CNN: Three dozen earthquakes over the past week in central Arkansas shook shelves, rattled nerves and prompted speculation about their cause.
"Are they being being triggered or are they natural? That's something we don't know," Arkansas Geological Survey scientist Scott Ausbrook said Sunday.
The chances of so many temblors in the region in such a short time are "Powerball kind of odds," Ausbrook said. "What was unusual was to have four different areas in the state to be active in the same week."...