The theme of our review will be the Nevelsky Strait. In Russia, many people know about him. Let's clarify some details. For example, its history, in honor of whom the Nevelsky Strait is named, what is its depth, etc.
Description
Nevelsky Strait is a body of water that connects continental Eurasia and Sakhalin Island. It also connects the Tatar Strait with the Amur Estuary and borders the Sea of Japan.
During the reign of Stalin, it was planned to build a bridge over it. But the project was never implemented. Another project is the construction of a dam, which will be used as a bridge between Eurasia and Sakhalin. However, there is much debate. Some scholars suggest that due to the construction of an artificial object, the waters of the strait will become warmer, while others put forward the opposite point of view, arguing that the dam will help reduce temperature. According to the third opinion, the dam will not affect the temperature of the waters in any way; cold and warm currents may come from the nearest water bodies.
Nevelsky Strait: depth, length and width
The strait is a reservoir with a rapidly changing width, its depth at the fairway is 7.2 m. The total length is 56 km and the minimum width is 7.3 km, this place is located between Cape Lazareva on the Eurasian continent and Cape Pogibi.
The strait begins at the western part of the island, the width on this section is 80 km, and the depth is about 100 m. The reservoir is divided into two parts, one has 9 bays and the other 16. At the same time, they are observed as deep-sea areas throughout the strait, with a depth of up to 700 m, and shallow, where you can move on small boats.
In whose honor is the strait named
So in honor of whom was the Nevelsky Strait named? He was named in honor of the Russian admiral, explorer of the Far East, Gennady Ivanovich Nevelsky in 1849. The discovery of the reservoir occurred during the Amur expedition, which lasted from 1849 to 1855.
Nevelsky began naval service in 1834, commanded the Baikal transport. At this time, he went with cargo from Kronstadt around Cape Horn to Petropavlosk-Kamchatsky, explored the northern part of Sakhalin.
In the summer of 1849, the admiral went down to the mouth of the Amur River and discovered the strait that connected the mainland and the island of Sakhalin. In addition, Nevelsky was able to descend to the lower reaches of the Amur, discovered unknown territories, proved that Sakhalin is an island, not a peninsula. The conditions of the study of the territory and waters were extremely difficult. Because of the large and high waves, it was necessary to move on special boats, which were overturned by a strong wind. Emperor Nicholas I did not like this. But after the reports of the expedition were provided, Nevelsky was again sent to the Far East for a detailed study of the territory and waters.
Hydrology of the Nevelsky Strait
Through the strait there is water exchange in the Sea of Japan with adjacent bodies of water during a change in climatic conditions. In winter, under the influence of northwestern monsoon winds, surface waters come into contact with cold atmospheric air, as a result they give off heat, cool, and become covered with ice. Ice cover is observed from late January to March.
The coastline in the south of the strait is elevated, and in the north it is gentle. Therefore, a slight difference in water temperature is possible. In addition, the state of the strait is greatly influenced by winds. The average water temperature is 11 o C. In the deepest places, it can reach up to 4-10 degrees, in shallow water - up to 13-15 degrees. At a depth below 500 m, the temperature is kept at one indicator, it is 0.5-0.7 degrees.
Depending on the depth of the reservoir, two layers can be distinguished:
- Near-surface, which varies with the season.
- Deep, does not change during a change in climatic conditions.
The near-surface layer is located at a depth of up to 500 m, mainly such an area is located in the southern part of the strait. In connection with activity, vortices are formed in different seasons, which propel the current going from the Sea of Japan through the strait to other bodies of water.
In the deep layer, practically no changes and movements of water occur; therefore, the temperature regime remains at a certain parameter. Vortex formation is extremely rare, most often due to seismic activity.
The tides
In the Nevelsky Strait and the adjacent southern territory of the Amur Estuary, tides are observed. They are irregular and semidiurnal.
During the equinox, the tides become almost regular semidiurnal, however, with an increase in the declination of the moon, inequalities still appear, they reach diurnal tides up to 60 cm. Most often tropical ones are observed.
Tides are also possible at shallow depths. Their maximum size is 2.1 m. On the Amur estuary, the maximum size of the tide is 2.5 m.
Geophysical surveys
Nevelsky Strait is located on land-water, so it is necessary to use specialized equipment. Simple ship research will not work. Due to the landscape topography, electromagnetic devices will show an incorrect result. To measure geophysical parameters, a special technique was used, consisting of several rectangles of an alternating electromagnetic field and a meter.
In the course of research it was found that at a depth of more than 50 m the effect of the electromagnetic field is enhanced. It also affects the shape of the relief. Over time, hard rocks are destroyed, and also hone, form small rocky objects. When laying pipes during construction, it is necessary to use durable materials that can withstand strong pressure.
In addition, studies have shown that the relief is mainly represented by slightly salted loams. A smaller percentage located at the surface of the water is represented by clays. Heavily salted clays are located to the west of the strait.
Seismic surveys
Seismic surveys were complicated by the presence of a cold front in winter. Therefore, it was additionally necessary to punch areas covered with ice. Magnetometers were used, all results were transmitted on a digital display.
In the course of research it was found that the most active seismic zone is located in the deep layers. Closer to the surface of the water activity is less pronounced. In addition, the strength of the magnetic field changes in the parameters when moving from one relief material to another. So, in highly salted loams, seismic activity is lower than in weakly salted loams.
In the soil uncertainty zone, the seismic activity is 0. In addition, studies have shown that in slightly salted loams, a more destroyed foundation is observed than in other types.
The value of the Nevelsky Strait
The Nevelskaya Strait is the main sea route from the mainland to the island. Every day, a large number of cargo ships transport building materials and other important goods. A body of water is an essential path for the economic development of the island.
In addition, the strait is actively catching fish such as herring, halibut, navaga and flounder. In the area of the reservoir there are a total of 25 bays where merchant and cargo ships can stop.
On the rocky shores near the strait, a large number of nesting birds can be observed. It is an ideal place for their existence.