Practical solutions for effective vibrator high-frequency generation

Tellier, Nicolas; Caradec, G.; Ollivrin, Gilles

doi:10.1190/segam2015-5844765.1

Cited by 4 publications

(5 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Despite the ease with which the ground‐force estimate can be recorded, the convention for Vibroseis data is still to correlate the data with the synthetic pilot. Although improvements in the accuracy of the ground‐force measurement have been claimed through the use of stiffer baseplates and more careful accelerometer placement (Wei ; Tellier, Caradec and Ollivrin ) measurements with thin‐film pressure pads suggest that the transmitted signal is too complex for a single accelerometer to measure (Dean et al . ).…”

Section: Data Processingmentioning

confidence: 99%

“…Despite the ease with which the ground-force estimate can be recorded, the convention for Vibroseis data is still to correlate the data with the synthetic pilot. Although improvements in the accuracy of the ground-force measurement have been claimed through the use of stiffer baseplates and more careful accelerometer placement (Wei 2009;Tellier, Caradec and Ollivrin 2015) measurements with thinfilm pressure pads suggest that the transmitted signal is too complex for a single accelerometer to measure (Dean et al 2015). In particular, the ground-force signal tends to have a much higher harmonic noise content than the geophone measurements (Saragiotis, Scholtz and Bagaini 2010) resulting in the harmonic noise level of the data being over-estimated resulting in additional noise contamination.…”

Section: A T a P R O C E S S I N Gmentioning

confidence: 99%

See 1 more Smart Citation

The construction of a simple portable electromagnetic vibrator from commercially available components

Dean

Nguyễn

Kepic

et al. 2018

Geophysical Prospecting

View full text Add to dashboard Cite

Since its introduction in the late 1950s, hydraulic vibrators have become the dominant source for land seismic surveys. The hydraulic vibrators typically used for commercial land seismic acquisition, however, are large, costly to operate and expensive to purchase. This inhibits their use for small‐scale and short‐duration surveys as well as Vibroseis research. In this paper we describe, in detail, the construction of a portable vibrator from commercially available components for a cost of less than $US2,000. Data shows that the vibrator is able to successfully transmit sweeps from 15 to 180 Hz with different spectral contents. The vibrator produces a stronger signal than a sledgehammer and we estimate its output to be around 1 kN. The frequency content of the data was concentrated at lower frequencies (<100 Hz) and the ground‐roll was far more energetic than that produced using a sledgehammer.

show abstract

Section: Data Processingmentioning

confidence: 99%

Section: A T a P R O C E S S I N Gmentioning

confidence: 99%

The construction of a simple portable electromagnetic vibrator from commercially available components

Dean

Nguyễn

Kepic

et al. 2018

Geophysical Prospecting

View full text Add to dashboard Cite

show abstract

“…At the high end of the spectrum (from about 80 up to 250 Hz), vibrators still face mechanical and hydraulic problems related to the rigidity of their baseplate, the ground behaviour, and the response of the valves at high frequency (Wei and Phillips ). These limitations may be mitigated using properly designed vibrators with stable hydraulic pressure and more rigid baseplate (Tellier, Caradec and Ollivrin ). However, above ∼80 Hz (depending on ground conditions), there is a phase shift, increasing with frequency, between the reaction mass and the baseplate.…”

Section: Land Equipment For Broadband Seismic: the Source Sidementioning

confidence: 99%

“…properly designed vibrators with stable hydraulic pressure and more rigid baseplate (Tellier, Caradec and Ollivrin 2015a). However, above ß80 Hz (depending on ground conditions), there is a phase shift, increasing with frequency, between the reaction mass and the baseplate.…”

Section: Figurementioning

confidence: 99%

“…More often than not, this is not enough to record high-frequency reflections due to their strong absorption during propagation. Such attenuation may be compensated using high-dwell sweeps (or logarithmic sweeps) where the time spent increases with frequency (Tellier et al 2015a). However, field tests showed that, except for sensors in a borehole, it is still difficult to recover high frequencies above 80 or 120 Hz depending on ground conditions (Mougenot and Meunier 2002).…”

Section: Figurementioning

confidence: 99%

See 1 more Smart Citation

Marine, seabed, and land seismic equipment for broadband acquisition: a review

Mougenot¹

2017

Geophysical Prospecting

View full text Add to dashboard Cite

The broadband capabilities of marine, seabed, and land seismic equipment are reviewed with respect to both the source and the receiver sides. In marine acquisition, the main issue at both ends of the spectrum relates to ghosts occurring at the sea surface. Broadband deghosting requires towing at variable depth to introduce notch diversity or using new equipment like multi‐component and/or low‐noise streamers. As a result, a doubling of the bandwidth from about three to six octaves (2.5–200 Hz) has been achieved. Such improvement is not yet observed for seabed surveys in spite of deghosting being a standard process on the receiver side. One issue may be related to the coupling of the particle motion sensor, particularly at high frequencies. For land acquisition, progress came from the vibrators. New shakers and control electronics using broadband sweeps made it possible to add two more octaves to the low‐frequency signal (from 8 to 2 Hz). Whereas conventional 10 Hz geophones are still able to record such low frequencies, 5 Hz high gain geophones or digital accelerometers enhance them to keep the signal above the noise floor. On the high end of the bandwidth, progress is not limited by equipment specifications. Here, the issue is related to a low signal‐to‐noise ratio due to the strong absorption that occurs during signal propagation. To succeed in enlarging the bandwidth, these improved equipment and sweeps must be complemented by a denser spatial sampling of the wavefield by point–source and point–receiver acquisition.

show abstract

SmartLF for robust and straightforward reduction of low-frequency distortion

Ollivrin¹,

Tellier²

2019

SEG Technical Program Expanded Abstracts 2019

View full text Add to dashboard Cite

Practical solutions for effective vibrator high-frequency generation

Cited by 4 publications

References 8 publications

The construction of a simple portable electromagnetic vibrator from commercially available components

The construction of a simple portable electromagnetic vibrator from commercially available components

Marine, seabed, and land seismic equipment for broadband acquisition: a review

SmartLF for robust and straightforward reduction of low-frequency distortion

Contact Info

Product

Resources

About