A successful prediction vs. a successful track record.

The interesting case history of the Jupiter effect, Iben Browning and the 1990 prediction.

Components/types of predictions:

• as to future location of earthquakes.
• maximum magnitude earthquake for an area.
• recurrence interval for a given size EQ for an area.
• prediction of location, size, and time frame of earthquake.

Future location and size of earthquakes (neglecting time component):

• plate setting, historical record, microseismicity.
• Meers fault in Oklahoma.
• identification of active faults by geomorphic signature and trenching (e.g. Kerry Sieh, Pallett Creek and the San Andreas).
• paleoseismic indicators (liquefaction features and tsunami deposits, e.g. W Washington).
• seismic gaps and locking geometries.

Estimation of recurrence interval:

• Gutenburg-Richter log-log frequency-size relationship.
• fractals and fracturing.
• 40% chance of great EQ in southern CA in next 30 years.
• extending the record with trenching.
• for intraplate EQs.
• use of these estimates for building codes.

Prediction based on dilatancy hardening theory and the use of precursors.

• dilatancy in the laboratory.
• expression as precursors in the field: foreshocks, surface bulges, changes in water level, changes in seismic velocity, changes in radon content of water, localized changes in earths magnetic field.
• Haicheng, NE China prediction in 1976 of 7.3 RM EQ, 10% success rate claimed in China.
• overall success questionable?

Cost of a precursor monitoring program?

H.D. Maher Jr., 3/2/98

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