The modified mercalli scale of earthquake intensity and. Modified mercalli intensities for nine earthquakes in. Mercalli scale smithsonian science for the classroom. Mmi value description of shaking severity summary damage description used on 1995 maps full description i. 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 modified mercalli intensity scale is a tool that anyone can use to report the effects of an earthquake in their immediate location. The three most important intensity scales in current use are the european macroseismic scale. Science briefs about new earthquake research written for nonscientists. Helps students understnad difference between magnitude and intensity.
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. 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. The preliminary relationship be tween the mmi and pga is reported to be a function of log. Modified mercalli earthquake scale the intensity of an earthquake is listed along with effects on the modified mercalli scale in this printable guide. The modified mercalli intensity mmi scale depicts shaking severity. Scientists record responses from many people who experience the. 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. Pdf the modified mercalli intensity scale revisions arising from. Rather, they classify earthquakes by the effects they have and the destruction they cause. Magnitude is related to the amount of seismic energy released at the hypocenter of the earthquake. If this table is garbled, try the plain text version. The modified mercalli intensity scale is commonly used in the united states by seismologists. The groundmotion parameters investigated were peak ground acceleration pga, velocity, displacement. 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.
The severity of an earthquake can be expressed in terms of both intensity and magnitude. Distribute h1 modified mercalli scale and display the scale on the projector. It is based on the amplitude of the earthquake waves. Modified mercalli intensity scale for additional information on statistics on percentage of uninhabitable residential units by construction type and mmi level, click here. The strength of an earthquake is usually measured on one of two scales, the modified mercalli scale and the richter scale. 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. Richter and presented in his landmark 1935 paper, where he called it the magnitude scale. Eiby seismological observatory, geophysics division, department of scientific and industrial research, wellington rueited for pllblicatioll 9 aligllj. Display the modified mercalli scale on the overhead projector. The modified mercalli intensity scale mm or mmi, descended from giuseppe mercallis.
Many portions of this brochure have been adapted from the 2008 south carolina earthquake guide originally developed by the. It was developed in 1931 by the american seismologists harry wood and frank neumann. Empirical relationships between modified mercalli intensity and. 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. Because of various shortcomings of the m l scale most. The modified mercalli scale of earthquake intensity and its use in. Ems98, the modified mercalli scale mm or mmi and the jma. Modified mercalli scale intensity effects pgagals i not felt. Modified mercalli intensity scale wikimili, the free. The zones indicate where there is a probability of 20 percent that.
When there is little damage, the scale describes how. Fun and educational resources including science fair ideas and earthquake science you can understand. Revisions in this version of the scale are shown in italics. Modified mercalli scale how is modified mercalli scale. An earthquake causes many different intensities of shaking in the area of the epicenter where it occurs. Explain that today, we will learn one method called the mercalli scale used to measure earthquakes. Pdf relationship between modified mercalli intensity and.
The mercalli intensity scale or more precisely the modified mercalli intensity scale is a scale to measure the intensity of earthquakes. 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. This was later revised and renamed the local magnitude scale, denoted as ml or m l. Pdf recent studies of the effects and modified mercalli mm intensities of new zealand earthquakes have established criteria that will. Review the roman numerals and read their descriptions. Pdf the modified mercalli intensity scale revisions. Unlike with the richter scale, the mercalli scale does not take into account energy of an earthquake directly. Modified mercalli intensity scale earthquake damage. Print out one copy of the kwat television script and cut them into cards. 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. Marginal and longperiod effects of large earthquakes. The modified mercalli intensity scale is a semiquantitative linear scale developed in 1931 by the american seismologists harry wood and frank neumann. It measures the shaking you feel during an earthquake.
Make transparencies of the modified mercalli scale and the wattsville map key to place. Modifiedmercalliintensityscale earthquakedamagereporting byjohnjacobschmidt,amrron intheimmediateaftermathofanearthquake,searchandrecoveryeffortswill. Using the modified mercalli scale to locate an epicenter earthquakes are classified using different scales. Earthquakes, now scanned and available online for example, u.
Richter 1956 gave a rewritten version of the mm scale which is referred to mm scale 1956 version. Modified mercalli intensity scale of 1931 the formation of. Wood and neumann gave a new version of the mcs scale, which came in use in usa as modified mercalli mm scale. Intensity scales, like the modified mercalli scale and the rossiforel scale, measure the amount of shaking at a particular location.
Relationship between modified mercalli intensity and peak. 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. 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 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. Usgs resources and links to outside educational resources. Using the modified mercalli scale to locate an epicenter. Modified mercalli intensity scale what is our evidence that we live on a changing earth.
Wood, harry o neumann, frank 1931, modified mercalli intensity scale of 1931 pdf, bulletin of the seismological society of america, 21 4. New zealand scientists have modified it further to suit new zealand conditions. Mercalli intensity scale simple english wikipedia, the. The formation of a satisfactory earthquake intensity scale. So the intensity of an earthquake will vary depending on where you are. Be sure you have an application to open this file type before downloading. The richter scale is a measure of the energy released during the earthquake. The modified mercalli scale is a measure of the amount of damage done by the earthquake. Modified mercalli scale uwi seismic research centre. This scale is composed of 12 increasing levels of intensity, designated by roman numerals, ranging from imperceptible shaking to. Handout primarily discussing the modified mercalli scale.
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