Can Earthquakes Be Predicted?
ON JULY 28, 1976, the worst natural disaster of recent centuries struck the city of Tangshan, in mainland China. In minutes all but four of the city’s hundreds of multistory brick buildings were damaged, many collapsing completely on the sleeping inhabitants. Trains were derailed, highway bridges crumbled, water and electricity were cut off and 10,000 miners were trapped underground. When official casualty figures were issued three years later, 242,000 people were known to have died, with 164,000 others seriously injured.
“The seismological department had not given any warning,” admitted Chinese officials. Indeed, the massive quake at Tangshan took everyone by surprise, since a major earthquake in the area was not considered likely.
Ironically, this tragedy befell China only a year after a successful earthquake prediction there had saved thousands of lives. On that earlier occasion Chinese officials showed outdoor movies to keep the people of the Haich’ing area outside on cold February nights until the predicted earthquake arrived, right on schedule.
As a result of the Haich’ing prediction, enthusiastic press reports gave the impression that earthquake forecasting would soon be as routine as weather forecasting. The Tangshan disaster, however, indicated otherwise. For the present, the answer to the question, “Can scientists predict earthquakes?” is, “Sometimes.”
What Causes Earthquakes?
Earthquake predictions are based on various theories as to causes, and the predictions vary in accuracy. Just as there are spectacular earthquakes that arrive without predictions, there are also spectacular predictions that are not fulfilled. In 1976 an American geophysicist, Dr. Brian Brady, began predicting a massive earthquake for Lima, Peru. Later he narrowed down the date of the disaster to around August 1981. Never before had a scientist dared to predict so far in advance the exact location, time and magnitude of an earthquake. Dr. Brady’s prediction was not intended for the public, but such news is hard to keep secret, and when it got out it caused considerable consternation in the Peruvian capital. In July Dr. Brady withdrew his prediction, and the August date came and went with no earthquake.
Meanwhile, what has been going on underground? No one is sure. Most scientists believe that earthquakes occur when pressures build up within the earth, finally causing massive layers of rock to snap like a pencil being bent to the breaking point. Sometimes the pressures appear to be caused by massive continent-carrying “tectonic plates,” which grind into, over, and under one another. The famous San Andreas fault in southern California is at the boundary of two such plates. At other times, however, earthquakes can occur deep within a plate for reasons not well understood, as when massive earthquakes changed the course of the Mississippi River in the central United States back in 1811.
Scientists can often tell when pressures are building up underground, but that does not suffice for a prediction. How hard are the rocks in a given area? How much stress can they take before they snap? Will they release the stress in a series of little breaks or in one cataclysmic crash? Dr. Brady’s prediction for Peru was based on his theories of how rocks break, but such theories clearly need more work.
With or without predictions, there will almost certainly be more serious earthquakes in places like Peru, where pressures on underground rocks are unrelenting. But that knowledge by itself is not very helpful. People want to know when, and where, and how serious the next earthquake will be. Can you blame them?
From Laser Beams to Catfish
Although unexpected, the Tangshan disaster was not totally unannounced. For fourteen months beforehand an observatory in the area “recorded increasingly ominous movements along the earth fault that it straddled,” according to a report in The New York Times. “Yet, for lack of other premonitory signs, no warning was issued.” By contrast, the Haich’ing earthquake was preceded by a wide variety of warning signals, including strange animal behavior, which the Chinese take seriously in forecasting earthquakes. Finally, before the Haich’ing earthquake a number of small shocks occurred in the previous December and again just days before the earthquake. It was the ominous stopping of these foreshocks that convinced officials on February 4 that a major quake was due within hours.
Sadly, many earthquakes conform to the rule that it is always easier to identify warning signs after calamity has struck. But to be practical, only those unusual quakes that give abundant and dramatic warning signs are likely to be predicted successfully. “The problem is that no two quakes are preceded by exactly the same set of warnings,” notes one writer, “and even these symptoms can be misleading.”
As a result, a dizzying variety of possible earthquake clues is being investigated here and there around the world. Here are some of them:
Animal behavior: Tales of leaping catfish before earthquakes are so common that it was once thought that “earthquakes were caused by their thrashing about in underground streams,” reports Science Digest. The Japanese have been running tests on ten Tokyo catfish and report that they “acted abnormally before 85 percent of the earthquakes large enough to be felt by humans in a seven-month experiment.” Are the fish disturbed by very low-frequency “groans” or high-frequency “shrieks” given off by tortured rocks before they break far underground? Perhaps. Other animals that are reported to act strangely before earthquakes include snakes, rats, geese, pigs, cows and dogs, all of which were observed to act up before the Haich’ing earthquake.
Terrain changes: This method of earthquake prediction seems more “scientific” than watching animals, in that it involves numerous sophisticated gadgets, such as laser beams to record changes in the level of the land, and tiltmeters to detect the slightest change in the local slope. Other devices study local magnetic and gravitational fields. If land is rising or sinking or tilting, scientists have clues as to what might be going on far beneath the surface, down where earthquakes generally occur. The fancy hardware does not automatically mean better earthquake prediction, however. For years scientists have been watching the ground rise and fall in the area of Palmdale, California. They are still not sure what it all means.
