Both the ESS and EMS systems are used to survey drill holes in a clean magnetic environment and offer high levels of accuracy. They are simple to operate, robust and light weight enabling them to be easily mobilised to almost any location at short notice. ESS / EMS tools can be run in tandem providing additional data integrity, security and QC. HTotal, Magnetic Field Dip and GTotal are measured as part of QC procedures and check that individual surveys are not compromised.

ESS and EMS are battery powered systems with a built in memory module and can be run on any rig site slick line or braided wire-line unit. The tool can be programmed to suit the application and is armed at surface by the user. Multi-shot Data is recorded at pre-determined time intervals during the survey and on completion can be downloaded immediately for presentation in electronic and printed form.

In addition surveys can be conducted in drop mode where the instrument is dropped or pumped from surface down the drill string. When surveying on completion of drilling this allows the survey to be conducted whilst the drill pipe is tripped out of hole saving rig time and cost. Where the client is conducting diamond coring the ESS / EMS landing sub will bottom out on the core barrel landing plate and the survey can be conducted through the bit on non-magnetic extension rods. For rotary drilling the instrument can be landed out in a section of non-magnetic drill rod a short distance behind the drill bit. For air drilling the instrument is run into the well on a J-Slot release assembly. Once at the landing point the tool is released, the wire-line is pulled out of hole at high speed and the survey conducted whilst the pipe is tripped.

APPLICATIONS:

The most common applications are:

• Accurate delineation of drill path in a magnetically clean environment
• Open hole surveying
• In-rod surveying where a non mag section of drill pipe is used

ADVANTAGES:

• accurate, reliable and quick
• robust and durable in even the harshest environments
• survey shots are independent of the previous shot
• economical, can be run in drop mode
• man packable, easy to mobilise by road or air at short notice
• tools can be run in tandem for added peace of mind