In daily life, we usually see prepared briquettes, but it is difficult to see the original coal seam. Therefore, many people have been in a state of little knowledge about the production of coal and can't tell the source of coal. How did that coal come into being? Is there a coal seam with a thickness exceeding 100 m?
Before exploring the appearance of coal seam, let's take a look at coal mining. In fact, coal was discovered much earlier than its use. As early as more than 7,200 years ago, the remains of coal were found on the crescent site, making China the first country to use coal in the world.
Due to the lack of scientific knowledge, low productivity and advanced coal exploration equipment and means, the discovery of coal is often a pleasant surprise. In ancient times, people could only see the coal resources exposed on the earth's surface. Only when coal was exposed on the earth's surface could they find it and trigger local coal mining activities.
Through the increasingly close contact with coal, people gradually realize the importance of coal to life. Sometimes people consciously want to find such mineral resources, and occasionally there may be clues to find their existence space. These behaviors are not uncommon in China's vast territory, and such situations are often described in detail in local chronicles and historical books.
As a big coal province-Taiyuan, Shanxi, there are many records about the discovery of coal. It is said that in Xishan mining area of Taiyuan, Shanxi, there was once a child herding sheep on a hillside, and the child drove the sheep to eat grass. Because he was young and playful, one day he suddenly found that stones were on fire in some places, which interested the child and aroused his curiosity.
In order to find out why this stone can catch fire, the child took this combustible stone home and wanted to observe it carefully.
With the in-depth observation, the children found that these burning stones can help their mothers cook and bring warmth to their own fires in the cold winter. In this way, with the frequent behavior of children picking stones and the spread of burning stones, more and more adults have joined related industries, and coal has gradually been recognized and used by local people.
In fact, in the mid-1950s and mid-1970s, coal was widely exploited and used in our lives. Although the mining technology at that time was not mature, it did not prevent coal from becoming more and more prominent in people's minds.
During the Western Han, Wei, Jin, Southern and Northern Dynasties, China's coal production technology began to mature gradually, and a certain scale of coal mines appeared, which was equivalent to the current coal mines. At this time, coal resources began to be exploited in large quantities. Coal is not only used as fuel for people's daily life, but also used in smelting industry.
Workers use superb technology to make coal into pulverized coal and briquette, which makes coal contact with air more fully and greatly improves the use value of coal. With the gradual development of coal technology for thousands of years, China's mining technology has also made great progress, forming coal science and technology with ancient characteristics of China. /kloc-Before the 7th century, China's coal mining technology was in the leading position in the world.
It's hard to imagine what kind of scene it would be if we didn't see all the resources disappear one day and coal would never be used in our lives again. Now coal has become an indispensable resource in our life.
With the development of science and technology, natural wind energy and water energy have been used in global power supply technology, but the main fuel is still coal. Nowadays, people still burn coal to keep warm in winter. In addition, coal is an important raw material for metallurgical and chemical industries. It also has a great influence on modern industry, whether it is heavy industry, light industry or energy industry.
As one of the countries with the richest coal resources in the world, China's coal resources are not only large in reserves, but also widely distributed, with complete coal types and excellent quality. Therefore, at present, more than 65% of China's energy consumption is coal resources, and China generally needs to consume 65.438+0.2 billion tons of coal every year. The development and utilization of coal resources play an important role in our life.
Because of its function, coal is also called black gold, which promotes the development of local industry and national economy. As a basic energy and an important industrial raw material, coal has effectively safeguarded the security of the national economy. According to the survey, we can know the contribution rate of coal to China's GDP. There is a strong correlation.
This is mainly because China's energy structure is dominated by coal, and coal consumption is huge in the process of economic development, which leads to strong dependence on economy and coal. Therefore, during the rising period of the national economic situation, the coal industry also showed a prosperous trend.
Although the important position of coal has been gradually replaced by oil, for a long time, due to the exhaustion of oil, coal will return to its peak, and with the rapid development of science and technology, the new technology of coal planning is becoming more and more mature, and coal will surely become one of the irreplaceable energy sources in human life and production.
The coal called black gold is so mysterious that if we want to explore its origin, we can slice it and put it under a microscope. Through this observation, we can clearly see the plant tissue and structure in coal. Sometimes there are some things like tree trunks in coal seams, and some coal seams are still wrapped with complete insect fossils. From here, we can understand that the formation of coal can not be separated from plants.
Coal is a solid combustible mineral, which was buried underground by ancient plants and experienced complex biochemical and physical-chemical changes. This biochemical and physical chemical process is extremely long.
