Reply to “Comment on ‘A Historical Review of Induced Earthquakes in Texas’ by Cliff Frohlich, Heather DeShon, Brian Stump, Chris Hayward, Matt Hornbach, and Jacob I. Walter” by Steve Everley

Abstract

Our paper (Frohlich et al. , 2016) reviewed the literature concerning Texas earthquakes to reach four conclusions: (1) induced earthquakes have occurred in several geographic locations, including the east, northeast, west, and Gulf Coast of Texas; (2) induced earthquakes are not exclusively a recent phenomenon—there exist plausible, documented examples as early as 1925; (3) several different industry practices have caused induced earthquakes: these include not only injection disposal of fluid wastes but also production from shallow reservoirs and secondary recovery activities such as waterflooding; and (4) beginning in 2008 rates of Texas earthquakes having magnitudes of 3 and greater increased from about 2 per year to 12 per year, and this increase is attributable to induced earthquakes. The week following the online publication of our review in SRL , Everley (2016b) published his critique of our five‐question test in Energy In Depth , a blogsite “launched by the Independent Petroleum Association of America in 2009 [as] a research, education and public outreach campaign focused on getting the facts out about the promise and potential of responsibly developing America’s onshore energy resource base” (Energy In Depth, 2016). It is productive to the assessment of these important issues that critics frame their critiques of the science in the peer‐reviewed literature. We thus applaud Everley’s decision to publish a Comment on our paper in SRL (Everley, 2016a), as it is a step in this direction. Everley’s comment does not challenge the conclusions of our paper directly; rather, he criticizes two features of the question‐based test we apply to individual earthquakes to assess evidence suggesting an induced cause. His first and principal objection is that, unlike a previous test (Davis and Frohlich, 1993), our test no longer includes questions about fluid pressures at the well bottom and their mechanical effects at …