What is geophone in seismic?
A geophone is a device that converts ground movement (velocity) into voltage, which may be recorded at a recording station. The deviation of this measured voltage from the base line is called the seismic response and is analyzed for structure of the earth.
What is the difference between geophone and hydrophone?
Geophones are sensitive to the direction of particle motion for the seismic wave, but hydrophones are omnidirectional. Our experience indicates that downhole geophones, such as the SIE Geosource tool, are more sensitive than hydro- phones, such as those in our downhole streamers.
What is the difference between a geophone and a seismometer?
Broadband seismometers are high performing instruments rooted in earthquake seismology, whereas geophones are traditionally used in large quantities for active seismic surveys in exploration applications.
What is a geophone string?
Geophone Strings SM-6 The SM-6, made by SENSOR Nederland, is a vertical geophone in a PE-5 case, and with a 75 mm steel spike. The geophone string consists of six geophones spacing 10 metres each, with a lead-in of two metres, and terminated with a PE-7 multiple string connector with wide and narrow clips.
What is natural frequency of geophone?
The sensitivity of this geophone reaches 100 V/m/s (see Fig. 9.2B). Its nature frequency is 14 Hz, and the approximate usable frequency response varies from 7 to 2000 Hz.
What is hydrophone mean?
A hydrophone is an underwater device that detects and records ocean sounds from all directions. People often think that the underwater world is silent. In fact, numerous marine organisms use sound for communication, reproduction, and to seek prey.
How is a geophone used?
Geophones—also called jugs, pickups, and tortugas—are placed on the ground surface in various patterns, or arrays, to record the vibrations generated by explosives in seismic reflection and refraction work. They also are used as military detection devices.
How much does a geophone cost?
Geophones used in exploration seismology are relatively inexpensive. Costs ranging from $75 to $150 per geophone are not uncommon. Although this cost per geophone is small, remember that many (1000’s) of geophones may be used in the large reflection seismic surveys conducted for the petroleum industry.
What is seismic refraction method?
Seismic Refraction (SR) is a surface geophysics method that utilizes the refraction of seismic waves on geology layers and rock/soil units to characterize subsurface geologic conditions.
What is the spurious frequency of a geophone?
An important feature of geophones is that they can only monitor frequencies above their natural frequency, up to a specified spurious frequency. A natural frequency on the order of 10 Hz, and a spurious frequency on the order of 250 Hz are common.