What happened during the Wenchuan earthquake?

The environment could not be found, but there were some anomalies and protective measures before the earthquake.

Key words: sudden disappearance of pool water \ abnormal rain and snow \ ground collapse \ solar halo \ animal abnormality \ earthquake cloud

1.On May 5, about 80,000 cubic meters of water in Guanyintang Village, Baiguo Village, Enshi City, Hubei Province suddenly disappeared. Xiacunba Village is about 19 km away from Enshi City. The reporter saw at the scene yesterday that the pond was round, with a diameter of about 100 m and a depth of several tens of meters. The pond has dried up to the bottom, leaving black mud at the bottom. The villagers said that the surface of the pond is flush with the ground and does not dry up all the year round. The water is green, with a storage capacity of about 80,000 cubic meters. At 7 o'clock in the morning of April 26, a whirlpool suddenly appeared on the calm water, accompanied by a roar. In less than five hours, a pool of clear water disappeared and black mud appeared. A villager surnamed Chen went down to the pond alone and caught two big fish weighing more than 10, but there were not many fish in the pond.

According to the records of Yinxing Township, this phenomenon appeared three times after the national liberation, at 1949, 1976 and 1989 respectively.

2. Huaxi Daily reported in May 10 that there was a great migration of toads in Tanmu Village, Xin 'an Town, Mianzhu City, Sichuan Province, and hundreds of thousands of toads took to the road. Mianzhu is only a few tens kilometers away from Wenchuan. Mianzhu is within the earthquake center.

On May 4th, millions of toads gathered near Liu Duo Gate in Xinlou Village, Wu Jian Town, Jiangdu City, Jiangsu Province.

On May 9, tens of thousands of little toads suddenly migrated on the Dongfeng Bridge in Taizhou City, Jiangsu Province.

On May 1 1, tens of thousands of little toads migrated to Zhujing Garden, Guli Town, Changshu, Jiangsu.

3. On the evening of May 9th, the evening of May 10, and the morning and afternoon of May 1 1, it snowed four times in succession in Wutai Mountain area, and all five terraces were covered with white holy garments. Wutai Mountain is surprised to see the wonders of flying snow in May.

On the morning of April and May 10, around 10, a spectacle of solar halo appeared over the Yellow River Beach in Mengzhou, Henan Province, which lasted until around 1 1: 30. Solar halo is a rare astronomical phenomenon.

From 10 to 1 1 night in June and May, there were five uneven thunderstorms in Shijiazhuang, the capital of Hebei Province. Thunderstorms alternate with sunny days twice. At around 20: 40, the provincial capital was hit by hail from west to east.

7. Just half an hour before the earthquake, on the afternoon of May 2 1: 58 to 2: 02, a netizen "peng2283" in Tianshui City, Gansu Province captured a group of strange photos over Nanguo Temple in Tianshui City. The clouds in the sky danced like hydrogen bombs.

On Monday morning, the fish in Dujiangyan fish pond kept jumping, and many people went to catch fish.

9. At noon, it suddenly became almost as dark as night.

10. The Seismological Bureau of Nanning selected 7 snake farms in Nanning as artificial observation points, installed cameras, and conducted remote observation on the behavior habits of more than12,000 cobras for the study of impending earthquake prediction.

I think we should pay attention to the animal omen before the earthquake, because the earthquake is a devastating natural phenomenon. As the saying goes, "it's easier to go to heaven than to go to earth." Since it is difficult to go to the earth, why not use some macro-omens before earthquakes to study and predict earthquakes on the ground? Because some animals have some special functions, they can really predict earthquakes in advance, such as snakes, toads, mice and so on.

[Edit this paragraph] Safety preparation

1. Are the security measures in your house foolproof?

The usual preparation work is the basis of keeping the victims to a minimum.

Do a good job in fixing large wardrobes, sideboards, kitchens and refrigerators to prevent dumping.

Stick transparent film or adhesive tape on the glass of sideboards, kitchens, windows, etc. To prevent the glass from splashing around when it is broken.

In order to prevent the cupboard door from opening due to earthquake shaking and the contents from falling out, hinges are installed on the cupboard door and closet door to fix it.

Don't put TV sets, vases, etc. In a higher place.

In order to prevent the glass fragments scattered on the ground from hurting people, thick slippers are usually prepared.

Pay attention to the placement of furniture to ensure a safe space.

Pay full attention to the management and storage of fire-fighting appliances and dangerous goods such as kerosene heaters.

Strengthen the cement precast slab wall to make it strong and not easy to collapse.

2. Are the emergency supplies ready?

(1) drinking water (2) food, baby milk powder (3) first-aid medicine (4) portable radio, flashlight, dry battery (5) cash, valuables (6) underwear, towels, toilet paper, etc.

