To me the building with people inside of it represents a social structure. This could be your circle of friends, your place in your community or church, possibly even your family - but this is least likely because you didn't mention any of them in the building. The earthquake represents breaking this structure down in a big way. The magnitude of earthquakes suggests recent discontent in your life like some unpleasant change. Perhaps the loss of a friend(s) or change in your own social status is what this dream might be pointing to. Earthquakes coincidentally coinside to the element of earth - gee go figure. Your astrological sign may indicate which element dominates within you the most. If your element is not Earth then the Earthquake represents an unwanted change that was imposed on you by no fault of your own. If your main element is earth then the change may still have been unwanted, but was necessary and for your own good.
The police man represents your own inner authority and peace keeper. By saving you from the rubble your inner authority is telling you that regardless of whatever changes you endured, you're ok and your life will go on.
Also keep in mind the foresight of one's own mind is actually incredibly fasinating. If no major changes have occured in your social life - friends, co-workers, those who you hang out with or community groups etc - then this dream may actually be a warning that such changes are comming. For example I used to dream of Earthquakes wrecking my school before I graduated and indeed after I graduated I only kept in touch with a handfull of people from my class.
Thats just my interpretation (they tend to be way right or totally out in left field (IMG:
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