Could seismic clouds really be natural "forecasters" of earthquakes, and is there any relationship between earthquakes and meteorology?
In fact, as early as the 17th century, there is a record in ancient Chinese books that "the sky is clear during the day or after sunset, and there are thin clouds like a line, very long, and the earthquake is also a sign". However, there is no rigorous scientific definition of "seismic cloud", and even the name itself is not proposed by earthquake scientists. Seismic clouds generally refer to the appearance of straw-like or band-like clouds in the sky around the area before the occurrence of some moderately strong earthquakes. Earthquake clouds appear mostly in the morning and evening, and the longer the seismic cloud lasts, the closer the corresponding epicenter, the longer the length of the seismic cloud, the closer to the time of the earthquake, and the more terrifying the color of the seismic cloud, the stronger the corresponding earthquake intensity.
The biggest characteristic of "seismic clouds" is "strange". According to meteorological observations, people roughly divide "seismic clouds" into four types: the first is a banded cloud, like the traces left by an airplane, but it is thicker and fuller, it generally indicates that the epicenter is on the vertical line of the cloud direction, the second is a wavy or radial cloud, if the cloud is radial, the intersection point of the cloud is generally perpendicular to the ground is the location of the epicenter, the third is a vertical cloud like a tornado, or like a vertical upward column of smoke when there is no wind, and the fourth is a large or clumpy cloud in the shape of a solid.
Some scholars in mainland China have proposed that seismic clouds can be generated both over the epicenter and over fault zones far away from the epicenter and with stress concentrations. When the stress is transferred far away from the epicenter due to the increase of the pre-earthquake volume, the strong stress on the fault zone causes the rock to squeeze and rub in the process of stress concentration, which increases the heat, and the underground heat flow continuously escapes from the ground through the fault zone and rises to the high altitude, forming a banded seismic cloud. Since most fault zones are perpendicular to the direction of seismic wave transmission from the epicenter, the resulting banded seismic cloud is also the direction of seismic wave transmission perpendicular to the epicenter. This idea explains why seismic clouds are found far away from the earthquake zone. However, there are still doubts that cannot be explained, such as the fact that for those distant seismic clouds that are half a world apart, it is difficult to transmit stress.
At present, the formation of seismic clouds and the relationship between them and the occurrence of earthquakes are still speculative and lack experimental evidence. Because the earthquake itself is a very complex process, there are still many mysteries to be solved.
5. According to the original text, one of the following understandings of "earthquake cloud" is incorrect:
A. Seismic clouds generally precede certain moderate to strong earthquakes, but there is no rigorous scientific definition of them.
B. Seismic clouds come in a variety of shapes, and experiments have shown that they are inextricably linked to earthquakes.
C. Seismic clouds can arise both over the epicenter and over fault zones far from the epicenter.
D. Seismic clouds are formed by the underground heat flow generated by the earth's crust in the movement of the earth's crust escaping from the ground and rising to the sky.
6. One of the following statements is not in accordance with the context:
A. Seismic clouds that are vertical like tornadoes, or vertical upwards like plumes of smoke when there is no wind, and whose intersection with the ground is the epicenter.
B. Teleseismic seismic clouds are inseparable from the strong stress action on the fault zone, but this does not explain the phenomenon of teleseismic seismic clouds that are half a world apart.
C. The idea that the banded seismic cloud is perpendicular to the direction of seismic wave transmission from the epicenter explains the phenomenon of seismic clouds being found far from the seismic zone.
D. Earthquakes are a very complex process with many mysteries to be solved, so the connection between earthquakes and seismic clouds remains speculative.
7. Based on the original information, one of the following inferences is incorrect:
A. The records of earthquake clouds in ancient Chinese books show that the ancients had some superficial understanding of earthquakes.
B. The more terrifying the color of the earthquake cloud, the stronger the corresponding earthquake intensity, and vice versa, the weaker it is.
C. Seismic clouds can be divided into four types, and according to the shape of the seismic cloud, one can determine the area where the earthquake occurred.
D. With the continuous deepening of scientists' research on seismic clouds, it is possible for people to scientifically understand seismic clouds.