Abstract:
One embodiment of the present disclosure includes a method for processing seismic data comprising the steps of receiving data representing seismic energy gathered from a formation by a plurality of seismic receivers, wherein the data include primary and multiple data. A copy of the received data is created and compensated to reduce amplitude attenuation effects due to transmission and absorption losses. A multiple prediction algorithm is applied to the received and compensated data to obtain a multiple data prediction. The multiple data prediction is subtracted from the received data to obtain primary data. The primary data is processed to reduce attenuation effects in the received data.
Abstract:
A method includes receiving a seismic dataset from a survey, wherein the seismic dataset represents a portion of a subsurface geological formation and includes primary and multiple data. The method further includes the steps of conditioning the seismic dataset and estimating a model of the multiple data in the conditioned seismic dataset based on a user-defined parameter to derive a primary data set. Further, the method includes the steps of computing a velocity model from the primary data set using the user-defined parameter and updating the estimated multiple model based at least on a modification of the user-defined parameter. In addition, the method includes the steps of recomputing the primary data and the velocity model based on the modified user-defined parameter and generating an image of the primary data.
Abstract:
A technique generates seismic data that may be analyzed. A combination sensor is operated and deployed in a borehole to obtain orientation data, such as data related to the local magnetic field and a log of the magnetic field direction in the borehole. Following the combination sensor, at least one multi-component seismic source is deployed downhole into the borehole. The at least one multi-component seismic source comprises sensors, such as an inclinometer and a magnetometer. Data from the combination sensor and from the at least one multi-component seismic source is processed to determine an absolute orientation of the at least one multi-component seismic source.
Abstract:
A method includes receiving a seismic dataset from a survey, wherein the seismic dataset represents a portion of a subsurface geological formation and includes primary and multiple data. The method further includes the steps of conditioning the seismic dataset and estimating a model of the multiple data in the conditioned seismic dataset based on a user-defined parameter to derive a primary data set. Further, the method includes the steps of computing a velocity model from the primary data set using the user-defined parameter and updating the estimated multiple model based at least on a modification of the user-defined parameter. In addition, the method includes the steps of recomputing the primary data and the velocity model based on the modified user-defined parameter and generating an image of the primary data.
Abstract:
A well-logging tool includes a magnetic field logging tool and a borehole seismic array, which includes a plurality of seismic sensor devices coupled together in series. Each seismic sensor device includes a sensor housing and at least one seismic sensor carried by the sensor housing. A magnetometer is carried by the sensor housing to sense the local magnetic field. A controller cooperates with the magnetic field logging tool to generate a log of the local magnetic field relative to the true earth geographic pole. The controller cooperates with the borehole seismic array to determine an orientation of each seismic sensor device based upon the respective sensed local magnetic field and log of the local magnetic field relative to the earth geographic pole.
Abstract:
A technique generates seismic data that may be analyzed. A combination sensor is operated and deployed in a borehole to obtain orientation data, such as data related to the local magnetic field and a log of the magnetic field direction in the borehole. Following the combination sensor, at least one multi-component seismic source is deployed downhole into the borehole. The at least one multi-component seismic source comprises sensors, such as an inclinometer and a magnetometer. Data from the combination sensor and from the at least one multi-component seismic source is processed to determine an absolute orientation of the at least one multi-component seismic source.
Abstract:
A well-logging tool includes a magnetic field logging tool and a borehole seismic array, which includes a plurality of seismic sensor devices coupled together in series. Each seismic sensor device includes a sensor housing and at least one seismic sensor carried by the sensor housing. A magnetometer is carried by the sensor housing to sense the local magnetic field. A controller cooperates with the magnetic field logging tool to generate a log of the local magnetic field relative to the true earth geographic pole. The controller cooperates with the borehole seismic array to determine an orientation of each seismic sensor device based upon the respective sensed local magnetic field and log of the local magnetic field relative to the earth geographic pole.
Abstract:
Neutrally-buoyant tools for seismic data collection are provided that may range from several hundred meters to several kilometers in length and have integrated sensors which move along with the borehole fluid in response to a passing seismic wave. The disclosure also provides methods of deploying neutrally-buoyant tools, which includes using a tractor, adding a weight or both to the tool in order to overcome the difficulty of lowering a neutrally buoyant tool into a borehole, and optionally occasionally clamping the tool to the borehole to alleviate tension in the tool. This disclosure also provides methods of acquiring seismic data, which involves positioning a neutrally-buoyant tool in a borehole such that the tool is able to move relatively freely along with the borehole fluid in response to a seismic wave passing through the fluid, firing a seismic source, and using the sensors to collect seismic data generated thereby.
Abstract:
The disclosure provides neutrally-buoyant tools for seismic data collection. The tools may range from several hundred meters to several kilometers in length and have integrated sensors which move along with the borehole fluid in response to a passing seismic wave. The disclosure also provides methods of deploying neutrally-buoyant tools, which includes using a tractor, adding a weight or both to the tool in order to overcome the difficulty of lowering a neutrally buoyant tool into a borehole, and optionally occasionally clamping the tool to the borehole to alleviate tension in the tool. This disclosure also provides methods of acquiring seismic data, which involves positioning a neutrally-buoyant tool in a borehole such that the tool is able to move relatively freely along with the borehole fluid in response to a seismic wave passing through the fluid, firing a seismic source, and using the sensors to collect seismic data generated thereby.
Abstract:
The disclosure provides a borehole tool for seismic data collection. The tool comprises a cable to be positioned within a borehole and at least one sensor for measuring seismic signals mounted on the cable. The sensors provide measurements of particle motion (velocity or acceleration) perpendicular to an axis of the borehole. The disclosure also provides methods of seismic surveying, which involves positioning the tool in the borehole, firing a seismic source generating a seismic wave and measuring particle motion associated with the passing seismic wave perpendicular to an axis of the borehole using the at least one sensor for measuring particle motion.