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Different shape intensity from magnitude of an earthquake movements?
Wiki User
∙ 12y ago
There are two ways of describing an earthquake;by intensity and by magnitude.
When we talk of intensity, we are referring to the effects and damage produced by the earthquake. It is determined by going to all the areas affected by the earthquake and observing the damage, as well as recording the experiences of the people there. The first intensity scale was developed by Giuseppe Mercalli in 1902.
This has since been improved by the use of strong motion seismometers which are able to measure ground accelerations and so produce a less subjective assessment of intensity. The value of intensity can vary from place to place. In the US the intensity of an earthquake is measured using the Modified Mercalli scale and in Europe the Macroseismic scale is used (which appears to be an updated version of the original Mercalli intensity scale).
Earthquake magnitude on the other hand is a single value (it should be the same no matter where it is measured) and is based on the amount of seismic energy produced by an earthquake. It can be estimated from the amplitude of seismic waves recorded by a seismometer (and requires scaling to account for the distance of the recording station from the earthquakes epicentre) or directly based on the cross sectional area of the fault which moved, the average displacement and the shear modulus of the rockmass. In the past the Richter magnitude scale was commonly used however seismologists now use the Moment magnitude scale.
I hope it would help you :)
Wiki User
∙ 12y ago
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How is the intensity and magnitude of an earthquake measured?
Earthquakes are measure with a seismograph which indicates the intensity of earth crust´s movements this measurement is call Richter 1 being less intensity and 10 being major intensity.
How is tidal energy made?
it is caused by the shocks of an earthquake and the earthquake is caused by the movements of the plates at the bottom of the earth
What plate movements happened during Kobe's earthquake?
Eurasian and Pacific
What is an earthquake and situations that earthquakes occur?
An earthquake is a sudden and violent shaking of the ground, it is caused by movements within the earth's crust or volcanic action.
What is the popular term for smaller movements of the earth's crust that follow an earthquake?
Aftershock........... I think >:D
How is the intensity and magnitude of an earthquake measured?
Earthquakes are measure with a seismograph which indicates the intensity of earth crust´s movements this measurement is call Richter 1 being less intensity and 10 being major intensity.
What is the measurement of an earthquake's strength based on seismic waves and movements along faults?
An earthquake's magnitude is a measure of its strength.
What is sesmometer?
a measuring instrument for detecting and measuring the intensity and direction and duration of movements of the ground (as an earthquake)
What is the surface movement magnitude and intensity at Yellowstone national park?
The normal surface movement, magnitude, and intensity at Yellowstone National Park varies from about 1.5 to 3.0. These would be barely noticeable by the average person. But the forest rangers and geologists would notice and be aware of any larger movements.
What are there movements of an earthquake?
it shakes all aroud
How do scientists study earthquakes?
With a really big ruler! No, not quite. There are two ways in which scientists quantify the size of earthquakes: magnitude and intensity. Magnitude is a measure of the amount of energy released during an earthquake, and you've probably heard news reports about earthquake magnitudes measured using the Richter scale. Something like, "A magnitude 7.3 earthquake struck Japan today. Details at ten." Did you ever wonder why, if it's that important, they just don't tell you right away? The Richter scale was invented, logically enough, in the 1930s by Dr. Charles Richter, a seismologist at the California Institute of Technology. It is a measure of the largest seismic wave recorded on a particular kind of seismograph located 100 kilometers (about 62 miles) from the epicenter of the earthquake. Think of a seismograph as a kind of sensitive pendulum that records the shaking of the Earth. The output of a seismograph is known as a seismogram. In the early days, seismograms were produced using ink pens on paper or beams of light on photographic paper, but now it's most often done digitally using computers. The seismograph that Dr. Richter used amplified movements by a factor of 3000, so the waves on the seismograms were much bigger than those that actually occurred in the Earth. The epicenter of an earthquake is the point on the Earth's surface directly above the source, or focus, of the movement that causes the quake. Dr. Richter studied records from many earthquakes in southern California, and realized that some earthquakes made very small waves whereas others produced large waves. So, to make it easier to compare the sizes of the waves he recorded, Richter used the logarithms of the wave heights on seismograms measured in microns (1/1,000,000th of a meter, or 1/1000th of a millimeter). Remember, you have to be using a particular kind of seismograph located 100 km from the epicenter when you make the measurement; otherwise, all sorts of complicated calculations have to be made. That's why seismologists spend so many years in college! A wave one millimeter (1000 microns) high on a seismogram would have a magnitude of 3 because 1000 is ten raised to the third power. In contrast, a wave ten millimeters