GEOPHONES
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!GEOPHONE STRINGS ATTACHED TO SNOW STREAMER
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!!String specifications
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Each string attached to the snow streamer consists of 8 ea series connected gimbal suspended geophones.
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(:table border=1 cellpadding=3 cellspacing=0:)
(:cellnr align=center colspan=2 bgcolor=#eeeeee:) '''Specifications'''
(:cellnr align=right:) Description:
(:cell:) Strings of 8 in serial
(:cellnr align=right:) Geophone type:
(:cell:) SM-4/U-B, 14 Hz, 375 ohm
(:cellnr align=right:) Damping resistance:
(:cell:) 453 (+/- 1%) ohm
(:cellnr align=right:) String resistance:
(:cell:) 1641 ohm
(:cellnr align=right:) Series resistance:
(:cell:) 1436 ohm
(:cellnr align=right:) String sensitivity:
(:cell:) 126 V/(m/s)
(:cellnr align=right:) String damping:
(:cell:) 0.70
(:cellnr align=right:) Connector:
(:cell:) QXA 4/12 M
(:cellnr align=right:) Cable:
(:cell:) Type U2B8, OD = 8 mm, white PU jacket
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!!Geophone Suspension Unit
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The suspension unit is shown below:
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Attach:geophone-suspension-unit.png
''Geophone suspension unit (last unit in string has cable outlet one end only).''
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Datasheet on Gimbal suspension unit - click image below:
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[[Attach:gimbal-suspension-unit.pdf | Attach:frontpage.png]]
''Click to see datasheet of Gimbal Suspension Unit.''
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!!Geophone Element
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SM-4/B 14 Hz geophone response curves for different damping resistors are shown below.
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Attach:SM-4-B-14Hz-response.png<br />''SM-4/B 14 Hz geophone element response curves for different damping resistors.''
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Complete datasheets of SM-4/B geophone element (two versions) are available by clicking the images below:
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(:table border=0 cellpadding=3 cellspacing=0:)
(:cell:) [[Attach:SM-4-geophone-datasheet.pdf | Attach:SM-4-B-front.png]]
(:cell:) [[Attach:sm-4.pdf | Attach:SM-4-geophone-element-front.png]]
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[[<<]][[<<]]
!GEOPHONES (3-C) USED IN CONJUNCTION WITH VSP
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We consider adding eight 3-component geophones on the surface as a complement to VSP sensors, when this type of survey is performed.
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[[Attach:121013.pdf | Geophone element datasheet]]
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(:table border=1 cellpadding=3 cellspacing=0:)
(:cell colspan=2 align=center bgcolor=#eeeeee:) '''Specifications'''
(:cellnr align=right:) Model:
(:cell:) PE-6, 3-D Geophone
(:cellnr align=right:) Geophone element designation:
(:cell:) SM-4
(:cellnr align=right:) Geophone element natural frequency:
(:cell:) 10 Hz
(:cellnr align=right:) Geophone element resistance (without shunt resistor):
(:cell:) 375 ohm
(:cellnr align=right:) Geophone element sensitivity (without shunt resistor):
(:cell:) 28.8 V/m/s
(:cellnr align=right:) Geophone element markings:
(:cell:) Text moulded in plastic: "SM 4/7 SENSOR"<br />Text engraved in plastic: "H8 10 375 17"
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(:table border=0 cellpadding=3 cellspacing=0:)
(:cell:) Attach:Dscn0714-small.jpg
(:cell:) Attach:Dscn0715-small.jpg
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