that digs you deeper into the pit. Because the human body is not dense enough to go all the way under, you would descend up to your waist, but no further.

At rest, quicksand thickens with time, hence your legs may get strongly held by it. But it remains very sensitive to small variations in stress. If you learn how to turn it around to your advantage, you can escape its clutches.

How to escape?

Asking your friend to pull you out doesn't work. The best way is to wriggle your legs around. This creates space between the legs and the quicksand through which water can flow down to loosen up the sand. You can get out safely using this technique. But it requires a lot of patience and considerable amount of force.

Picture Credit : Google

What is a mud volcano?

A massive explosion and a towering inferno above the Caspian Sea caught international attention recently. Initially, it was thought to be an accident in one of Azerbaijan's multiple offshore oil and gas fields in the area, but investigations revealed that the blast was caused by an underwater mud volcano.

The blast took place about 10km from the Umid gas field, 75 km off the coast of the capital, Baku. The location of the fire roughly points to a mud volcano called Makarov Bank, which exploded in 1958, releasing a column of flame 500-600 metres high and 150 metres wide.

What are mud volcanoes?

Mud volcanoes are a rare type of volcano that erupt in the form of a superheated slurry of mud and water, unlike igneous volcanoes which produce lava. They are not necessarily driven by magmatic activity. Several geological processes may cause the formation of mud volcanoes. Some mud volcanoes are created hot-spring by hot- activity where large amounts of gas react with water and surrounding rocks to form boiling mud Steam from heated water deep underground forces mud through an opening or fissure in the ground Some mud volcanoes occur only in oil-field regions Under stress, methane and related hydrocarbon gases mixed with mud force their way upward and burst through to the surface, spewing mud in a cone-like shape. This mud is often hot and may have an accompanying steam cloud. The gas that builds up inside can be ignited by sparks created by fast-moving rocks and boulders beneath the surface during eruptions. This is believed to have caused the recent inferno in the Caspian Sea.

Mud volcanoes exist around the world, from Indonesia to Italy But some of the greatest concentrations of mud volcanoes on Earth exist near Azerbaijan Azerbaijan has around 400 of the roughly 1,000 known mud volcanoes on Earth, which, along with its abundance of oil and gas reserves has earned the country the nickname Land of Fire Most mud volcanoes are situated on small islands created by their eruptions, but some are hidden below the surface and form temporary peaks above the water when active The mud volcanoes in Azerbaijan are some of the biggest and most violent in the world The size of small mud volcanoes can be as high as four feet. Lusi in Indonesia is the largest mud volcano at 2300 feet El Totumo in Colombia at 50 feet high is believed to spew out mud with medicinal properties. Many people visit the volcano to lie on its mud.

Picture Credit : Google

What is a booming sand dune?

The tallest stationary dunes on Earth can also sing! Over 1,600 feet tall, the Badain Jaran Desert Dunes in China are roughly the same height as the world's tallest buildings and hold a mysterious property known as singing sands, whistling sands, or booming dunes.

This rare occasion emits a sharp, loud noise that can be maintained for more than a minute. It is believed that it is caused by an electrostatic charge that is generated as wind pulls the top layers of sand down a dune slope, producing a low pitched rumble that can reach over 105 decibels.

Booming dunes are silent in the wintertime when moisture from precipitation is retained in the dune. The burping property depends on sand grain characteristics and can be generated all year around. In the summer time when the larger dunes produce their music, the smaller dunes in the dune field remain silent. This indicates that structural properties of the dune are critical for the generation of the singing sand. Also, booming can only be generated at slopes at the angle of repose (30 degrees) on the leeward face of dune; the same sand on the shallower windward side cannot generate the music.

Picture Credit : Google

What is special about Magnetic Hill in Ladakh?

Magnetic Hill located near Leh in Ladakh is a gravity hill alleged to have magnetic properties strong enough to make cars gravitate to the top of the hill at a speed of 20 km/hour with the engines off and interfere with the transmission of passing aircrafts if they fly over it at a lower altitude! In reality, the layout of the surrounding land produces the optical illusion that a very slight downhill slope appears to be an uphill slope. A contributing factor is a completely or mostly obstructed horizon; without a horizon, judging the slope of a surface is difficult as a reliable reference is missing.

This has become a major tourist hub, everyone is fascinated that the hill makes the car look like it’s floating upward. Tourism officials have put up a sign and a marked box on the road where tourists can park their vehicles and witness their car moving at a speed of 20 km/hr. Locals say that the Indian Air Force play it safe and don’t fly around the Magnetic hill. They also say that the helicopters and aircraft flying above the magnetic hill comes within the radius of magnetic hill start to jerk. It is advised to fly at a specific speed and height above the Magnetic Hill to avoid accidents. There are hundreds of other roads and gravity hills like this around the world, in India this phenomenon can be experienced in Tulsishyam, Gujarat as well.

Picture Credit : Google