Earthquakes

Since the beginning of 2009, Central Oklahoma has experienced a substantial increase in seismic activity, too much to be random, researchers think. Drilling wastewater disposal in injection wells is a likely contributing factor, they said.

Nearly 100 small earthquakes that hit northeast Ohio throughout 2011 and into early 2012 were triggered by a now-shuttered wastewater disposal well in Youngstown, according to a Columbia University researcher.

While earlier research in Texas’ Barnett Shale linked drilling waste injection into underground storage wells with increased seismic activity, new work in the Eagle Ford by the same geologist suggests that drawing liquids out of the ground can induce earthquakes there.

Two earthquakes that recently shook the area around the East Texas town of Timpson were unlikely to have been caused by natural gas drilling or drilling waste disposal activities, according to the Railroad Commission of Texas (RRC).

Two small earthquakes in northwest England that occurred earlier this year at some natural gas drilling sites likely were caused by hydraulic fracturing (fracking), according to a report issued on Wednesday by UK-based Cuadrilla Resources Ltd.

A series of earthquakes along the central Gulf of California coast of Baja California Monday through Wednesday were felt widely in Mexico and the western United States, but San Diego-based Sempra Energy reported that the quakes had no impact on its Costa Azul liquefied natural gas (LNG) receiving terminal or connecting transmission pipelines, which cut across the northern-most stretch of North Baja.