# Moment Magnitude Model

## Class Name

• RMomentMagnitudeModel

## Location in Objects Pane

• Models > Model > Hazard > Earthquake > Magnitude > Moment Magnitude

## Model Description

### Model Form

$$M = {\vartheta _1} \cdot {\log _{10}}(G \cdot A \cdot D \cdot {10^7}) - {\vartheta _2} + \varepsilon$$ where $${G}$$∙$${A}$$∙$${D}$$∙$${10^7}$$ = seismic moment

• Yes

## Properties

### Object Name

• Name of the object in Rt
• Allowable characters are upper-case and lower-case letters, numbers, and underscore (“_”).
• The name is unique and case-sensitive.

### Display Output

• Determines whether the model is allowed to print messages to the Output Pane.

### Shear Modulus

• $${G}$$ = Shear modulus which is typically set as 30.109 N/m2

### Rupture Area

• $${A}$$ = Rupture area in m2

### Rupture Displacement

• $${D}$$ = Rupture displacement in m

### Theta1

• $${\vartheta _ 1}$$ = Model parameter which is typically set as 2/3.

### Theta2

• $${\vartheta _ 2}$$ = Model parameter which is typically set as 10.7.

### Epsilon

• $${\varepsilon}$$ = Model error

## Output

• $${M}$$ = Magnitude
• The output is an automatically generated generic response object, which takes the object name of the model plus “Response”.