Digital Rocks Out to Become a Core Technology

Abstract

The future of oil and gas exploration depends on rocks such as carbonates and shale that can be described as tight, complex, nearly impermeable, and even stubborn. On the production side, the goal has long been to get more of the oil out of the ground, but recovery percentages have hardly budged. The search to better understand the inner workings of these rocks that challenge traditional laboratory testing has led to a new approach known as digital rock physics. It is a technological hybrid drawing on fields ranging from medical testing to microchip production. By marrying computerized tomography (CT) and other X-ray scanning technologies, pioneers in this emerging field are creating 3D images showing the internal structure—including pore spaces and how they connect—as well as the minerals and organic matter within. Digital rock physics providers promise faster, better, lower-cost analysis. The potential payoffs could include wells targeting the most productive rock, more effective well completions, and simulations speeding the development of enhanced oil recovery (EOR) techniques. The graphics are stunning. The attention to detail is exacting. But using imaging to directly measure reservoir properties is still a work in progress. Getting a clear look at the smallest details in some rocks requires scanning samples that are measured in microns. Finding ways to accurately scale up this data to provide telling details about a formation will define the future of this young business. The oldest of the three fast-growing companies selling digital rock physics services for exploration and production (E&P) goes back four years. Even the name “digital rock physics” is not set in stone. The growth in demand is in difficult formations such as shale and carbonates, and for simulating EOR projects that are hard to analyze using traditional means. Chevron, Shell, Statoil and Schlumberger are among the users. At Chevron Energy Technology Company, the digital rock work is led by Jairam Kamath, who organized a SPE forum to consider the future use of this technology. “The more you work with it, the more you are convinced,” he said. “It took me a couple years, but I am convinced this is how we will be doing business five or 10 years from now.” Shell is working with Schlumberger on a digital rocks project. It is one of many research projects at Shell seeking new ways to increase the output from aging fields. “I do believe there are large opportunities” there, said Gerald Schotman, chief technology officer of Shell. He described it as a way to deal with anomalies, when indicators such as the production history are out of line with predictions by the reservoir model.