Coal is an extremely thick layer of black humus accumulated on the ground by branches, leaves and roots of plants for millions of years. Because our earth is in the process of constant change, it is constantly buried underground with the change of the crust. This layer of black humus has been isolated from the air for a long time. Under the action of high temperature and high pressure, through a series of complicated physical and chemical changes and other factors, black combustible sedimentary rocks were formed.
Therefore, the thickness of coal seam in coal mine is closely related to the regional crustal decline and the number of plants. The faster the earth's crust descends, the thicker the accumulation of plant debris and the thicker the accumulation of coal seams in coal mines.
Due to the crustal tectonic movement, the original horizontal coal seams were folded and fractured, some coal seams were buried deeper underground, some were pushed out of the surface, and even exposed to the ground and found.
From the above knowledge, we can know that coal comes from ancient earth plants. With the passage of time and the arrival of disasters, these plants gradually died of old age, and through the decomposition of microorganisms and the movement of the crust, coal seams were gradually formed. This process takes a long time, and the appearance of thick coal seams takes a long time and plant debris.
Although coal is widely distributed on the earth at present, coal seams with a thickness of more than 8 meters according to regulations can be called extra-thick coal seams. Although the coal seams in some areas are more than 8 meters thick, they are very few. Because the formation of thick coal seams requires a lot of plant debris, in this case, does a coal seam with a thickness of more than 100 meters really exist? How many plants do you need?
There are indeed coal seams with a thickness of more than 100 m in this world, so are these coal seams formed like other coal seams? The formation of extra-thick coal seams depends more on favorable sedimentary structures, and adequate water resources, lush plants and stable crustal subsidence are also essential conditions.
Lush plants provide a material basis for the appearance of extra-thick coal seams. As long as there are enough plant residues, microorganisms can continuously decompose and form coal or sapropelic structures containing carbon, hydrogen, oxygen and nitrogen. Stable crustal subsidence can provide power for the formation of extra-thick coal seams.
In the coalification stage, the subsidence of the earth's crust is needed to cooperate. Only when the temperature and pressure brought by the subsidence of the earth's crust act on animal remains, can the previously formed sapropelic structures such as hydrogen, oxygen, nitrogen and carbon and the elements such as hydrogen, oxygen and nitrogen in coal be continuously reduced, and the carbon element is retained, so that the carbon content per unit volume is gradually increased, and better quality lignite is formed to a certain extent.
Even after such a long change, the coal formed at this time needs constant tempering. On this basis, the crust needs to continue to move, and the temperature and pressure of coal will increase day by day, which will lead to the continuous reduction of hydrogen, oxygen, carbon and other elements, thus gradually increasing the carbon content in coal.
As this process continues, the density and hardness of coal will increase with the increase of pressure, and the color will gradually become darker, forming better quality bituminous coal or anthracite.
However, sufficient low-flow water can greatly ensure the quality of coal, and insufficient fluidity of water will make little debris deposition in sediments. In this case, the coal seam sediments are basically from plants. With the growth of plants from generation to generation, they are deposited and aged at a steady rate. 1 generation plants are buried by the bones of the second generation plants, which are decomposed by microorganisms in layers.
It is not difficult to see from this process that the formation of coal seam needs a lot of plant debris. So, were there so many plants on the ancient earth to supply 100 meters of coal seams?
That's for sure. As early as ancient times, the plant content on the earth is extremely rich, which can be divided into three important coal-forming periods. The 1 period is Paleozoic Carboniferous, and the coal-forming plants are mainly spores, mainly divided into bituminous coal and anthracite. The second stage is Mesozoic Cretaceous, and the coal-forming plants are gymnosperms, mainly producing lignite and bituminous coal; The third period is the third period of the Cenozoic era. The coal-forming plants are angiosperms, lignite is the most abundant and bituminous coal is the least.
Unlike other planets, the earth has many habitable conditions. The atmosphere, hydrosphere and mine circle on the earth are all formed under these suitable conditions. With the excellent environment of the earth, many life appeared on the earth in ancient times, including plants, animals and microorganisms.
According to incomplete statistics, there were about 500 million to 654.38+billion species of creatures that once existed on the earth during geological period. Although after the long evolution of the earth and the law of the jungle, most of them have become extinct. But the wind left traces, and these creatures also left indelible marks on the earth.
Their remains are often accompanied by the evolution of the earth, the subsidence, weathering and erosion of running water, and constantly undergo physical or chemical changes. Under the action of microorganisms, it becomes the natural raw material of sapropelic structure or coal resources.
Under the burial of layered plant debris and the long-term storage of nature, it eventually accumulates into a coal seam with a thickness of more than 100 meters.