Texas oil and gas industry 'almost certainly' caused 59% of earthquakes since 1975, says study

Nearly two-thirds of Texas earthquakes over the past 40 years can be linked to the oil and gas industry, says a study by the University of Texas and Southern Methodist University, published today in the journal Seismological Research Letters. The study "concludes that activities associated with petroleum production 'almost certainly' or 'probably' set off 59 percent of earthquakes across the state between 1975 and 2015," Anna Kuchment reports for The Dallas Morning News. "Another 28 percent were 'possibly' triggered by oil and gas activities. Scientists deemed only 13 percent of the quakes to be natural." (Morning News graphic)

The Texas Railroad Commission, which regulates the state's oil and gas industry, was quick to dismiss the study as arbitrary, Kuchment writes. "In November 2014 the commission tightened its rules for disposal wells. Since then, it has received 51 disposal-well applications. Of these, 22 permits were issued with special conditions, such as requirements to reduce daily maximum injection volumes and pressure and to record volumes and pressures daily as opposed to monthly. Nine permits were issued without special conditions. The rest were either withdrawn, returned to the applicant for more information, protested and sent to a hearing, or are still pending."

The study links man-made earthquakes back to the early days of the oil and gas industry, Kuchment writes. "The first man-made quake struck in 1925 in the Goose Creek oil field along the Gulf Coast east of Houston. Humble Oil, a precursor of Exxon, had extracted so much oil that the ground sank and caused houses to shake and dishes to crash to the floor. Over the years, different petroleum production methods have triggered quakes, including oil and gas extraction and enhanced recovery, in which operators pump water or carbon dioxide into reservoirs to boost the flow of oil. Each method can, in rare cases, raise or lower pressure on faults and cause them to rupture."