Well-water changes: When the water flow from an artesian well in central Asia slowed dramatically, Soviet scientists predicted that an earthquake was coming. Six hours later the well dried up altogether and a large quake hit. Another very popular technique is the measuring of radon gas in well water. The gas comes from radium atoms that have escaped from rocks beneath the surface. If the rocks are about to shatter from accumulated strain, they first develop tiny cracks. Water can seep into these and absorb radon.
Problems of Partial Knowledge
Despite all the promising new methods and advances, however, earthquake forecasting is still a long way from weather forecasting. “My own opinion is that it’s going to be at least 10 years before predictions can be made with sufficient reliability and consistency to be of great use to the public,” says US geologist Clarence Allen. With the stakes so high in disasters such as earthquakes, many scientists are alarmed by the responsibility placed on them and the imperfect state of their art.
Some of these scientists are afraid that someday “they will look down at a set of measurements and their experience and intuition will tell them that a major earthquake may be imminent. But they will not sound a warning that could save thousands of lives,” notes The New York Times. Why not? “They will not have enough confidence in the evidence before them to justify predicting an earthquake to a nation where a wrong prediction could bring them professional scorn, public ridicule and possibly hundreds of lawsuits.”
The earthquake predictors are in a no-win situation. If a predicted quake does not occur, the false alarm could undermine public confidence and cause a later warning to go tragically unheeded. Real-estate values could be depressed and land developers might even sue the scientists. On the other hand, if a prediction is withheld and a quake occurs, then victims and their families could sue for negligence.
The problem here goes beyond man’s imperfect knowledge of earthquakes. It is the basic problem of priorities in a greedy society that often seems willing to risk lives rather than local economies.
The Most Accurate Earthquake Prediction
Interestingly, the man who was the most accurate predictor of earthquakes is not known as a geologist. Yet some 1,900 years in advance he predicted that a particular generation would see “nation . . . rise against nation and kingdom against kingdom, and . . . food shortages and earthquakes in one place after another.” (Matthew 24:7, 34) That forecaster of events, Jesus Christ, then went on to say that true Christians would be hotly persecuted at that time, that lawlessness would abound and love would cool off, and that the ‘good news of God’s kingdom’ would be preached all over the world, providing hope in the gathering world darkness.—Mt 24 Verses 9-14.
While various features of Jesus’ prophecy may have appeared to be fulfilled at different times in the past, outstandingly all the facets of Jesus’ prophecy have come to pass at the same time in the twentieth century starting with 1914, the year World War I began. An estimated ninety million people or more have been slaughtered in wars in our century, and the world health experts estimate that fifty million die of hunger yearly. Persecution of true Christians in fanatically nationalistic states is well documented. Increasing lawlessness is bemoaned in nearly all countries of the world.
And earthquakes? Very significantly, our century has seen more earthquake destruction than any other. From the time Jesus gave his prophecy until 1914, history records five earthquakes that each took 100,000 lives or more. In the period since 1914 at least four more such superearthquakes have occurred—in China in 1920, in Tokyo in 1923, in China in 1927, and, of course, the Tangshan quake in 1976. Truly, this generation has experienced not just earthquakes but “great earthquakes,” as Luke’s Gospel account puts it.—Luke 21:11.
No scientist, even if he was equipped with the finest of theories, tiltmeters and seismographs, would dream of predicting a sharp increase in highly destructive earthquakes 1,900 years in the future. How did Jesus do it? “I do not speak of my own originality,” said Jesus, “but the Father who remains in union with me is doing his works.” (John 14:10) Jesus’ predictions were not the result of any training in geology but were inspired by his heavenly Father, Jehovah God. Unlike scientists’ guesses, God’s predictions about the future prove true every time!
[Box on page 15]
If you live in an area of earthquake risk, remember—
Before an earthquake
● Check your home for earthquake hazards. Bolt down water heaters, place heavy objects on the floor or lower shelves. Brace or anchor shelves and top-heavy objects.
● Hold family earthquake drills. Teach members of the family how to turn off electricity, gas and water.
● Be sure you have a good fire extinguisher and first-aid kit.
● Keep a transistor radio on hand with fresh batteries.
During an earthquake
● Concentrate on staying calm. Remember, it will last only a minute or so.
● Turn off stoves and heaters.
● Stand in an open doorway or get under a table or desk.
● Stay away from windows, mirrors and chimneys. Do not run outdoors where you can be hit by falling roof tiles, building facades, etc.
● If outdoors, stay away from narrow streets, walls, power poles, etc. Try to get to an open area.
● Avoid elevators.
After an earthquake
● Check for injuries and fires. Get fires out fast.
● Check for gas leaks or electrical damage. Turn off gas or electricity if necessary.
● Get information from the radio. Do not use the telephone unless a real emergency requires it.
● Do not go sight-seeing.
● Be prepared for aftershocks.