/  Geoscan-R - while drilling formation resistivity wave measurement (logging) device

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GEOSCAN-R - while drilling formation resistivity wave measurement (logging) device

GEOSCAN-R - dual-zone wave logging tool for while drilling formation resistivity measuring (LWD). The device is designed for geosteering to separate oil and water-bearing environments for prompt correction of well trajectory during drilling. GEOSCAN-R can be equipped with a pressure measuring sensor while drilling (PWD) and used to track changes in reservoir pressure.

Key features:

  • Operation principle — phase shift measurement during the passage of electromagnetic waves in the formation,
  • Standard operating frequency — 2 MHz,
  • Possibility of usage on all types of muds with density of not less than 900 kg/m3, including salt and oil-saturated,
  • Fully compatible with all range of GKSTM positive mud pulse MWD systems,
  • The device is powered by a downhole generator, performance does not depend on battery resources,
  • Measurement data coding is carried by GKS inclination module; the data transfer to the surface is made as a pert of the drilling frame,
  • Measurements can be recorded in the device memory with a frequency of 8-200 s (depending on the rate of penetration),
  • the device is provided with a software package that includes downhole conditions indications correction module (mud, the ratio between the borehole ant the tool diameters), interpretation and geo-steering modules.

Permneftemashremont JSC выпускает приборы GEOSCAN-R двух типоразмеров: 178 и 108 мм.

General options:

Parameter / tool size



Body outer diameter

108 mm

178 mm

Body length

2000 mm

2000 mm

Operating temperature range



Maximum allowable pressure

90 MPa

90 MPa

Maximum intensity of the well curvature

drilling without rotation

8°/10 m

6°/10 m

drilling with rotation

4°/10 m

3°/10 m

Mud flow rate range

110…222 gpm

380…586 gpm


Resistivity measurements:




Accuracy at 10 Ohm*m

2 MHz


0,1 – 1000 Ohm*m

± 1%


0,1 – 200 Ohm*m

± 2%


Distance between transmitter and receiver:

Transmitter / receiver

Small-range receiver

Long-range receiver

Small zone transmitter

305 mm

457 mm

Middle zone transmitter

610 mm

762 mm


Recognition area depth, vertical resolution:

Recognition depth

at 0,2 Ohm*m

at 20 Ohm*m

Vertical resolution

Phase — small

457 mm

991 mm

152 mm

Phase — middle

559 mm

1372 mm

152 mm

Amplitude — small

762 mm

2184 mm

152 mm

Amplitude — middle

965 mm

2642 mm

152 mm