Who will explain the geological structure of syncline?

There are two strange mountains in Linzhou, Anyang, Taiji Mountain and Bingbing North Mountain. In hot summer, caves are not hot, but they produce large icicles and ice, while in cold winter, they emit hot air. In summer, the mouth of the cave freezes, and when the ice is uncovered, there will be hail the size of an egg. Why are these two mountains so strange? Is the rock on the mountain at work, or is there another secret hidden underground? Experts from the Geophysical Exploration Team of our bureau gave a correct explanation through their work-it was caused by several special geological conditions.

This cave freezes in summer and gets warm in winter.

Taiji Mountain is located in Taohua Ancient Village, Shibanyan Township, Linzhou City. At that time, Taiji Mountain was not called Taiji Mountain, because it was frozen in summer and steamed in winter, and was called Yin and Yang Mountain by the villagers.

The most obvious phenomenon of freezing and steaming is the ice cave. The ice cave is 10-20 meters deep (now it has collapsed, leaving only a part of the hole), which is completely another world. The underground is like an air conditioner, steaming out constantly, so hot that you need to take off your thick cotton-padded clothes after going in. After it snowed, other places were covered with snow, but there was no snow within a few meters near the hole.

The colder the winter in the ice cave, the more hot air there is. After the spring of the following year, with the warming of the weather, the hot air disappeared and the ice caves began to freeze, especially in June, July and August. The hotter the weather, the bigger the ice and icicles hanging upside down in the ice cave.

There was once a family who lived on the mountain. In winter, they need to take a gourd to get water at the foot of the mountain. In summer, they go directly to the ice cave to get icicles and drink them as water after melting. Villagers collect herbs or work in the mountains, and when they are thirsty, they go to the ice cave to eat icicles as ice cream.

Strong curiosity drove the local villagers to climb every corner of Yinyang Mountain and found thousands of small holes with the same phenomenon. Some of these holes are only the size of fists, but in summer they braved air conditioning and winter heating. In summer, they uncovered the stone at the mouth of the cave, and there were pieces of ice bumps hidden under it.

This abnormal phenomenon makes Yinyang Mountain a unique landscape: after the summer rainstorm, the whole mountain is foggy and spectacular, but there is no fog on the adjacent mountains; On a clear and windless day, the leaves and weeds under the trees at the foot of the mountain have been shaking, and many butterflies on the mountain dare not fly in the grass because they are easily frozen. There are birch and sumac trees that only grow in cold areas such as northeast China and Russian.

Hanjiawa Village is 10 kilometers north of Taohua Ancient Village, and the same phenomenon exists in Bingbingbei Mountain in the west of the village.

There are also small holes in the mountains behind the ice. In hot summer, chunks of ice will condense at the entrance of these holes. The villagers have never known why it is so strange here, so they have been in awe since ancient times.

How many mysteries are hidden behind the ice? What is its real answer?

Experts from Geophysical Exploration Team Uncover the Mystery of Ice Back Formation

At the end of 1994 and 10, members of the geophysical survey team of Henan Bureau of Geology and Mineral Resources came to Hanjiawa village, where they were doing geological survey to the west of Anyang in northern Henan. After hearing about this, they set up equipment on the mountain and drilled down 30 to 40 meters. They found a cave about 10 meters in diameter underground, and there was ice under it.

An engineer gave them an answer after research: the refrigeration mechanism of ice back is because the high-density gas in the deep crust rises to absorb heat after the surface density decreases, which leads to refrigeration. This is in line with the principle of refrigerator, and the ice back area is a huge natural refrigeration source. According to experts' analysis, the ice back is related to several special geological conditions, such as gas compression conditions, good gas storage conditions and gas conduction conditions.

What caused the ice to flow back? 10 years later, geophysical exploration team of Henan Bureau of Geology and Mineral Resources conducted electrical sounding survey and geological interpretation here:

This area is located in the southern section of Taihang Mountain, with an altitude of 1 1,500 m, cliffs, steep mountains and rugged jungles, and the slate Grand Canyon is adjacent to the east. The ice back is located in the ravine at the foot of the mountain. There are many places where cold air comes out from cracks in stones or small caves. Most of them are distributed in parallel from east to west, ranging in length from several meters to several hundred meters. Among them, it is found in two places that in the summer from June to August every year, ice cones grow outward in crevices or caves, or attach to stone walls or grow in crevices. After beginning of autumn, the ice gradually disappeared, but the cold air remained the same. In winter, fog comes out from the cracks in the stone, and the snow melts as soon as it falls. There is a clear spring flowing out about 100 meters to the east, which is not affected by rainy season and dry season all the year round. There is also a clear spring flowing out on the north side, and the rainy season and dry season have great influence on the flow.

