Professor M. Charles Gilbert presented several answers on the latest earthquake activity in Oklahoma while being a guest speaker at the Altus Rotary Club luncheon on Tuesday, Aug. 5, at Western Oklahoma State College. Several Rotarians were also recognized during the luncheon.
Professor Gilbert has a background specializing in geological and petrological studies and has taught at several universities for over 39 years until retiring from the University of Oklahoma in 2007.
After a brief introduction to the nature of earthquakes, Gilbert began to focus on the question, “Can humans make earthquakes?”
“Of course we can cause them. We do it all the time in the oil and gas industry,” Professor Gilbert said. “We do it by putting thumpers on the ground, or blowing up dynamite in the ground, to send out waves to study the upper few miles of the structure of the earths crust.” The purpose of doing so is to study those layers for oil reservoirs and to find out how to drill, however, those deliberate quakes are too small to be felt.
Looking specifically at Oklahoma, Gilbert offered three possible answers for the recent earthquakes. It could simply be a natural process of increased stress to the North American Plate causing the faults in Oklahoma to produce more rock slippage. Or maybe human history is so short that its impossible to analyze the “normal” frequency of earthquakes over a larger span of a few thousand years. And then finally, there are those who say that we are pumping more fluid waste into the ground.
Crediting Seismologist Katy Keranen, who studies Oklahoma earthquakes, Gilbert said that Enhanced Recovery Wells (EOR), which pump a large volume of salt water thousands of feet into the ground as being one of the major causes for increased activity. Scientists have argued that pumping waste disposal water into the ground near the Prague fault system in northeast Oklahoma causes extra vibrations.
Gilbert explained that hydraulic fracturing doesn’t produce as much waste fluid as do EORs and so may not have as big of an impact.
“The Oklahoma Geological Survey statement is more cautious about this,” Gilbert said. “They just aren’t sure yet whether this is a key part of the problem and how to hand it.”
One of the cases presented by Gilbert goes back from 1962-67 in Denver, Colo., referred to as the “Denver Arsenal,” a US Army facility where chemical weapons were made.
“They had a lot of waste and so they drilled a 12,000 foot well and started pumping the waste down in it,” Gilbert said. As a result, there was a series of earthquakes that began in the Denver area. “They quit pumping for a short time. The earthquakes went down. They started pumping again and the earthquakes went up, and so then they just quit pumping the stuff into the ground at all… They quit pumping because they realized, specifically in that case, that they were in fact causing earthquakes.”
Gilbert took several questions from the audience before concluding his presentation.
At the start of the Rotary Club Lunch, Rotarian Larry Duffy, with Rotary Club President Allen Sasse, recognized outgoing member Haley Thompson and welcomed new inductee Lora Lea Pickering. Pickering will be replacing Thompson as the Director of Development and Alumni Relations for WOSC.
“Before we welcome Lora Lea, let’s thank Haley for all of her good work in Rotary,” Duffy said. “Lora Lea comes to us with a lot of energy and a lot of interest in Western and we are pleased that she has accepted the invitation to be a member of our Rotary Club.”
Duffy then recognized member Henry Hartsell and presented the Paul Harris Fellow “Plus 6” for contributing $7,000 to the Rotary Foundation. “Henry is not only a long time member of Rotary, but he’s an avid supporter of the Rotary Foundation. He is a member of the Paul Harris Society,”Duffy said.