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Moonquakes: mechanisms and relation to tidal stresses
Science (New York, N.Y.)
|May 27, 1977
Summary
Tidal stresses and ambient tectonic stress explain moonquake mechanisms, including depth, periodicity, and polarity reversals. These small stresses align with the low magnitudes observed in moonquakes.
Area of Science:
- Geophysics
- Planetary Science
- Seismology
Background:
- Moonquakes are seismic events originating on the Moon.
- Understanding moonquake mechanisms is crucial for lunar geology and exploration.
- Previous studies have observed moonquake features but lacked a comprehensive mechanistic explanation.
Purpose of the Study:
- To interpret the mechanisms driving moonquakes.
- To correlate observed moonquake features with theoretical stress models.
- To provide a unified explanation for moonquake depth, periodicity, and polarity reversal.
Main Methods:
- Combining observational data of moonquake features.
- Performing theoretical calculations of tidal stresses on the Moon.
- Integrating tidal stresses with a postulated ambient tectonic stress model.
Main Results:
- Tidal stresses and ambient tectonic stress adequately explain moonquake depth and periodicity.
- The proposed stress model accounts for observed polarity reversals in moonquakes.
- Calculated stresses are small (approximately 1 bar), consistent with low moonquake magnitudes.
Conclusions:
- Tidal and tectonic stresses are the primary drivers of moonquake activity.
- The proposed model offers a robust explanation for diverse moonquake characteristics.
- This research enhances our understanding of the Moon's internal dynamics and seismic behavior.
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