This island in the middle of the subterranean ocean sits like a cake in the middle of a huge plate.

And the area of this underground ocean is far wider than Yun Lei expected. Although according to the detection of scientific instruments, the area of this underground ocean is only a hundred thousand square kilometers. However, according to the cloud thunder from the space gourd, the perception of this space.

The area of this underground ocean is more than 100,000 square kilometers at all. The data detected by the instruments is not accurate at all! This vast underground ocean is worth millions of square kilometers, to say the least!

At present, the Mediterranean Sea, the deepest and largest intercontinental sea in the world, is only about 4,000 kilometers from east to west, and only more than 1,800 kilometers from north to south! The total area is only more than 2.5 million square kilometers!

This subterranean ocean is about half the size of the Mediterranean. And the depth may reach more than 2,000 meters! It is deeper than the Mediterranean!

The reason why Yunlei compares this ocean with the Mediterranean Sea is because this ocean, in ancient times, when the dinosaurs were not extinct and the ancient Chinese Border Tibetan Plateau had not yet been fully formed, it was very likely to be related to the ancient Mediterranean!

The world has changed, and the vicissitudes of life. In the blink of an eye, it is tens of millions of years of time and space.

About 280 million years ago, the distribution pattern of land and sea on Earth was completely different from today's. 280 million years ago, in the northern part of the ancient land of Gondwana and the southern part of the ancient continent of Eurasia, there was no landmass, only a huge ancient ocean - the ancient Mediterranean!

The ancient Mediterranean Sea is also known as the "Tethys Sea" by geologists. At that time, the area of the ancient Mediterranean Sea was very large, it not only covered the entire Middle East and today's Indian subcontinent, but also the Chinese mainland and Central Asia, which were almost completely immersed in the ancient Mediterranean.

About 250 million years ago, the Gondwana continent began to drift northward, and 50 million years later, 200 million years ago, the Gondwana continent collided with what is now Eurasia, and the ancient Mediterranean Sea was closed ever since.

Subsequently, the area of the ancient Mediterranean began to decrease.

According to the research of geologists, about 70 million years ago, the crust of the Tibetan Plateau in present-day China began to rise. The uplift of the earth's crust forced the ancient Mediterranean to completely break away from China. Subsequently, the area of the ancient Mediterranean Sea shrank dramatically. Six million years ago, it eventually dried up.

It wasn't until later that the earth's crust shifted and the Strait of Gibraltar cracked. It took hundreds of years for the Atlantic Ocean to return to the ancient Mediterranean Sea, which had dried up, and it took hundreds of years to fill up the ancient Mediterranean basin more than 3,000 meters below sea level. This led to the formation of what is now the Mediterranean. and become part of the Atlantic Ocean.

When Yun Lei saw the changes in this period of geological history, he felt a little strange - this huge ancient Mediterranean Sea was actually evaporated after tens of millions of years?

Even if the ancient Mediterranean became isolated from the outside world. However, the terrain is so low, there will always be a steady stream of freshwater flowing into it!

Even if more water is evaporated than is injected, it is impossible for such a huge ancient Mediterranean Sea to be evaporated cleanly! The Aral Sea, which is only 68,000 square kilometers, has existed for 5.5 million years! The ancient Mediterranean Sea, which is the size of hundreds of Aral Seas, will take hundreds of millions of years to completely evaporate even if it slowly evaporates in desert areas where precipitation is lacking!

There must be some special reason why a huge ancient Mediterranean Sea has disappeared so quickly!

This idea, Yun Lei just thought about it back then. Now, I understand that the reason why the ancient Mediterranean Sea died so quickly was not because it was located in a desert and evaporated quickly or anything. It is because when the ancient Mediterranean Sea withdrew from the place where China was located, a part of the seawater, along with some ancient creatures, was injected into this huge underground ocean and underground space.

Because there is no light in sight, there is no strong evaporation, and there is an infusion and replenishment of underground rivers, so this underground ocean, although it does not communicate with the outside world, still exists after hundreds of millions of years. And because the area is large enough, under the action of the tides and the rotation of the earth, the water flow will circulate on its own, and it will not become a pool of stagnant water.

And this huge underground ocean covers an area of millions of square kilometers, although it is very unexpected by Yun Lei. After all, the total area of China's border-Tibet plateau has reached 2.4 million square kilometers! It accounts for a quarter of China's area.

If the towering Tibetan Plateau in China is the roof, and this huge underground empty space is the house, then the ratio of the actual usable area to the construction area is not too exaggerated.

However, if this subterranean ocean is ancient, then in this ocean, this crater with continuous lava gushing, and this island, which is larger than Bowl Island, may reach or even exceed 40,000 square kilometers, is even more ancient......

According to Yun Lei's calculations, this huge island, or mountain range, should have formed and existed before the formation of this underground ocean.

Otherwise, there would be no creatures far older than dinosaurs in the huge hot spring lake next to the crater.

According to Yun Lei's communication with those terrorists and his observation of the living habits of these terrorists and their activity territory, it was found that the eight hundred active areas of the terrorists on this island were only about half of the island, that is, about 20,000 square kilometers.

This area is not only enough for the current civilization and the terrorists in the ignorant period, but also has a huge space for development. After all, it is not only the ferns that feed these dinosaurs, the remnants of primitive birds and small dinosaurs, but also the various flora and fauna of the sea.

Today, the only thing that restricts the continued development of terrorists is civilization and technology.

And the other half of this island, although there are also various creatures, but for the horror of people, it is more dangerous.

Although the eruption of this volcano was not violent, it was far worse than what Yun Lei had seen, and the volcanic eruption caused by the hand of Tamaki on Dongying Island on the surface of the earth. Not to mention that there is no large amount of toxic gases and volcanic ash spewing out like a fountain, even the heat here is limited.

The only indication of a volcano is the quietly flowing lava and the hot springs.