A M6.7 Chile aftershock that must have made the table dance in the apartment where HD stayed for her semester abroad. 3 1/2 hours later a M6.8 in Papua.
M6+ quakes occur once about every 2 days, but M6.5+ quakes would be less common.

Roger has tested whether M6+ quakes at distance cluster in time, and the answer was "no", but it still seems to me that the answer whoule be "maybe"

Chris