An air gun for generating seismic waves in a marine environment includes a cylindrical body configured to hold compressed air and having plural air ports for releasing the compressed air from inside the cylindrical body, the cylindrical body extending along a longitudinal axis X, and an extension member attached externally to the body and extending along a radial axis R, which is perpendicular to the longitudinal axis X. The extension member promotes ambient water flowing inside an air bubble generated when the compressed air is released outside the body.

An air gun for generating seismic waves in a marine environment includes a cylindrical body configured to hold compressed air and having plural air ports for releasing the compressed air from inside the cylindrical body, the cylindrical body extending along a longitudinal axis X, and an extension member attached externally to the body and extending along a radial axis R, which is perpendicular to the longitudinal axis X. The extension member promotes ambient water flowing inside an air bubble generated when the compressed air is released outside the body.

A seismic marine vibrator (100) may comprises first plates (102) and second plates (104) arranged along a longitudinal axis (101), longitudinal and peripheral first (106) and second (108) elements respectively secured to the first (102) and second (104) plates, and an actuator (112) operable to reciprocate the first elements (106) relative to the second elements (108) along the longitudinal axis (101) so as to reciprocate the first plates (102) relative to the second plates (104). The seismic marine vibrator further comprises peripherally closed air-filled chambers (109) and peripherally open chambers (111), the volume of said open chambers (111) being varied when the first plates (102) are reciprocated so as to take in and expel water radially to generate an acoustic wave. This forms an improved seismic marine vibrator.

The embodiments herein describe a seismic source that includes at least two firing heads connected to a shared reservoir of compressed gas. When underwater, a controller can instruct the firing heads to fire at the same time or at different times to create gas bubbles that generate seismic energy for identifying structures underneath a body of water. If the firing heads fire at the same, the resulting gas bubble may coalesce to form a single bubble, depending on the size of the respective bubbles and the separation distance between the firing heads. In one embodiment, the firing heads are attached at opposite ends of the shared reservoir (although this is not a requirement). The length of the reservoir, which dictates in part the separation distance of the firing heads, can be set so that gas bubbles generated by the firing heads at substantially the same time coalesce.

The embodiments herein describe a seismic source that includes at least two firing heads connected to a shared reservoir of compressed gas. When underwater, a controller can instruct the firing heads to fire at the same time or at different times to create gas bubbles that generate seismic energy for identifying structures underneath a body of water. If the firing heads fire at the same, the resulting gas bubble may coalesce to form a single bubble, depending on the size of the respective bubbles and the separation distance between the firing heads. In one embodiment, the firing heads are attached at opposite ends of the shared reservoir (although this is not a requirement). The length of the reservoir, which dictates in part the separation distance of the firing heads, can be set so that gas bubbles generated by the firing heads at substantially the same time coalesce.

A marine vibrator may include a containment housing, a sound radiating surface, and a compliance chamber. The compliance chamber may include a compliance chamber housing, a non-linear linkage assembly, and a low pressure chamber. The compliance chamber housing may define at least a portion of a compliance chamber internal volume having a compliance chamber internal gas pressure. The low pressure chamber may comprise a low pressure piston and a low pressure chamber housing. The low pressure chamber housing may define at least a portion of a low pressure chamber internal volume having a low pressure chamber internal gas pressure. The low pressure piston may be configured to move in response to a pressure differential across the low pressure piston such that a resonance frequency of the marine vibrator may be changed.

A marine vibrator may include a containment housing, a sound radiating surface, and a compliance chamber. The compliance chamber may include a compliance chamber housing, a non-linear linkage assembly, and a low pressure chamber. The compliance chamber housing may define at least a portion of a compliance chamber internal volume having a compliance chamber internal gas pressure. The low pressure chamber may comprise a low pressure piston and a low pressure chamber housing. The low pressure chamber housing may define at least a portion of a low pressure chamber internal volume having a low pressure chamber internal gas pressure. The low pressure piston may be configured to move in response to a pressure differential across the low pressure piston such that a resonance frequency of the marine vibrator may be changed.

Acoustic data can be collected from oil wells having various configurations of tubing and casing and under various operational conditions such as pumping, shut-in, and transition phases such as pressure build up. The acoustic data is collected by a microphone in response to the generation of an acoustic pulse that is transmitted into the well. There is typically substantial noise in the well pipes and this noise can degrade the quality of the reflected data recorded from the acoustic pulse. Much of this noise is produced by the flow of gas in the tubing and associated flow lines. Apparatus for use with the well can be configured to control the state of certain valves which can lead to a reduction of the noise received for the microphone that records the acoustic data.

Acoustic data can be collected from oil wells having various configurations of tubing and casing and under various operational conditions such as pumping, shut-in, and transition phases such as pressure build up. The acoustic data is collected by a microphone in response to the generation of an acoustic pulse that is transmitted into the well. There is typically substantial noise in the well pipes and this noise can degrade the quality of the reflected data recorded from the acoustic pulse. Much of this noise is produced by the flow of gas in the tubing and associated flow lines. Apparatus for use with the well can be configured to control the state of certain valves which can lead to a reduction of the noise received for the microphone that records the acoustic data.

A method for 2D seismic data acquisition includes determining source-point seismic survey positions for a combined deep profile seismic data acquisition with a shallow profile seismic data acquisition wherein the source-point positions are based on non-uniform optimal sampling. A seismic data set is acquired with a first set of air-guns optimized for a deep-data seismic profile and the data set is acquired with a second set of air-guns optimized for a shallow-data seismic profile. The data are de-blended to obtain a deep 2D seismic dataset and a shallow 2D seismic dataset.