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Deep carbon cycling drives the splitting of the 520-km mantle discontinuity. [PDF]
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Geophysics, 1981
Abstract We exploit the differences that exist between the radiation fields of a point source and an array to design a time-separated marine seismic source array with desired power spectral and directional characteristics, whose far-field time signature is known precisely from measurements.The desired power spectral characteristics ...
Paul L. Stoffa, Anton L. Ziolkowski
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Abstract We exploit the differences that exist between the radiation fields of a point source and an array to design a time-separated marine seismic source array with desired power spectral and directional characteristics, whose far-field time signature is known precisely from measurements.The desired power spectral characteristics ...
Paul L. Stoffa, Anton L. Ziolkowski
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On the use of a seismic sensor as a seismic source
Geophysics, 2013ABSTRACT We investigated the use of seismic sensors as small seismic sources. A voltage signal is applied to a geophone that forces the mass within the geophone to move. The movement of the mass generates a seismic wavefield that was recorded with an array of geophones operating in the conventional sense. We observed higher-frequency (
Halliday, David F. +3 more
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The Journal of the Acoustical Society of America, 1981
An improved seismic prospecting system comprising the use of a closely spaced sequence of source initiations at essentially the same location to provide shorter objective-level wavelets than are obtainable with a single pulse. In a preferred form, three dynamite charges are detonated in the same or three closely spaced shot holes to generate a downward
Donald R. Hughes +2 more
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An improved seismic prospecting system comprising the use of a closely spaced sequence of source initiations at essentially the same location to provide shorter objective-level wavelets than are obtainable with a single pulse. In a preferred form, three dynamite charges are detonated in the same or three closely spaced shot holes to generate a downward
Donald R. Hughes +2 more
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Acta Seismologica Sinica, 2003
During the period of 1999~2002, the Chinese seismologists made a serious of developments in the study on seismic sources including observations, experiments and theory. In the field of observation, the methods of the accuracy location of earthquake sources, the inversion of seismic moment tensor and the mechanism of earthquake source are improved and ...
Li Shi-yu, Chen Yun-tai
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During the period of 1999~2002, the Chinese seismologists made a serious of developments in the study on seismic sources including observations, experiments and theory. In the field of observation, the methods of the accuracy location of earthquake sources, the inversion of seismic moment tensor and the mechanism of earthquake source are improved and ...
Li Shi-yu, Chen Yun-tai
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The Journal of the Acoustical Society of America, 1989
An impulsive seismic generator is mounted on a swamp buggy suitable for operations both in a marshy environment and on land. The generator employs a target plate which may be lowered into a body of water or mud beneath the buggy so as to contact subsurfaces of varying degrees of firmness.
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An impulsive seismic generator is mounted on a swamp buggy suitable for operations both in a marshy environment and on land. The generator employs a target plate which may be lowered into a body of water or mud beneath the buggy so as to contact subsurfaces of varying degrees of firmness.
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The Journal of the Acoustical Society of America, 1979
A seismic energy source which incorporates multiple augers and a rotary mechanism therefor mounted on a vehicle, the auger incorporating an internally situated seismic shock wave source which creates shock waves passing through a window in the auger into the soil.
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A seismic energy source which incorporates multiple augers and a rotary mechanism therefor mounted on a vehicle, the auger incorporating an internally situated seismic shock wave source which creates shock waves passing through a window in the auger into the soil.
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Geophysics, 1987
Abstract A prototype model of a downhole controlled seismic source has been built and field tested. This instrument is a swept-frequency, pneumatically powered seismic source that operates in the 10 to 100 Hz range. This particular version is a vertical-dipole source and generates vertically polarized shear waves. The instrument is an
H. C. Hardee +2 more
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Abstract A prototype model of a downhole controlled seismic source has been built and field tested. This instrument is a swept-frequency, pneumatically powered seismic source that operates in the 10 to 100 Hz range. This particular version is a vertical-dipole source and generates vertically polarized shear waves. The instrument is an
H. C. Hardee +2 more
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The Journal of the Acoustical Society of America, 1990
The improved seismic vibration apparatus (10) includes variable length control means (44) located so as to effectively and efficiently position the vibrator (36) relative to the base plate (30) and apparatus (40) to isolate the vibrator (36) from the control system (44) and from the vehicle frame (12) so that effective seismic vibration is imparted ...
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The improved seismic vibration apparatus (10) includes variable length control means (44) located so as to effectively and efficiently position the vibrator (36) relative to the base plate (30) and apparatus (40) to isolate the vibrator (36) from the control system (44) and from the vehicle frame (12) so that effective seismic vibration is imparted ...
openaire +1 more source