Reader inquiry: "I thought Thailand never had any earth quakes"

I recommend a  Bangkok Post article published May 6, 2014, with a graphic map of

• "Fault Lines under Observation"

Sakon Nakhon Province seems to be split according to a  Chulalongkorn University map

North: moderate (4 Mercalli-intensity)
South: Slight  (3 Mercalli intensity)

Thailand's most dangerous fault lines are in the north and west, mostly along the Myanmar and Laos  borders.
Prior to this months earthquake there have been frequent minor tremors. 

A earthquake of greater intensity than this month was in 2011 

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