Technology Focus: Hydraulic Fracturing (March 2012)

Abstract

Technology Focus Hydraulic Fracturing: 2012 and Beyond It is a good time to be in the oil industry. The rig count, drilling activity, and oil prices are high, and shale plays are a significant reason for each. And, because it is shale, it is an especially good time to be a completion engineer! Even though we have been able to make these unconventional reservoirs economic by drilling horizontal wells and by multistage fracturing, it is important for us to realize (especially with low gas prices) that there is still plenty to learn about shale fracing (not spelled “fracking”). Buzz words fly around the industry: complex fractures, brittle vs. ductile shale, proppant transport in slickwater, and more. Each is a start, but what I challenge everyone to do is to ask the questions: What is really happening when we are fracturing the various shale plays; and how do we model it so that we can predict and optimize performance? Economic and political implications of shale are enormous. The USA recently, for the first time in many years, became a net exporter of energy. The USA has clear shale-development advantages compared with other countries at this time because it has the rigs, hydraulic horsepower, personnel, and a long history of hydraulic fracturing. But truth be told, there are disadvantages that must be dealt with. The USA is dealing with an oversupply of gas, which is reducing prices and making shale-gas plays marginally economical. To date, despite industry efforts, there still is no political will to substitute fuel sources on a large scale, create a widespread gas-fueling infrastructure, or increase automobile shale-gas usage appreciably. So even though it is a good time to be in the oil field, remember that as completion engineers it is our job/duty to understand what is happening downhole when we are fracturing—Do we really have complexity? Does complexity occur in every shale interval or just the brittle ones? Does proppant “turn the corner” and go into the natural fractures? Knowing the answers to these and other questions can make the economics of shale plays become even better. Recommended additional reading at OnePetro: www.onepetro.org. SPE 147652 An Experimental Investigation of Spontaneous Imbibition in Gas Shales by B. Roychaudhuri, University of Southern California, et al. SPE 139984 Hydraulic Fracture Crossing a Natural Fracture at Nonorthogonal Angles: A Criterion, Its Validation, and Applications by H. Gu, University of Ganguly, et al. SPE 147248 Revisiting Microfrac In-Situ-Stress Measurement Through Flowback—A New Protocol by Alexei A. Savitski, SPE, Shell, et al.