high would have a magnitude of 4. For reasons that we won't go into, a factor of 10 change in the wave height corresponds to a factor of 32 change in the amount of energy released during the earthquake. In other words, a magnitude 7 earthquake would produce seismogram waves 10 x 10 = 100 times as high and release energy 32 x 32 = 1024 times as great as a magnitude 5 earthquake. The Richter scale is open-ended, meaning there is no limit to how small or large an earthquake might be. Due to the nature of logarithms, it is even possible to have earthquakes with negative magnitudes, although they are so small that humans would never feel them. At the other end of the spectrum, there should never be an earthquake much above magnitude 9 on the Earth simply because it would require a fault larger than any on the planet. The largest earthquake ever recorded on Earth was a magnitude 9.5 that occurred in Chile in 1960, followed in size by the 1964 Good Friday earthquake in Alaska (magnitude 9.2), a magnitude 9.1 earthquake in Alaska during 1957, and a magnitude 9.0 earthquake in Russia during 1952. Two large earthquakes, one a magnitude 9.0 and one a magnitude 8.2, occurred on Dec. 26, 2004 and March 28, 2005, respectively, along the same fault zone off the coast of Sumatra, Indonesia. The list of really large earthquakes in the previous paragraph brings up another interesting point. Five earthquakes of magnitude 9 or above have been recorded during the past 45 years, which averages out to one every decade. It turns out that earthquake occurrences seem to follow what is called a power-law distribution, meaning that if there is on average on magnitude 9 earthquake every ten years somewhere in the world, then on average there should be one magnitude 8 earthquake every year, 10 magnitude 7 earthquakes every year, and 100 magnitude 6 earthquakes every year. So, if someone "predicts" that a magnitude 6 earthquake will occur somewhere in the world during the next week, don't be too impressed if it happens because random probability tells us that there should be a magnitude 6 earthquake somewhere in the world every 365/100 = 3.65 days! In reality, things are a little more complicated. But, you get the picture. What did people do before the Richter scale was invented? To some degree, one of the same things that we do today. They observed the intensity or effects of an earthquake at different locations. Whereas the magnitude of an earthquake is a single number regardless of where it's felt, intensity will vary from place to place. In general, the intensity will be much greater near the epicenter than at large distances from the epicenter. This decrease in intensity with distance is known as attenuation. Imagine it this way: If I drop a rock into a pool of water, the difference between magnitude and intensity is similar to the difference between the height of the splash exactly where I drop the rock and the height of the waves all over the pool. Earthquake intensity is most often measured using the modified Mercalli scale, which was invented by the Italian geologist Giuseppi Mercalli in 1902 and uses Roman numerals from I to XII. In the United States, we use the modified Mercalli scale, which was adjusted to account for differences in buildings between Italy and southern California. An earthquake intensity of I is generally not felt, and an intensity of XII represents total destruction of buildings. Some kinds of geologic deposits, most notably water saturated muds, amplify seismic waves and may produce intensities much greater than those for nearby areas underlain by bedrock. Thus, after an earthquake seismologists can interview people and make maps showing the intensity of an earthquake in different areas to better understand the influence of rock or soil type on seismic waves.
What are the two ways to measure an earthquake?
There are two main ways to measure earthquakes. One is the richter scale, which directly measures the energy released by the earthquakes. It's logarithmic, with each increasing order of magnitude being several times larger than the previous one. Seismographs are used for these measurements. Another way of measuring the physical impact of an Earthquake is the Mercalli scale, which is based on damage and other changes to the surrounding environment. They both have their uses and are very effective.
Explain the main cause of earthquakes and their effects?
The primary cause of an earthquake is faults on the crust of the earth. The cracks or sudden slips of the land are known as faults or fault planes. The point of origin of the earthquake is inside the earth and is known as the hypocenter. Maximum destruction is caused at the epicenter, the surface above the hypocenter. When there are sudden movements in the various layers of the earth, crust or mantle, concentric waves are produced. These waves are known as seismic waves and are of three types; Primary Waves (P-Waves), Secondary Waves (S-Waves) and Surface Waves (L-Waves). These waves have different patterns of movement. Earthquakes usually have foreshocks and aftershocks. The main earthquake or the one with the maximum magnitude is known as the main shock. Its intensity is calculated by the magnitude of seismic waves, measured with the help of a seismograph. The measurement is taken on the Richter scale.
How is tidal energy made?
it is caused by the shocks of an earthquake and the earthquake is caused by the movements of the plates at the bottom of the earth
What is something produced by movements of faults around the lithosphere?
Earthquake
Is an Earthquake geological?
Yes, because they are created by plate movements.
What is pressure caused by large movements in earth called?
earthquake
