The mystery of the strange circle on the earth

Speaking of the crop circle, everyone should be familiar with it. Since the 1970s, people began to notice the crop circles in Wales, England. Thousands of crop circles of various sizes, shapes, and complex patterns have appeared all over the world. Although many scholars have tried to explain from multiple perspectives such as soil, weather, moisture, and organisms, and some even think that this is a masterpiece of aliens or a prank made by humans, the answer has not yet been fully solved.

In addition to the crop circles, there are many interesting circles on the earth. Although they look unusual and have different causes, they are all masterpieces of nature, and behind them there are certain scientific laws hidden. Next, let us uncover their secrets together.

Rapeseed Field Circle
Although the crop circles are endless, they are rarely found in our country, but similar circles have appeared in rape fields. In July 2007, Zhaosu County in the Ili Kazakh Autonomous Prefecture of Xinjiang was holding a rape flower festival. When the photographer took a hot air balloon for aerial photography, he accidentally found a row of about 17 meters in diameter and about 2 to 3 meters apart in the rape field. Big circle. Different from foreign wheat field circles, the rape field circles show that the rapeseed inside the circle grows a lot taller than the outside circle. After the incident spread, people’s speculations arose: some people think that it was caused by farmers’ fertilization, some people think that there may be ancient ruins or tombs under the soil of the rapeseed circle, and some people think that this is purely deliberate. Later studies have found that this is all due to local sprinkler irrigation facilities: due to the excessive arrangement of sprinkler irrigation taps, the rapeseed that can be irrigated grows vigorously, thus forming the so-called “rape field vicious circle.”

A circle in a farmland in Texas, USA (Image source: google earth)

If you look at the satellite map, you will notice that there are such large circles in many desert areas. For example, in the states of Texas and Kansas in the United States, there are many large circles caused by automatic irrigation of crops. They are distributed in patches and row upon row. You do not feel any strange when you are in them. Only when you look down from a high altitude will you find these strange pattern.

Submarine Circle
One day in 2012, a Japanese photographer was diving in the waters near Amami Oshima. When he reached the ocean floor about 24 meters deep, he was surprised to find a strange circle. Although its diameter is only about 1.8 meters, its shape is very unique, with a number of grooves extending outward from the center of the circle, which are evenly spaced and radiating. They look like gears, more like mysterious “crop circles”.

Perhaps you would not have thought that this complicated and beautiful pattern was created by a pufferfish measuring only a dozen centimeters. Pufferfish, also known as pufferfish, are found in sea water and fresh water. Although the meat is delicious, there are toxins in its liver, gonads and blood. Once in danger, it will bulge into a round ball. This kind of cute little guy is not just a great “artist”, the strange circles they draw on the bottom of the sea are very useful.

Scientists have discovered that the strange behavior of the puffer fish is actually to attract the opposite sex. The male puffer has worked tirelessly to build his own love nest. It first chooses the dots, then swims on the sand, using its fins to arch the grooves little by little, and sometimes finds some shells or corals. Decoration, it takes about ten days to complete all the works. Once female puffer fish are attracted by this “mansion”, they will mate in the middle of the circle, and then lay eggs to breed the next generation. From the perspective of humans, the courtship method of pufferfish is very romantic, but there are still many mysteries to be solved in this peculiar way. For example, how does the male puffer master this complicated technique? How does the female puffer evaluate what kind of circle is the most attractive?

Fairy circle
In Namibia and Angola in southwestern Africa, there is a desert called “Namibu”, in which there are numerous circular patches of varying sizes, the small ones are about 2 meters in diameter and the large ones are up to 15 meters in diameter. The strange thing is that weeds grow around the patch, but there is no grass in the middle. How does this form?

The initial explanation is often mysterious. According to local guides, it was formed by the poisonous gas exhaled by the dragon killing the vegetation, so the locals gave it a mysterious name-fairy circle. However, some scholars believe that this is the result of termite activities. Some scholars believe that this is because certain radioactive elements in the soil caused the death of plants, or the vegetation secreted a certain toxin remaining in the soil and inhibited the growth of other plants. However, these explanations lacked convincing evidence and were quickly rejected by other scholars.

The weird circular circles appearing on the grass of the Namib Desert in Africa, also known as “fairy circles” (Image source: Wikipedia)

The latest view is that the formation of the “fairy circle” is related to the natural competition of plants. Some scientists have found that this phenomenon usually occurs on grasslands with a very dry climate and a single species. Initially, the diameter of these “fairy circles” was about 2 meters, and then gradually became larger. After 30 to 60 years, the diameter of the “fairy circle” can reach more than ten meters, and then it enters a period of decline, and vegetation begins to grow in the circle. Generally speaking, different vegetations grow together in arid environments more easily to survive, because they can “self-coordination” to maximize the use of scarce resources. The more similar the shapes of two competing species are, the more consistent their ecological needs are, and the more intense the competition. If only a single species lives on a certain piece of land, the competition will become more intense. Water is the most important resource in desert areas, and all plants are competing for water resources. Once a plant dies, more other plants will lay deep roots around it and grab the scarce water resources, thus growing more prosperous. Therefore, the “fairy circle” began to form and gradually developed. However, the explanation of this theory of plant survival and competition is not fully accepted by people. The cause of the “fairy circle” is still under debate.

