Ground Motion Microseismic Observation
Microseismic monitoring is a technology that detects and records microseismic activities of the Earth’s subsurface. The technique provides direct insight into the mechanical behavior of a rock mass, thus enabling detailed characterization of the subsurface. As a foundation for geotechnical and geoscientific research, microseismic monitoring has been used to improve management of challenges, from reservoir monitoring to disaster management.
The primary concept underlying microseismic monitoring is that when any seismic energy is released from a source in the Earth’s subsurface, such as an induced fracture, fault slip, reservoir depletion, or settling of a rock mass, the energy is radiated in all directions and can be detected at the surface or in boreholes. Through the use of sensitive modern instrumentation, a variety of ground motion parameters, such as peak particle velocity, frequency content, and displacement, can be measured and used to distinguish between different types of seismicity, as well as to track changes in the Earth’s subsurface.
Microseismic monitoring has been used in a variety of applications that have both academic and commercial value. In a geotechnical application, microseismic monitoring can be used to detect and record subsurface conditions in unstable slopes, deep excavations, or other areas where the subsurface is subject to significant stress. The collected data can then be used to gain a better understanding of the stability of the rock mass, allowing engineers to identify areas of potential weakness or risk that may require further investigation. In a commercial application, microseismic monitoring can be used to monitor the production of an oil or gas field, for example, by tracking the number and location of new microseismic activity in order to optimize the production process.
In addition to its use for geotechnical and commercial concerns, microseismic monitoring has also been employed for disaster management. In the event of an earthquake or landslide, microseismic monitoring can be used to quickly identify areas of potential danger and alert authorities to the location of the event. Such information can then be used to direct medical and rescue personnel to affected areas in order to quickly respond to the event.
Microseismic monitoring can provide a wealth of data that can be used to forewarn of hazardous situations and to aid in emergency response. It also provides valuable insight into the Earth’s subsurface, which can be used for geotechnical research and improved engineering decisions. Such insight can lead to a safer, more secure, and more efficient environment for all of us.