3. From peacetime, establish a cooperative system of neighborhood mutual assistance.

When a big earthquake happens, it can be expected that it will cause great disasters on a large scale. In this case, it is impossible for fire engines and ambulances to be on call. Therefore, it is necessary to communicate with local residents through streets and other organizations in peacetime, and establish a system of mutual assistance and cooperation to deal with fires and wounded people.

Generally speaking, once something happens, neighbors should discuss the system of mutual assistance and cooperation.

Actively participate in civil disaster prevention organizations.

Actively participate in disaster prevention training.

[Edit this paragraph] Emergency preparedness for impending earthquake

In areas where the imminent prediction of destructive earthquakes has been released, the following emergency work should be done:

1. Prepare emergency items in case of earthquake. After the earthquake, the production and supply of food, medicine and other necessities will be affected. Water towers and water pipes are often damaged by earthquakes, resulting in the interruption of water supply. In order to overcome the initial difficulties after the earthquake, society and families should prepare a certain amount of food, water and daily necessities before the earthquake to solve the urgent needs.

2. It is also an important issue to build a shelter for the coming earthquake. The house was damaged by the earthquake and needed a place to live; Aftershocks keep coming, so there should be a hiding place. Therefore, it is necessary to temporarily build a shockproof shed that is shockproof, fireproof, cold-proof and rain-proof. All kinds of tents can be used, and the small round barn for storing grain in rural areas is also a good earthquake-resistant house.

3. Delineate evacuation places and transport dangerous goods: the city is densely populated, and it is difficult for people to evacuate from the earthquake. In order to ensure the safety of people during the earthquake, people should be allocated according to streets and districts before the earthquake, and evacuation routes and places nearby should be delineated. Before the earthquake, inflammable, explosive and toxic substances should be transported to the city for storage in time.

4. Set up an emergency center for the wounded in a place with strong earthquake resistance in the city, or set up an emergency center outside the city, and prepare beds, medical equipment, lighting equipment and medicines.

5. Suspension of public activities After receiving the official notice of the impending earthquake prediction, all kinds of public places should suspend their activities and the audience or customers should evacuate in an orderly manner; Primary and secondary schools can temporarily attend classes outdoors; The station pier can wait in the open air.

6. Organize personnel to evacuate and transfer important property. If you get a formal warning or notice of impending earthquake, you should quickly and orderly mobilize and organize the masses to evacuate the house. Seriously ill patients who are being treated should be moved to a safe place. For a few people with mental paralysis, they should also be mobilized to safety. Large livestock, tractors and other means of production in rural areas should be properly transferred to safety before the earthquake, and vehicles of government agencies, enterprises and institutions should leave the garage and park in an open place in order to play a role in earthquake relief.

7. Prevent the occurrence of secondary disasters. Serious secondary disasters may occur when earthquakes occur in cities, especially in chemical plants, gas plants and other units prone to earthquake secondary disasters. It is necessary to strengthen the assessment management and assign special personnel to stand guard and be on duty day and night.

8. Ensure the security of confidential departments. There are many confidential departments and banks in the city. During the earthquake, security precautions should be strengthened to prevent the loss of state-owned assets and the disclosure of secrets. The vehicles of the fire brigade must be out of the warehouse, and the firemen should be ready to go, so as to put out the fire in time and reduce economic losses.

9. Organize rescue teams and arrange production reasonably. Before the earthquake, governments at all levels should organize rescue and relief teams (rescue, medical care, fire protection, water supply, power supply, communication, etc.). ) On the spot. When necessary, some factories should suspend production or run at low load under the unified instruction of the earthquake prevention headquarters.

10. Be prepared for earthquake prevention at home. Residents in areas where earthquake prediction has been issued must make good preparations for earthquake prevention at home, make a good plan for earthquake prevention at home, and promptly investigate and eliminate hidden dangers that are not conducive to earthquake prevention at home. (1) Inspection and reinforcement of houses. Buildings that are not conducive to earthquake resistance should be reinforced, and dangerous buildings that are not suitable for reinforcement should be evacuated. Heavy house decorations, such as parapets and high doors, should be removed. ⑵ Place furniture and articles reasonably, fix tall furniture to prevent people from dumping, and take shelter under solid furniture during the earthquake; Furniture items should be placed "above the bottom", and the hanging objects on the wall should be taken down and put in a fixed position to prevent people from falling; Clean up the sundries and keep the doorway and corridor clear; Balcony parapet should be cleaned, flowerpots and sundries should be removed; Flammable, explosive and toxic substances should be placed in a safe place; (3) Prepare necessary shockproof articles. Prepare a family shockproof bag, including food, water, emergency lights, simple medicines, ropes, radios, etc. , and put it anywhere for easy access. (4) Conduct family earthquake drills, emergency evacuation drills and "one-minute emergency avoidance" drills.

