Patent application number | Description | Published |
20090034365 | Determining Seawater Conductivity for the Compensation of Electromagnetics-Based Survey Data - A technique includes obtaining seismic data, which was acquired during a seismic survey in seawater. The technique includes based on the seismic data, determining a conductivity of the seawater and processing data obtained from an electromagnetics-based survey based on the determined conductivity. | 02-05-2009 |
20100103774 | VSP IMAGING OF ACOUSTIC INTERFACES - A method to generate images of acoustic contrasts for structures located between at least one acoustic source and at least one receiver, said structures converting a part of the compressional energy to shear. | 04-29-2010 |
20110267922 | MECHANICAL TUBE WAVE SOURCES AND METHODS OF USE FOR LIQUID FILLED BOREHOLES - The current application discloses methods and systems for generating mechanical tube waves in fluid filled boreholes penetrating subterranean formations. In one embodiment, the system of the current application comprises an energy storage chamber; a fast operating valve connected to the energy storage chamber; a pipe connected to the valve and extending to the liquid-filled borehole; where said energy storage chamber contains a first pressure that is substantially different from a second pressure in the pipe so that a fast operation of the valve generates a tube wave in the pipe. | 11-03-2011 |
20110292763 | DETECTION OF SEISMIC SIGNALS USING FIBER OPTIC DISTRIBUTED SENSORS - A fiber optic distributed vibration system for detecting seismic signals in an earth formation is provided. The system includes a fiber optic cable deployed in a borehole that extends into the earth formation and which is configured to react along its length to a seismic wave incident on the fiber optic cable from outside the borehole. An optical source launches an optical signal into the fiber optic cable while the seismic wave is incident thereon. A receiver detects coherent Rayleigh noise (CRN) produced in response to the optical signal. A processing circuit processes the detected CRN signal to determine characteristics of the earth formation. | 12-01-2011 |
20120298421 | DETECTION OF GAS INFLUX INTO A WELLBORE - An influx of gas into a borehole can be detected by deploying a string of acoustic sensors along a drill string or other conduit to monitor an acoustic characteristic, such as velocity or attenuation, of the drilling fluid present in the borehole. In response to detection of acoustic pulses propagating in the drilling fluid, the acoustic sensors generate signals that are representative of acoustic characteristics if the drilling fluid. Based on the generated signals, a data acquisition system can determine whether a change in the monitored acoustic characteristic is indicative of a gas influx. | 11-29-2012 |
Patent application number | Description | Published |
20080236935 | DETERMINATION OF DOWNHOLE PRESSURE WHILE PUMPING - Tubewaves are used to transmit an indication of the depth at which a condition is detected in a well. In particular, the depth is calculated based on the difference in arrival time at the surface of a first tubewave which propagates directly upward in the borehole and a second tubewave which initially travels downward and is then reflected upward. The tubewaves may be generated by a canister designed to implode at a certain pressure. After being introduced into the flowline at an above ground inlet, the canister is carried downhole by gravity and the fluid being pumped. When the canister reaches a depth at which its pressure tolerance is exceeded, it implodes and generates the tubewaves. An analyzer at the surface detects the tubewaves with a hydrophone array and generates a pressure versus depth profile of the well, i.e., one data point for each implosion. Canisters may be acoustically tagged by controlling volume and orifice size in order to generate tubewaves having particular frequency and amplitude characteristics. Canisters may also be configured to produce multiple implosions, e.g., one implosion at each of a selection of different pressures. Canisters may also be equipped with triggering and arming mechanisms, and may generate tubewaves in response to conditions other than a particular pressure. | 10-02-2008 |
20080239872 | Wireless Logging of Fluid Filled Boreholes - A predetermined condition in a fluid-filled wellbore system can be detected by generating at least one sound in the wellbore system in response to the condition, such that a detectable change is created in some characteristic of the emitted sound, and detecting the at least one sound and the change, the detection being indicative that the predetermined condition has occurred. Equipment for facilitating detection of the condition can include a trigger operable in response to the condition; a generator operable to emit sound in the borehole and to create a detectable change in some characteristic of the emitted sound in response to the trigger; and at least one sensor operable to monitor the sound and detect the change, the detection being indicative that the predetermined condition has occurred. It is also possible to estimate a value of a property of a fluid-filled wellbore system. This can be accomplished by recording data including at least one of pressure and rate of flow at one or more locations in the wellbore system, and then estimating the value of the property by employing a model for predicting at least one of pressure and rate of flow dependent upon parameters detailing at least one of wellbore system geometry, viscoacoustic properties of the fluid and entrained solids contained in the wellbore system, locations of boundaries and entrained solids, and characteristics and locations of disturbances to pressure and flow in the wellbore system, in order to determine a best prediction of some attribute of the recorded data. | 10-02-2008 |
20090097356 | PROCESSING OF COMBINED SURFACE AND BOREHOLE SEISMIC DATA - Methods and related systems are described for processing surface seismic data. Surface seismic data representing seismic signals detected at a plurality of surface locations is wavefield deconvolved using a combination of direct wave travel times estimated from borehole seismic data, and wavefield energy estimated from the surface seismic data. | 04-16-2009 |
20090236145 | ANALYSIS REFRACTED ACOUSTIC WAVES MEASURED IN A BOREHOLE - Methods and related systems are described for measuring and analyzing refracted acoustic energy. A plurality of receivers mounted are on a downhole tool, and are arranged and adapted to receive refracted acoustic energy from a downhole formation. Measurements of refracted acoustic energy is analyzed such that information relating to an azimuthal direction relative to the downhole tool of an interface within the downhole formation can be estimated. The receivers can be mounted on a drill collar as part of a LWD tool and steering of the drilling trajectory can be based in part on the estimated formation information. | 09-24-2009 |