The Caspian Sea
The Caspian Sea - the largest inland mass of water - accounts for forty percent of all lacustrine waters on Earth. It is a terminal, or endorheic lake which means its waters do not reach any ocean. Due to this, minerals gather in the water because of evaporation. Endorheic lakes are normally more pollution sensitive than ocean-draining water bodies.
One reason behind the name is that the Romans found the Caspian Sea quite salty, named it so and the name stuck. Another is it was named after the Caspians because the Caspian Sea is what’s left behind by the Tethys Ocean. The Caspian Sea was landlocked because of the continents’ drifting around 5-6 million years ago. The lake sea today borders Azerbaijan, Iran, Kazakhstan, Turkmenistan and Russia.
Natural gas and oil production platforms are position along the shores of the Caspian Sea. Additionally, large numbers of sturgeon inhabit its waters, and caviar produced with the eggs is an expensive commodity. It is widely believed that around 90 percent of all world sturgeons live in the Caspian. Seven subspecies and species of sturgeon inhabit the Sea and give it the widest diversity of sturgeon.
Fresh water goes into the Caspian Sea through Ural and the Volga Rivers in the north, but the Sea continues to be somewhat salty, south and central. But why is this sea-lake so salty, not fresh at all? The reason is that the Caspian Sea is the remnant of an ancient Thetis Ocean, to be precise, its gulf the Parathetis. Some 50-60 million years ago, the Thetis Ocean connected the Pacific and the Atlantic Oceans. Because of the movement of the continental platforms, the Caspian lost its connection first with the Pacific, and then with the Atlantic Ocean, turning the gulf into an isolated water body. So the Caspian salinity is a result of its birth. But nowadays the Caspian is 3 times less salty than the World Ocean. Because of the isolation, the Parathetis’s salinity fluctuated. In dry and hot climatic phases with no or little precipitation, it would dry up to get divided into several water bodies with water more saline than the World Ocean’s water. During humid and cool climatic phases accompanied by plenty of rainfalls, these water bodies would be overflowed to again unite and become less saline. Glaciers thawing would exert great influence and decrease water salt levels in the Parathetis. An enormous amount of freshly thawed water lowered salinity, and due to this phenomenon at present, the Sea has salt levels 3 times lower than World Ocean ones.
The Caspian Sea is home to numerous islands, all near the coastline. There are no islands in the deeper regions while Ogurja Ada being the biggest island - it is 37 km long and gazelles roam freely on it. Most of the Azerbaijan islands hold significant economic and geopolitical importance because of their oil reserves. Off the Azerbaijan coast is Bulla Island, which holds immense oil reserves. Again off the Azerbaijan coast, Pirallahi Island has oil reserves but it was among the first Azerbaijan places in which oil was found, and the first Caspian Sea Island to practice sectional drilling. Nargin is a former Soviet military base and the largest Baku bay island. Ashuradeh is located on the easternmost coast of the Miankaleh peninsula, near Iranian land. It was cut from the peninsula because islanders created a water channel for irrigation, travelling and defence.
Various islands, mostly around Azerbaijan, have received extensive environmental harm because of oil production. For example, Vulf suffered severe ecological harm from the industry on neighboring islands; thankfully, Caspian seals and different species of birds are still found.