Tech provider explains merits of microseismic for shale plays

By Luke Geiver | November 20, 2013

North Dakota currently has four buried microseismic arrays used to monitor and optimize hydraulic fracturing. Cherie Telker, geology team leader for Microseismic Inc., a Houston-based microseismic technology provider, recently spoke on a webinar, “The Variable Nature of Shale Plays: How Monitoring Can Help,” explaining why North Dakota or other regions with shale energy development, can benefit from more microseismic monitoring. The technology, Telker said, “helps customers understand how the reservoir reacts to stimulation and helps operators improve their completions and create field development plans.”

The technology can monitor subsurface geologic activity while also providing visual representation of a completed frack job. To date, Microseismic has monitored over 20,000 fracture stages. According to Telker, oil retrieval has changed since the advent of hydraulic fracturing and its ability to capture unconventional oil. In the conventional oil retrieval industry, there are source rocks responsible for producing or pushing oil into reservoir traps or seals. Traditionally, those traps or seals were the targets of vertical wells. Today, however, shale rock is now considered the reservoir and geologists are less concerned with traps or seals.

Unconventional oil resources are difficult to assess, she also said. An operator must plan carefully for placing a lateral, the length of the lateral and how many stages can be profitably stimulated. “Predicting the details of variability is impractical,” she explained. “It is better to monitor and measure success.”

Mike Mueller, vice president of technology development for the company, said the concept of monitoring every fracture through the use of microseismic helps to manage the variability present in shale plays. The challenge of such plays, he added, is to drill thousands of wells on thousands of pads but not suffer diminished returns on the massive capital deployed. The major benefit of monitoring every frack, he explained, is to allow operators to assess the success of a well in real-time and replan or redevelop a well or field based on the real-time data. In some instances that might mean keeping a completions team in an area longer or rethinking the sequence for which wells will be completed or new wells will be drilled.

The Microseismic approach to monitoring places two to three buried grid points per square mile. Those grid points can monitor hundreds of wells through a large operator acreage position. In addition to allowing operators to assess success and plan for future development, the monitoring also helps them better understand the well depletion process.