Geophysics

Nexans, with its Filotex® products, has developed a wide range of cables for seismic exploration in both land and shallow water operations. These products typically suit the oil, gas, and mining industries.

Nexans geophysical cables can be used in very harsh and hostile conditions. They are designed to meet stringent mechanical requirements: resistance to cut-through, heavy wear and tear, resistance to tension and torsion. The cables also have high resistance to moisture, chemicals, solvents and to temperature fluctuation.

Accurate data recording greatly depends on the high quality of the cables used. We ensure the high quality of our geophysical cables using only high grade materials in their manufacturing process. The cable construction/design can often be adapted to meet customer’s specific needs.

Test results on the Filotex® geophysical cables have proved their excellent reliability in seismic exploration for many types of data measurement and most types of electrical requirements.

Our cables are available in many different styles :

• Land cables for high frequency transmission,
• Waterproof cables,
• Geophone leader cables,
• Lightweight constructions….
  

  Mechanical requirements

  Regardless of the cabling system (electrical or optical), our geophysical cables are ideally suited for applications which perform under very harsh ambient conditions:

• Resistance to wear and cut through: polyurethane external jacket,
• Resistance to corrosion: stainless braid is an option,
• High tensile strength: from 50 daN to 3500 daN, with mechanical strength enhancement: central strength member (aramid or special), braid (aramid, or stainless steel),
• Water-resistant cables from 0.5 to 5 bar available,
• Manual or mechanical spooling or de-spooling: mechanical support by braid or central strength member,
• Low ambient temperature cables: whilst maintaining good flexibility and mechanical resistance.
  

  Physical requirements

  Cables meet the expected requirements in appearance and dimensional integrity:

• Cylindrical cross section and ease of moulding,
• Diameters compatible with the most popular connectors,
• Low bulk volume and low weight: permit the cables to be transported by air and ease of handling,
• Matt or gloss appearance.
  

  Electrical and transmission requirements

  Our cables are available in many different styles :

• One or several high frequency transmission pairs or quads (typically 10 MHz),
• One or several geophone pairs,
• Supply conductors,
• One or several optical elements in option.
• Cables meet the usual electrical requirements of the market:
• Attenuation at 10 MHz: typically <= 7 dB/100 m
• Characteristic impedance: typically 145 ohms

  However, we can meet many other specifications depending on the cabling system. Optical elements can be proposed when the cabling system requires a higher flow rate information, longer lengths (typically >1000 m) or low attenuation, which may not be achievable with copper technologies.
  
  Photo: Geo-X