6.6 på richter skalan
Richter scale
Measure of an earthquake's strength
This article is about the earthquake magnitude scale introduced bygd Charles Richter in For a review of earthquake magnitude scales, see seismic magnitude scales. For the musical scale used for tuning harmonicas, see Richter tuning. For the single by EPMD, see Richter Scale (song).
The Richter scale[1] (), also called the Richter magnitude scale, Richter's magnitude scale, and the Gutenberg–Richter scale,[2] is a measure of the strength of earthquakes, developed bygd Charles Richter in collaboration with Beno Gutenberg, and presented in Richter's landmark paper, where he called it the "magnitude scale".[3] This was later revised and renamed the local magnitude scale, denoted as ML or ML&#;.[4]
Because of various shortcomings of the original ML&#; scale, most seismological authorities now use other similar scales such as the moment magnitude scale (Mw&#;) to report earthquake magnitudes, but much of the news media still erroneously refers to these as "Richter" magnitudes. All magnitude scales retain the logarithmic character of the original and are scaled to have roughly co
Richterskalan
Richterskalan är en skala som tidigare användes för att ange styrkan hos jordbävningar, men som sedan början av talet ersatts med Momentmagnitudskalan, bland annat vid rapportering från den amerikanska myndigheten U.S. Geological Survey.[1] De två skalorna ger liknande värden för mindre jordbävningar, medan Richterskalan kan underskatta storleken hos verkligt stora jordbävningar. I nyhetsrapportering anges ofta storleken hos en jordbävning med "Richterskalan", trots att storleksbestämningen i själva verket skett med momentmagnitudskalan.
Skalan är en logaritmisk skala där varje steg (magnitud) motsvarar en ökning av amplituden på vågrörelsen (skakningen) med 10 gånger. Detta motsvarar ca 32 gånger mer energi. En jordbävning på 3–4 är knappt märkbar; en på 8 eller mer kan ödelägga städer om den inträffar i tättbebyggda områden. Jordbävningar på cirka 8,0 inträffar i genomsnitt en gång per år medan jordbävningar på mer än 9 inträffar mer sällan. Skalan kan även anta negativa värden, men så svaga jordbävningar är svåra att detektera.
Bakgrund
[redigera | redigera wikitext]Skalan togs fram år av Charles Richter i samarbete med Beno Gutenberg vid Cal
| Using the Richter Scale to Measure Earthquakes |
Each increase of one magnitude unit on the Richter scale represents a tenfold increase in the amplitude of the seismic waves, and a fold increase in the amount of energy released. For example, a magnitude earthquake is 10 times stronger than a magnitude earthquake, and 31 times stronger than a magnitude earthquake.
The Richter scale is a base logarithmic scale, which means that each order of magnitude is 10 times more intense than the last one. In other words, a two is 10 times more intense than a one and a three is times greater. In the case of the Richter scale, the increase is in wave amplitude.
The Richter scale runs from 1 - 10 (1 being the least in magnitude and 10 being the greatest), but it is logarithmic. This means that for each 1 point in increase on the scale we get 10 times more ground shaking. Let's look at an example. Say we have a magnitude 1 earthquake on the Richter scale, which is the lowest magnitude earthquake. Compare that with a magnitude 2 earthquake, which is only one step higher (remember, the scale runs from 1 - 10), and you now have 10 times more ground shaking than with the magnitude 1 qua