An earthquake occurred in the early hours of Dec. 9 in Mineral Wells, the same general North Texas area where news reports say more than a dozen other minor earthquakes have been recorded in the past six weeks. As a result, C. Christopher Cowan’s phone started ringing more persistently.

Who was calling the partner in The Cowan Law Firm in Dallas? Area property owners, asking about the progress of a pending lawsuit filed in Johnson County, about an hour away from Mineral Wells. The lawsuit alleges that oil and gas companies that engaged in hydraulic fracturing in that region are responsible for the increased risk of quakes.