There are no shrubs and trees growing near the cold air or freezing point, only grasses, of which only two unknown grasses grow vigorously, but disappear immediately after leaving the cold air area for a few meters, indicating that these two kinds of florets have low temperature specificity.

Geologically speaking, this area is located in the center of North China Platform, Shanxi Platform and Taihang Platform Arch. There is a slate anticline in the east, and the ice back is located in the west wing of the anticline. Due to the subduction and compression of the Pacific plate, the Taihang Mountain uplift belt was formed, and neotectonic movement was the main body of this area. According to the observation of the State Seismological Bureau, Taihang Mountain rises by 3 mm every year, and several non-inductive earthquakes occur every day, which shows that neotectonic movement in this area is very active.

There is no cement between the collapsed rocks near the ice back, which can be proved to be the product of modern tectonic movement. This area is located on the west side of the axis of the anticline, and an extended fault valley is formed on the terrain, with a short vertical distance. A large fault passes through the ice back, and the rock layers on both sides are horizontally staggered by 300-500 meters. The crushing bandwidth below the ice back is about 300-400 meters, and the low temperature points are all above and near the crushing zone.

Through geological and geophysical investigation, it is preliminarily considered that the cooling mechanism is that the high-density gas in the deep crust rises and absorbs heat after the surface density decreases. It conforms to the principle of refrigerator and is a natural huge refrigeration source.

Li Gang, assistant captain and deputy chief engineer of geophysical exploration team, told the reporter that this refrigeration mechanism is caused by six special geological conditions:

1. Gas compression conditions: the Pacific plate moves westward, squeezing the North China plate, forming a compressive subduction zone on the east side of Taihang Mountain, with the southern segment of Tangyin Graben and the basement depth of about 3000-4000 meters. The uplift belt on the west side is Taihang Mountain, with an altitude of 1300- 1800 meters. Taihang orogenic belt is the product of Himalayan movement. Now the Tangyin Graben continues to decline, the Taihang Mountain rises every year, and there is also a small earthquake in Linxian County, indicating that the Quaternary orogeny is still going on. There must be a huge compressive pressure under Taihang Mountain, forcing the gas in the deep crust to compress and rise.

Second, gas conduction conditions: the ice back is located on the big fault. Due to the uplift of the earth's crust, the thick and brittle quartzite in the paleoboundary layer formed tensile cracks, which were deep and formed a good gas guiding system.

3. Gas storage conditions: Guojiazhuang fault extends westward to the west of Chefogou, then enters the Lower Paleozoic stratum, and turns back near Yangjiaogou, Shanxi after 6 kilometers westward, and the Lower Cambrian shale forms a good seal.

4. Gas guiding direction: Because the strata in the west wing of slate anticline are inclined to the west, the strata near the ice back are inclined to the west or northwest with an inclination of 5- 15. Therefore, the air guide is from west to east.

Fifth, the special geographical location of the ice back: it is located near the junction of quartzite and shale above the fault, and it is the exit point of high-pressure gas rising along the fault in the deep crust.

Sixth, the influence of atmospheric pressure conditions: ice appears in June-August, and the disappearance of other seasons is likely to be related to atmospheric pressure. In summer, the air is hot, the air pressure is low, the underground updraft is fast, and the refrigeration effect is strong; In other seasons, the air pressure is high, the underground airflow speed is slow, and the refrigeration effect is weak.

On the advice of experts, the local government invested millions of yuan to dig a deep hole from here, and a miracle appeared. There is a strong wind blowing in the hole, and the whole hole is biting cold wind. As long as there is a drop of water, it will turn into ice immediately, that is, if there is a bucket of water, it will freeze overnight, and sometimes the bucket will freeze. If you use some molds, it will freeze into vivid shapes. After transformation and development, it has become a geological park tourist attraction with great scientific and appreciation value, which is the Bingbingbei tourist attraction.