Doomsday sinkhole
One day in 2014, a helicopter pilot found a huge round crater while flying over the Yamal Peninsula in northwestern Siberia. According to him, the diameter of this large pit is about 80 meters, which can easily accommodate several helicopters. After learning of this, many people went on an expedition. People who didn’t know the truth called it the “doomsday sinkhole.” Later, scientists went to the field to investigate and found that this huge crater was not as spectacular as the previous bird’s eye view. Its diameter was only 30 meters, but its depth was about 70 meters, and there was an ice lake at the bottom of the pit. A few days later, Russian herders discovered two similar large pits, one of which was 15 meters in diameter and the other was only 4 meters in diameter, which surprised the locals.

After investigating the “doomsday tiankeng”, Russian scientists found that: first, the crater is funnel-shaped, with a small mouth and bottom, almost a very regular cone; secondly, the methane content in the nearby atmosphere is much higher than that in ordinary air. The content reached 9.6%; in the end, the edge of the hole here was black, much like it was formed after being burnt violently. As a result, the scientists concluded that this was due to the excessive pressure caused by the accumulation of underground gas, which caused an explosive gush.

However, it is worth noting that there is a thick permafrost layer in Russia, and a large amount of natural gas hydrate is hidden under it. Nowadays, the phenomenon of natural gas emission is constantly occurring, indicating that the frozen soil layer here has begun to partially melt. This also proves to a certain extent that the global climate is still warming. On the other hand, if more and more methane gas is released into the atmosphere, it will further aggravate the greenhouse effect. Therefore, the emergence of Russia’s “doomsday sinkhole” is not only a geological phenomenon, but also a result of climate change. Need to attract outside attention.

Black circle
In April 2009, when the astronauts of the International Space Station looked down on the earth from the sky, they discovered that two huge black circles with a diameter of more than 4.4 kilometers appeared on the ice of Lake Baikal in Russia. In fact, this phenomenon has appeared many times in April each year, but its position changes every year. Just because of its large area, it is difficult for people to detect it at close range, and its traces can only be found through satellites.

Lake Baikal is the deepest freshwater lake with the largest water storage capacity in the world. The average water depth here is 730 meters, and the deepest point can reach 1620 meters. It has always been mysterious. When the black circle appeared on the ice surface, some people speculated that it was caused by aliens, others connected it with the legendary lake monster, and some even believed that this might be caused by volcanic activity at the bottom of the lake. But Lake Baikal has never recorded a volcanic eruption in history.

Russia’s “Doomsday Tiankeng” (Image source: Wikipedia)

The mysterious ice circle that appeared on Lake Baikal (Image source: Wikipedia)

Later, related measurement data gave some clues: the water temperature in the center of the black circle is about 0.5°C higher than other areas around the lake, and the ice thickness in the edge area of ​​the circular structure is thinner than the average winter ice thickness on Lake Baikal some. Experts therefore infer that the black circle is caused by the methane gas rising from the bottom of the lake and the vortex generated by the warm lake water. Since many surrounding rivers carry sediment into Lake Baikal, after a long period of time, the thickness of the sediments at the bottom of the lake exceeds 7000 meters (the sediments of general lakes are usually only tens to hundreds of meters thick), which means Baikal The bottom of the lake can produce more methane gas.

On June 20, 2012, when visiting Lake Baikal, several Chinese tourists witnessed a misty “mysterious circle” appearing on the lake and disappeared after about 10 minutes. Before this circle appeared, ripples appeared on the lake surface, which also confirmed that there is indeed a methane gushing phenomenon in Lake Baikal.

The Eye of the Sahara (Image source: Wikipedia)

Sahara Eye
In 1965, astronauts on the “Gemini 4” spacecraft orbiting the earth took many beautiful photos of the earth. Among them, there are photos showing a huge circle with a diameter of more than 40 kilometers in the heart of the Sahara Desert in Africa. , And one ring around the other, like a big eye looking up into space, makes people shudder. This is the famous “Saharan Eye”.

Regarding its cause, there is a lot of controversy in the academic circles: some people think that this is a crater caused by a meteorite impact, but no special minerals related to the impact of the meteorite on the earth have been found; some people think that this may be a crater, but No trace of a volcanic eruption was found; others have suggested that it may be a ring-shaped coral reef in the ancient ocean, leaving a strange ring structure after the water receded. Of course, these are the words of one family and have not been widely recognized.

At present, the view accepted by most scholars is: “Saharan Eye” is a corroded dome structure. Simply put, it is the result of the combined action of terrain uplift and erosion. At first, layers of rocks were deposited one after another. Later, the magma in the depths of the strata surged up, but did not spray out of the surface. The huge force pushed up the terrain here. The bulging rock has been weathered and eroded for a long time, and then gradually flattened, leaving the harder quartzite prominent on the surface, forming obvious concentric circles, just like cutting a boiled egg in half. We can clearly see that the circle of egg white is the same as the yolk, and the “Saharan Eye” is formed in this way.

Some people say that the circle is the most perfect figure in the world. The above-mentioned strange circles, whether they are landscapes formed by geological processes or masterpieces created by certain creatures, attract people’s attention with their most perfect shapes. The reason why they are called “strange circles” is that people admire the magical power of nature; on the other hand, they express the strong curiosity of human beings about the unknown world. It is under this curiosity that we will continue to explore and solve one mystery after another.