In a May 30 press release Schlumberger said its microseismic monitoring “provides direct 4-D information about stress changes in a reservoir by recording seismic waves generated during very small slip events.”
Relatively new to the oil and gas industry, the technology can “map the path of fractures from the wellbore into the reservoir as they are created by hydraulic stimulations. When used with recently developed real-time monitoring technology, microseismic information helps engineers optimize production and mitigate risk throughout the life of the field by optimizing hydraulic fracturing jobs on the fly,” Schlumberger said.
Previously, microseismic data from a produced or stimulated well was acquired using a tool positioned in a separate well often drilled for that purpose. Today, “an innovative technology that reduces noise associated with fluid flow allows this data to be obtained in active treatment or production wells,” the company said.
Used with the PS3 passive seismic sensing system, the Omega-Lok device couples geophones to the inside of casing as part of the well completion. It also decouples the sensors from the tubing, “minimizing completion noise passively while maximizing formation coupling.
A hydraulically activated release mechanism is used to deploy the fit-for-purpose, low-noise-floor sensors,” reducing the noise by a factor of 100 compared with other tubing-conveyed monitoring methods, enabling “long-term monitoring without the cost of drilling offset monitor wells and exploits the full value of microseismic information on a reservoir-wide scale,” Schlumberger said.