Can someone translate this:
JordanJ[1991]Jdeveloped a formalism for detecting slow precursors to earthquakes based on observations of the Earth's free oscillations. He derived an inequality that states that an earthquake must be precursive (non-zero moment release before the high-frequency origin time) if the characteristic duration of the moment-rate function is greater than a simple expression involving the skewness of the moment-rate function and the centroid time shift.

I can't be the only one reading here not able to understand this - specifically what is:
1 - non-zero moment release before the high-frequency origin time - does this mean that some energy is being released prior to the detected earthquake?
2 - characteristic duration of the moment-rate function
3 - simple expression involving the skewness of the moment-rate function
4 - centroid time shift

I haven't quite gotten to any geophysics courses. Unfortunately I didn't read past that point.

Canie
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