Distributed Acoustic Sensing Monitoring at the First EGS Collab Testbed

Session: Photonic Seismology
Type: Oral
Date: 4/30/2020
Time: 08:45 AM
Room: 215 + 220
Description: 

The EGS Collab project is conducting small-scale underground studies on fracture stimulation and monitoring for enhanced geothermal system (EGS) development. The first testbed is located at a depth of 4850 ft below the surface at the Sanford Underground Research Facility in South Dakota. The testbed consists of a stimulation well, a production well and six monitoring wells around a 10-m fracture stimulation zone. A length of optical fiber was deployed in the six monitoring wells to continuously collect distributed acoustic sensing (DAS) data during hydraulic stimulations. The total length of the fiber is around 1600 m and the channel spacing is 1 m. The gauge length is 10 m. During the course of monitoring, the DAS data were collected at either a 1 kHz or a 10 kHz sampling frequency. We analyze and process the 10 kHz DAS data to compare the data before, during and after hydraulic stimulations. We also compare the DAS data to data collected by hydrophones and three component accelerometers deployed in the monitoring wells to study the feasibility of DAS for monitoring hydraulic fracturing in EGS reservoirs.

Presenting Author: David Li

Authors