1, groundwater anomaly

Groundwater includes well water, spring water, etc. The main anomalies are turbidity, bubbling, flowering, temperature rise, discoloration, odor change, sudden rise, sudden drop, borehole deformation, sudden exhaustion or spewing of spring water, etc. People summed up the proverbs of well water changes before the earthquake:

Well water is a treasure, and earthquakes have precursors.

When it doesn't rain, the spring water is turbid, and when it dries, well water emerges.

The water level rises and falls, and flowers are bubbling.

Some change color, some change taste.

2. Biological abnormality

Some organs of many animals are particularly sensitive. They can know some disasters ahead of humans, such as jellyfish in the ocean can predict storms, mice can avoid mine disasters or harmful gases in advance, and so on. As for the organs of vision, hearing, touch, vibration and balance, which plays the main role and which plays the role of assisting judgment may be different for different animals. Physical and chemical changes (vibration, electricity, magnetism, meteorology, abnormal radon content in water, etc.). ) The accompanying earthquake can often stimulate some sensory organs of some animals and cause abnormal reactions. If the gravity of an area changes, some animals may be able to feel it through its balance organs; Some animals' hearing organs may be able to detect abnormal vibrations. Before the earthquake, the underground strata have been moving slowly day by day, showing a creeping state, and there is strong friction between fault planes, so some people think that there will be low-frequency sound waves on the friction fault planes, only a few to ten times per second, which is lower than human hearing. People need more than 20 sound waves per second to feel it, but animals don't. Very sensitive animals will be frightened when they feel this sound wave, resulting in abnormal phenomena such as winter snakes coming out of holes, fish jumping out of the water, pigs and cows jumping in circles, dogs barking and wolves growling. There are many kinds of animal anomalies, including large livestock, poultry, cave animals, hibernating animals, fish and so on. The abnormal situation of animals, people also have a few words to sum up well:

Animals have signs before earthquakes, so it is very important to prevent and treat them by groups.

Cattle, sheep, mules and horses don't enter the stables, and pigs don't eat dogs and bite people.

Ducks don't go into the water and make noise on the shore, but chickens fly up the tree and scream loudly.

The snake came out of the hole in the ice and snow, and the mouse ran with the mouse in its mouth.

The rabbit jumped and bumped, and the fish jumped into the water.

Bees are moving noisily, but pigeons are too scared to fly back to their nests.

Every household observes and reports any abnormality.

In addition, some plants also had abnormal reactions before the earthquake, such as germination, flowering, fruiting or large-scale withering, abnormal exuberance and so on.

3. Meteorological anomalies

People often describe earthquake prediction scientists and technicians as "managing the sky, the ground and the hollow", which is indeed reasonable. Before the earthquake, the weather often appeared abnormal. There are mainly sultry before the earthquake, anxiety and irritability, long drought without rain or heavy rain, yellow fog, dark sunshine, strange wind, hail in June and so on.

4. Abnormal ground sound

Geosound anomaly refers to the sound emitted underground before the earthquake. Its sound is as changeable as cannon and thunder, like the driving of heavy vehicles and the surge of strong winds. When an earthquake occurs, longitudinal waves radiate from the source and propagate along the ground, making the air vibrate and sound. Because of the high speed but weak potential of longitudinal wave, people only smell its sound, but don't feel it unconsciously until the arrival of shear wave. Therefore, there is often a record in the epicenter that "before every earthquake, the underground sound expands like gas, like boiling water in a tripod". If you are in the epicenter, you can often hear the sound of a magnitude 3 earthquake. Geosound is the result of the structure and structure of underground rocks and the movement of liquid and gas contained in them, and a considerable part of it is a sign of impending earthquake. Mastering the knowledge of geosound may have a good effect on earthquake prediction and prevention.

5, abnormal grounding light

Geophysical anomalies refer to the light emitted underground before the earthquake, which has various colors, such as silver blue, white purple, etc., which are rare in daily life, but mainly red and white; Its forms are also different, such as ribbon, sphere, column, diffusion and so on. Generally speaking, the earth's light appears in a wide range, mostly within a few hours to a few minutes before the earthquake and lasts for a few seconds. In China, colorful luminous phenomena appeared during and before the Haicheng, Longling, Tangshan and Songpan earthquakes. Terrestrial light is often accompanied by natural phenomena such as earthquakes, landslides, landslides, collapses, sand blasting, water spraying and air jetting, and often moves regularly along a fault zone or an area, and is synchronized with other macro and micro anomalies, and its causes are always closely related to crustal movement. And influenced by geological conditions, surface and atmosphere? Tired? Even hissing? Participate in the yellow? Tan Kenai: α?

