Borehole Geometry Tool Kit (BGKT*)


The Borehole Geometry Tool Kit (Schlumberger Seismos Prakla VSP Tool) was a three-component VSP tool that was used for many years in the petroleum exploration industry. At the time of its deployment in ODP, it was the slimmest available Schlumberger 3-axis VSP tool.

Each of the BGKT’s three components contained eight 10 Hz geophones. The preamplifier was 20 or 40 dB, selected at the surface.

The BGKT was deployed during ODP Leg 176.

Tool Specifications

Temperature rating: 500° F (260° C)
Pressure rating:  23 psi (158.5 MPa)
Diameter:  3.75 in (95 mm)
Length: 10.5 ft (3.2 m)
Weight: 253 lb (115 kg)
Max. borehole diameter 16 in (40 cm)
Signal conditioning:  Eight 10 Hz geophones/axis with preamplifier (20/40 dB, selected at surface)
Other:  Monolithic tool, no stand-offs

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