Gutenberg–Richter law


Gutenberg–Richter law

In seismology, the Gutenberg–Richter law [ B. Gutenberg and C.F. Richter, "Seismicity of the Earth and Associated Phenomena", 2nd ed. (Princeton, N.J.: Princeton University Press, 1954), pages 17-19 ("Frequency and energy of earthquakes").] expresses the relationship between the magnitude and total number of earthquakes in any given region and time period. : !,{log N} = A - b M or: !,N = 10^{A - b M}

Where:
* !, N is the number of events in a given magnitude range
* !, M is a magnitude range
* !, A and !, b are constants

The relationship was first proposed by Charles Francis Richter and Beno Gutenberg. The relationship is surprisingly robust and does not vary significantly from region to region or over time.

The constant "b" is typically equal to 1.0. This means that for every magnitude 4.0 event there will be 10 magnitude 3.0 quakes and 100 magnitude 2.0 quakes. A notable exception is during earthquake swarms when the b-value can become as high as 2.5 indicating an even larger proportion of small quakes to large ones. A b-value significantly different from 1.0 may suggest a problem with the data set; e.g. it is incomplete or contains errors in calculating magnitude. The "roll off" of the b-value is an indicator of the completeness of the data set at the low magnitude end.

The "a-value" is of less scientific interest and simply indicates the total seismicity rate of the region.

Modern attempts to understand the law involve theories of self-organized criticality or self similarity.


Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Power law — A power law is any polynomial relationship that exhibits the property of scale invariance. The most common power laws relate two variables and have the form:f(x) = ax^k! +o(x^k),where a and k are constants, and o(x^k) is of x. Here, k is… …   Wikipedia

  • Beno Gutenberg — Infobox Scientist name = Beno Gutenberg box width = image width =150px caption = Beno Gutenberg birth date = June 4, 1889 birth place = Darmstadt death date = January 25, 1960 death place = residence = citizenship = nationality = Germany… …   Wikipedia

  • Aftershock — Part of a series on earthquakes Types Foreshock • Aftershock • Blind thrust Doublet • Interplate …   Wikipedia

  • Scientific phenomena named after people — This is a list of scientific phenomena and concepts named after people (eponymous phenomena). For other lists of eponyms, see eponym. NOTOC A* Abderhalden ninhydrin reaction Emil Abderhalden * Abney effect, Abney s law of additivity William de… …   Wikipedia

  • Earthquake — For other uses, see Earthquake (disambiguation). Global earthquake epicenters, 1963–1998 …   Wikipedia

  • Olami–Feder–Christensen model — In physics, in the area of dynamical systems, the Olami–Feder–Christensen model is an earthquake model conjectured to be an example of self organized criticality where local exchange dynamics are not conservative. Despite the original claims of… …   Wikipedia

  • Chaos theory — This article is about chaos theory in Mathematics. For other uses of Chaos theory, see Chaos Theory (disambiguation). For other uses of Chaos, see Chaos (disambiguation). A plot of the Lorenz attractor for values r = 28, σ = 10, b = 8/3 …   Wikipedia

  • The Long Tail — The phrase The Long Tail (as a proper noun with capitalized letters) was first coined by Chris Anderson in an October 2004 Wired magazine article [ [http://www.wired.com/wired/archive/12.10/tail.html The Long Tail ] by Chris Anderson, Wired , Oct …   Wikipedia

  • Self-organized criticality — In physics, self organized criticality (SOC) is a property of (classes of) dynamical systems which have a critical point as an attractor. Their macroscopic behaviour thus displays the spatial and/or temporal scale invariance characteristic of the …   Wikipedia

  • Réplica (sismología) — Saltar a navegación, búsqueda Una réplica es un movimiento sísmico que ocurre en la misma región en donde hubo un temblor o terremoto central (generalmente dentro de una longitud cercana de ruptura). Estos temblores son una consecuencia de… …   Wikipedia Español


Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.