Permanently installed in-well fiber optic accelerometer-based seismic sensing apparatus and associated method
AssigneeWeatherford/Lamb, Inc.
InventorFrancis X. Bostick, III
Life of this patent
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Abstract
Embodiments of the present invention include a fiber optic seismic sensing system for permanent downhole installation. In one aspect, the present invention includes a multi-station, multi-component system for conducting seismic reservoir imaging and monitoring in a well. Permanent seismic surveys may be conducted with embodiments of the present invention, including time-lapse (4D) vertical seismic profiling (VSP) and extended micro-seismic monitoring. Embodiments of the present invention provide the ability to map fluid contacts in the reservoir using 4D VSP and to correlate micro-seismic events to gas injection and production activity.
Claims28
A method for seismically surveying a formation around a wellbore, comprising:
- lowering one or more seismic stations into the wellbore, each seismic station comprising optically based seismic sensors, at least three of the sensors arranged to sense in axes approximately orthogonally positioned;
- coupling the sensors to the formation;
- and
- detecting one or more seismic events at each of the sensors,
- wherein the one or more seismic stations comprise a plurality of seismic stations, each seismic station comprising optically based seismic sensors, at least three of the sensors arranged to sense in axes approximately orthogonally to each other,
- wherein one or more of the plurality of seismic stations is disposed nearer to a reservoir of the formation than a remainder of the plurality of seismic stations in order to perform micro-seismic monitoring.
A method for seismically surveying a formation around a wellbore, comprising:
- lowering one or more seismic stations into the wellbore, each seismic station comprising optically based seismic sensors, at least three of the sensors arranged to sense in axes approximately orthogonally positioned;
- lowering one or more optically based hydrophones into the wellbore;
- coupling the sensors and the one or more optically based hydrophones to the formation;
- and
- detecting one or more seismic events at each of the sensors and the one or more hydrophones, wherein the one or more seismic events include one or more microseismic events.
The method of clam 21, further comprising comparing the image of the formation obtained by the one or more hydrophones to the image of the formation obtained by the sensors to account for mechanical resonance of the sensors.
A seismic sensing system, comprising:
- a plurality of seismic stations disposed in a wellbore, each seismic station comprising optically based seismic sensors, at least three of the sensors arranged to sense in axes approximately orthogonally positioned and coupled to the formation, wherein one of the plurality of seismic stations is disposed nearer to a reservoir of the formation than a remainder of the plurality of seismic stations in order to conduct micro-seismic monitoring;
- and
- seismic processing equipment coupled to the one or more seismic stations by one or more optical waveguides and configured to detect one or more seismic events at each of the sensors.
Dependencies are inferred from the claim text.