At present, all the geomagnetic anomaly reports we have are from a few seconds before the earthquake to 1 minute. Such as Haicheng earthquake, Lancang earthquake and Gengma earthquake, similar reports have been collected.

6. Abnormal ground gas

Geo-atmospheric anomaly refers to the fog generated underground before the earthquake, also known as geo-aerosol or geo-fog. This kind of fog, with white, black and yellow colors, sometimes colorless, often appears in the days to minutes before the earthquake, often accompanied by strange smell, sometimes accompanied by noise or high temperature.

7. Abnormal ground movement

Abnormal ground motion refers to the ground shaking before the earthquake. It is a well-known phenomenon that the ground vibrates violently during an earthquake. But before the earthquake, sometimes I feel the ground shaking. This kind of shaking is different from an earthquake, and it swings very slowly. Seismographs often can't record it, but many people can feel it. The most obvious ground motion anomaly occurred before the Haicheng earthquake of magnitude 7.3 on February 4th, 1975. From the end of February to the end of June, there were 65438+ anomalies in Dandong, Kuandian, Fengcheng, Shenyang and Xiuyan.

8. Abnormal grounding drum

The ground uplift anomaly refers to the uplift on the ground before the earthquake. 1973 About half a year before the magnitude 7.9 earthquake in Luhuo, Sichuan, a drum appeared on a lawn in Tuoba District, Ganzi County. It was shaped like an inverted iron pot, about 20 cm high, and cracks appeared intermittently around it. The swelling disappeared after a few days, and it was repeated many times until the earthquake occurred.

Anomalies similar to ground heave include ground fissures and subsidence.

9. Electromagnetic anomalies

Electromagnetic anomalies refer to the anomalies of household appliances such as radios, televisions and fluorescent lamps before the earthquake. The most common electromagnetic anomaly is radio failure, and fluorescent lamps were also common before the North China earthquake. 1a few days before the Tangshan earthquake of magnitude 7.8 on July 28, 976, many radios in Tangshan and its surrounding areas broke down, with loud and small sounds, inaccurate frequency modulation and sometimes continuous noise. Also before the Tangshan earthquake, some people in the city saw fluorescent lamps turn red first and then light up at night. Some people in Beijing turn off the fluorescent lamp before going to bed, but the light is still on.

Electromagnetic anomalies also include abnormal operation of some motor equipment, such as abnormal microwave stations, interference from wireless power plants, and failure of electronic alarm clocks.

Macroscopic anomalies of earthquakes play an important role in earthquake prediction, especially in short-term and imminent prediction. Before the 1975 Haicheng M = 7.3 earthquake and the 1976 Songpan and Pingwu M = 7.2 earthquakes, seismologists and the general public had observed a large number of macroscopic anomalies, which provided important information for the successful prediction of these two earthquakes. However, it should also be noted that the above macro phenomena may be caused by various reasons, not all of which are signs of earthquakes. For example, the fluctuation of well water and spring water may be related to rainfall, and may also be affected by nearby pumping, drainage and construction. The discoloration of well water may be caused by pollution, and the abnormal behavior of animals may be related to weather changes, diseases, estrus and external stimuli. Also be careful not to mistake welding arc light and lightning for earth light, thunder for earth sound, and fireworks and flares for underground fireballs.

Once you find an abnormal natural phenomenon, don't easily draw the conclusion that an earthquake is about to happen, let alone panic. Instead, it is necessary to find out the time, place and relevant situation of abnormal phenomena, protect the site, report to the government or the earthquake department, and let the professionals in the earthquake department investigate and verify to find out the truth.

(2) Microscopic anomalies of earthquakes

The seismic anomalies that can't be detected by human senses and can only be measured by special instruments are called microscopic anomalies of earthquakes, which mainly include the following categories:

Abnormal seismic activity: there is a certain relationship between large and small earthquakes. Although there are not many major earthquakes, there are many small and medium-sized earthquakes. Study the characteristics of moderate and small earthquakes. It is possible to help people predict the occurrence of future major earthquakes.

Abnormal topographic changes: Before the earthquake, the crust near the epicenter may be slightly deformed, and the rocks on both sides of some faults may be slightly displaced. With the help of precision instruments, this very weak change can be detected, and analyzing these data can help people predict the occurrence of future major earthquakes.

Geophysical changes: In the process of earthquake preparation, some changes may occur in the physical properties of rocks around the source area. Using precision instruments to measure the changes of gravity, geoelectricity and geomagnetism in different areas can also help people predict earthquakes.

Changes of underground fluids: Groundwater (well water, spring water, water contained in underground rock formations), oil and natural gas, and other gases may be generated and stored in underground rock formations, all of which are underground fluids. Using instruments to measure the chemical composition and some physical quantities of underground fluid and study their changes can help people predict earthquakes.