The modified mercalli intensity mmi scale depicts shaking severity. Richter 1956 gave a rewritten version of the mm scale which is referred to mm scale 1956 version. Mercalli scale smithsonian science for the classroom. It measures the effects of an earthquake at a given location, distinguished from the earthquakes inherent force or strength as measured by seismic magnitude scales such as the. In new zealand, where earthquakes occur from near the surface right down to a depth of over 600 km, the modified mercalli intensity scale is a better indicator of an earthquakes effects on people and their environment. Review the roman numerals and read their descriptions.
The strength of an earthquake is usually measured on one of two scales, the modified mercalli scale and the richter scale. Make transparencies of the modified mercalli scale and the wattsville map key to place. If this table is garbled, try the plain text version. Scientists record responses from many people who experience the. Be sure you have an application to open this file type before downloading. An earthquake causes many different intensities of shaking in the area of the epicenter where it occurs. Modified mercalli intensity scale of 1931 the formation of. Modified mercalli scale how is modified mercalli scale. Wood and neumann gave a new version of the mcs scale, which came in use in usa as modified mercalli mm scale. Many portions of this brochure have been adapted from the 2008 south carolina earthquake guide originally developed by the.
Modified mercalli intensity scale wikimili, the free. Relationship between modified mercalli intensity and peak. Unlike with the richter scale, the mercalli scale does not take into account energy of an earthquake directly. The modified mercalli intensity scale is a tool that anyone can use to report the effects of an earthquake in their immediate location.
The modified mercalli intensity value assigned to a specific site after an earthquake has a more meaningful measure of severity to the nonscientist than the. The mercalli intensity scale or more precisely the modified mercalli intensity scale is a scale to measure the intensity of earthquakes. It is based on the amplitude of the earthquake waves. Earthquakes, now scanned and available online for example, u.
Helps students understnad difference between magnitude and intensity. The modified mercalli intensity scale is commonly used in the united states by seismologists. Empirical relationships between modified mercalli intensity and. Pdf recent studies of the effects and modified mercalli mm intensities of new zealand earthquakes have established criteria that will. The modified mercalli intensity value assigned to a specific site after an earthquake has a more meaningful measure of severity to the nonscientist than the magnitude because intensity refers to the effects actually experienced at that place. The modified mercalli intensity scale mm or mmi, descended from giuseppe mercallis mercalli intensity scale of 1902, is a seismic intensity scale used for measuring the intensity of shaking produced by an earthquake. It measures the shaking you feel during an earthquake. Modified mercalli intensity scale for additional information on statistics on percentage of uninhabitable residential units by construction type and mmi level, click here. Ems98, the modified mercalli scale mm or mmi and the jma. The severity of an earthquake can be expressed in terms of both intensity and magnitude. Fun and educational resources including science fair ideas and earthquake science you can understand. Modified mercalli intensity scale earthquake damage. The intensity of the earthquakes is valued according to the richter scale charles francis richter 2641900 3091985 or the modified mercalli scale giuseppe mercalli 2151850 1931914.
Rather, they classify earthquakes by the effects they have and the destruction they cause. Wood, harry o neumann, frank 1931, modified mercalli intensity scale of 1931 pdf, bulletin of the seismological society of america, 21 4. The preliminary relationship be tween the mmi and pga is reported to be a function of log. The modified mercalli scale of earthquake intensity and its use in. Using the modified mercalli scale to locate an epicenter. Modified mercalli scale uwi seismic research centre. Modified mercalli earthquake scale the intensity of an earthquake is listed along with effects on the modified mercalli scale in this printable guide. Mmi value description of shaking severity summary damage description used on 1995 maps full description i. The three most important intensity scales in current use are the european macroseismic scale. New zealand scientists have modified it further to suit new zealand conditions. Modified mercalli scale intensity effects pgagals i not felt. The zones indicate where there is a probability of 20 percent that. Magnitude is related to the amount of seismic energy released at the hypocenter of the earthquake. The modified mercalli intensity scale mm or mmi, descended from giuseppe mercallis.
Display the modified mercalli scale on the overhead projector. This scale is composed of 12 increasing levels of intensity, designated by roman numerals, ranging from imperceptible shaking to. Revisions in this version of the scale are shown in italics. Explain that today, we will learn one method called the mercalli scale used to measure earthquakes. Handout primarily discussing the modified mercalli scale. Usgs resources and links to outside educational resources. Even if conventional communications, commercial radio and television, and internet are disrupted, the reports sent in by radio operators can provide great insight as to the size and scope of the incident. The mercalli scale is a rather arbitrary set of definitions based upon what people in the area feel, and their observations of damage to buildings around them. The modified mercalli intensity scale mm or mmi, descended from giuseppe mercalli s mercalli intensity scale of 1902, is a seismic intensity scale used for measuring the intensity of shaking produced by an earthquake. The modified mercalli scale is a measure of the amount of damage done by the earthquake. Eiby seismological observatory, geophysics division, department of scientific and industrial research, wellington rueited for pllblicatioll 9 aligllj. The modified mercalli scale of earthquake intensity and. Distribute h1 modified mercalli scale and display the scale on the projector.
Because of various shortcomings of the m l scale most. The modified mercalli intensity scale is a semiquantitative linear scale developed in 1931 by the american seismologists harry wood and frank neumann. Pdf relationship between modified mercalli intensity and. Intensity scales, like the modified mercalli scale and the rossiforel scale, measure the amount of shaking at a particular location. Modified mercalli intensity scale mmi abag resilience. So the intensity of an earthquake will vary depending on where you are. Modifiedmercalliintensityscale earthquakedamagereporting byjohnjacobschmidt,amrron intheimmediateaftermathofanearthquake,searchandrecoveryeffortswill. The groundmotion parameters investigated were peak ground acceleration pga, velocity, displacement. The first scale furnishes an evaluation magnitude of the quantity of freed energy, while the seconds scale assigns a degree to the effects on the.
The richter scale is a measure of the energy released during the earthquake. As you can see here, as the numbers get higher, the more you feel the shaking. This was later revised and renamed the local magnitude scale, denoted as ml or m l. Pdf the modified mercalli intensity scale revisions. What is the difference between magnitude and intensity. Print out one copy of the kwat television script and cut them into cards. Modified mercalli intensities for nine earthquakes in. Pdf the modified mercalli intensity scale revisions arising from. Richter and presented in his landmark 1935 paper, where he called it the magnitude scale. When there is little damage, the scale describes how. Modified mercalli intensity mmi scale, based on the engineering groundmotion parameter, as the peak ground acceleration pga, inferred from the groundmotion attenuation characteristic of myanmar. Modified mercalli intensity scale mmi the modified mercalli intensity mmi estimates the intensity of shaking from an earthquake at a specific location or over a specific area by considering its effects on people, objects, and buildings. The richter scale also called the richter magnitude scale or richters magnitude scale is a measure of the strength of earthquakes, developed by charles f. It was developed in 1931 by the american seismologists harry wood and frank neumann.
This is apparent from the table of correlations established by gorshkov and shenkareva 1958. However, the two terms are quite different, and they are often confused. Using the modified mercalli scale to locate an epicenter earthquakes are classified using different scales. Mercalli intensity scale simple english wikipedia, the. The formation of a satisfactory earthquake intensity scale. Modified mercalli intensity scale what is our evidence that we live on a changing earth. Science briefs about new earthquake research written for nonscientists. It measures the effects of an earthquake at a given location, distinguished from the earthquakes inherent force or strength as measured by seismic magnitude scales such as.
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