The continental shelf is the result of crustal movements or wave erosion. The upward and downward movement of the earth's crust causes the land to sink and submerge under water, forming a continental shelf; Seawater strikes the coast, creating sea erosion platforms that can also form continental shelves when submerged underwater.

In fact, the continental shelf is the extension of the coastal land of the continent under the surface of the sea to the ocean, so to speak, the continent covered by seawater. If all the water in the sea area of the continental shelf is drained and the continental shelf becomes completely land, then the appearance of the continental shelf is basically the same as that of the continent. On the continental shelf there is a delta formed by the alluvial flow of rivers into the sea. In the waters of the continental shelf, traces of land can be found everywhere.

The sediments on the continental shelf are almost exclusively sediment brought by rivers on land, while the oceans have very little composition. In addition to sediment, rivers that never stop act as conveyor belts, carrying organic matter from land to the continental shelf. And these huge amounts of organic matter are the material basis for the production of oil and gas.

After these sediments are deposited on the continental shelf, they are either subjected to geological movements or deposition over a long period of time, resulting in the formation of sedimentary layers on the continental shelf with a thickness of more than 10 kilometers. In this sedimentary layer, once a trap with the conditions for storing oil and gas is formed, then a submarine oil and gas field can be formed in almost every trap.

This truth is something that almost every geological resource surveyor understands, but it is really not easy to accurately find the oil and gas trap in the vast sea.

And even if you find an oil and gas trap, there are many aspects that you need to pay attention to when conducting surveys. For example, what is the type of trap, what is the storage of oil and gas in the trap, etc., etc., because once you get these wrong, then it is very likely that your exploration well will not be able to produce oil and gas.

This is also a very normal phenomenon. Many subsea oil and gas fields are due to a slight discrepancy in the survey methods, resulting in a good oil and gas reservoir not being discovered.

Because surveys are carried out at sea, especially reconnaissance logging. It is not as convenient and fast as on land, and it takes a very careful plan to drill a survey well at sea, because the cost of drilling a survey well on the sea is not only several times or even more than ten times higher than that on land, but the most important thing is that the geological conditions of this sea area are extremely good, otherwise only one survey well will be drilled in the same sea area.

The discovery or failure of an oil and gas reservoir. It's to see how this survey well is played.

Of course, these are the things that ordinary surveyors need to do. Before Tang Feng obtained the star core, he had followed the leader to conduct marine surveys in the North Sea waters of the United Kingdom. As a result, after more than three months of tossing and turning, three exploration wells were drilled, but only a small oil and gas reservoir was found, and there was no value for development.

That experience is still hard for Tang Feng to forget, it was a very rare mission that Tang Feng did not successfully survey after joining the explorer company.

And not only did the survey not succeed, it was bumpy in the North Sea for three months. When Tang Feng returned to the land, he felt that the earth was shaking for almost two days, and that kind of taste was definitely not something that ordinary people could bear.

Therefore, compared with land survey, marine survey is more difficult, more expensive, and less accurate, and the surveyor suffers the most!

However, these things are for the current Tang Feng. All of them no longer exist, and there is the existence of the star core, a big killer. For Tang Feng, ocean survey is an extremely comfortable process of sea travel.

Tang's itinerary was a round trip, that is, after coming out of the mouth of the Río de la Plata, following a route about 55 kilometers from the coastline all the way south to Tierra del Fuego, and then from Tierra del Fuego to the east. Follow the Scotia Ridge to South Georgia and the South Sandwich Islands and back again.

Of course, the return route is a route almost parallel to the route from which it came, this route is about 110 kilometers away from the route from which it came, and the survey radius of the fourth-level star core is less than 57 kilometers, and so on. Basically, Tang can survey this large area of continental shelf within 170 kilometers of the coastline.

This is not a small sea area, the distance from the mouth of the Río de la Plata to Tierra del Fuego is almost 2,000 kilometers, plus the nearly 1,500 kilometers to the east, this is a total length of 3,500 kilometers, and the total width of the survey is almost 170 kilometers, which is almost 600,000 square kilometers of survey area!

If you let other surveyors survey such a large area, he may not be able to complete the survey if you give him five years, but for Tang Feng, this is just a sea trip that lasts for more than ten days. It's just that because it's spring in the southern hemisphere, the temperature is still relatively cold when it comes to the area of Tierra del Fuego, so this trip is not very comfortable.

Of course, this is for Tang Feng, if it is replaced by other surveyors, this kind of travel-style ocean survey is simply a kind of luxury vacation.

As soon as the Leaves sailed out of the mouth of the Rio de la Plata, Tang Feng quietly turned on the survey function of the star core. Suddenly, with Tang Feng as the center and a radius of almost 57 kilometers, the situation under the sea immediately appeared in the star core.

After Tang Feng instructed the bears and hyenas not to disturb him, he plunged into the luxurious cabin dedicated to him, immersed his consciousness in the space, and carefully observed the situation of this famous continental shelf.

The continental shelf in the eastern part of South America is one of the finest in the world, not only is it wide, but also has a small slope and little variation in water depth, and most importantly, in the eastern part of South America, there are several world-class rivers that flow into the Atlantic Ocean. These large rivers can bring enormous amounts of organic matter to the continental shelf.

The Orinoco River, which runs through Venezuela, the Amazon, the largest river in the world, the San Francisco River in Brazil, the La Plata River, the second largest river in South America, and several rivers in southern Argentina make this continental shelf full of possibilities.

And this is indeed the case, the situation on the seabed presented on the star core, even if Tang Feng saw it, he was secretly stunned. There are too many oil and gas traps on this continental shelf, and many are frightening! Of course, most of these oil and gas traps are located in deep rock formations, which is also greatly related to the continuous injection of large amounts of fresh water by many rivers on the continental shelf on the east coast of the South American continent. (To be continued.) )