Print this pageThe Use of Passive 
Seismic
Monitoring for the Exploration and
Production of Hydrocarbon Reservoirs
The use of passive seismic energy to help understand the
static and dynamic nature of the subsurface is rapidly gaining industry
interest. These naturally occurring sources can provide a wealth of information
regarding larger scale structural features, as well as reservoir scale
production or injection induced changes in fluid and rock properties.
Two applications are being progressed that exploit passive seismic on
differing scales. Transmission Tomography utilizes local micro-earthquakes as
seismic source to create three-dimensional P and S wave velocity volumes, from
which structure, faulting and lithology
can be inferred. The environmentally benign acquisition methods make
Transmission Tomography ideally suited for many exploration applications in the
Monitoring the release of micro-seismic energy associated
with reservoir level production activities is becoming a well established
technique for understanding several dynamic reservoir processes. Two different
methods are being commercially progressed, downhole
and surface monitoring. Downhole observation utilizes
a linear array of geophones placed in a wellbore to
detect and locate the hypo-centers of discrete micro-seismic events. Surface monitoring ‘beam-steers' the output from a relatively dense
surface array to identify the location of both continuous and transient
acoustic sources without requiring the detection of discrete events.
Both methods allow the operator to relate micro-seismic
events to the
progression of dynamic reservoir processes such as hydraulically stimulated
fracture growth, injected fluid movement, reservoir compaction, reactivated
fault movement and compartmentalization.