Use this geological calculation for a transparent first-pass interpretation of measured rock, soil, fluid, well, stratigraphic, isotopic, geophysical, or seismic data under an explicitly selected model.

MMI level

Modified Mercalli intensity level as an integer from 1 (I) to 12 (XII).

Look up the Modified Mercalli intensity (I-XII) shaking name and typical effects for a given integer intensity level. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Shaking

Standard shaking-strength name for the level.

Roman numeral

Roman numeral of the intensity level.

Effects

Typical observed effects at this intensity.

• Seismic magnitudes, moments, travel times, velocities, resolution, and energy depend on instrument correction, Earth model, phase picking, geometry, attenuation, radiation pattern, bandwidth, and calibration range. Magnitude scales are not universally interchangeable.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Compare independent measurements and models, retain units and analytical metadata, propagate uncertainty, and validate interpretations against logs, cores, maps, laboratory data, or field observations.

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• Rock Density Lookup

  Look up the typical dry bulk density range in g/cm3 for a common rock type.