Improving Borehole Survey Accuracy in Mining Exploration The importance of using the correct gyro survey tools and quality controls for borehole trajectory accuracy in mining
Mining companies invest millions of dollars in exploration campaigns. The main objective of their investment is to obtain core samples and from these core samples they will obtain all the geological and hydrogeological information they need to make an evaluation of the reserve.
These core samples must be clearly positioned geospatially (x, y, z) otherwise they will not have the necessary validity to support any discovery, since they determine the depth and size of the ore body.
Most of the Geological programs are focused on the core orientation however that is only 50% of the task. Stockholm Precision Tools AB Sweden assists our worldwide client’s geological departments with training courses to teach that the other 50% of the challenge is related to gathering accurate borehole survey information. Our training emphasizes that the use of correct technology such as the GyroMaster™ and Gyro RigAligner™ is extremely important.
The best technology is not the one that has the best marketing but the one that complies with standard quality control procedures not only in theory but also in real data comparisons. It’s the task of the mining companies to verify each technology and compare it with real borehole data making in-run and out-run comparisons, verifying that the north-seeking gyro matches the land surveyor. But this is usually not a reliable indication of the accurate result. SPT tools, thanks to the Navibore™ Technology, uses a down-hole autopilot which is capable of finding and correcting itself along a survey path, eliminating all possibility of drift.
The GyroMaster™ has been accepted as an industry standard and this reputation has been gained due to the excellent results that customers are getting from using it. GyroMaster™ is the only north-seeking gyro capable of working in continuous mode from vertical to horizontal. The big advantage is that each data point is measured at each centimeter providing multiple XYZ values which make the ellipse of uncertainty very tight. The accuracy is less than 0,1% of the total measured depth compared to 1% with other competitor technologies.
Stockholm Precision Tools AB approach is totally different to what our competitors are promoting because our highly focused in-country support service includes providing the customer with a calibration service that ensures the integrity and reliability of the tool provided in each country.
In addition our remote control & onsite monitoring service of tool parameters from anywhere in the world ensures SPT can address any issues instantly saving time and money by avoiding having to ship tools out of the country or having people travel to the worksite for repairs. This remote backup service is especially important in difficult times when transportation can be a limitation for many mining companies.
The accurate orientation of the drilling rig is a key factor to avoid the borehole deviation.
For the development of mining drilling campaigns, specialized drilling companies are hired. They have their own protocols and procedures for conducting drilling activities but when it comes to the bore hole survey it is difficult to control the parameters if you don’t have reliable survey technology.
QA/QC (Quality Assurance / Quality Control)
This is an area where SPT has dedicated resources and developed a borehole survey gyro technology that has automated internal QA/QC procedures ensuring that every bore hole meets or exceeds the QC requirements. Each survey is evaluated automatically by our in-house designed intelligent software application which includes an integrated error model capable of preventing any problems with erroneous data and thus securing the customer investment. In addition our portable automatic calibration stand is always available in each county.
As part of the drilling program, the mining company provides an action plan that includes the starting coordinates of each drilling point. The drilling company must then assign its machine to ensure that it is starting at the exact place that has been assigned according to the plan (Inclination or Dip Angle, Azimuth, and Coordinates). This control is as equally important as the well trajectory measurement.
Reduce integration risk
If the drilling rig does not start with the initial data provided by the mining company, there is a risk of economic loss (loss due to drilling at a wrong point, or additional cost for repeating or reinstalling the machine with the actual data).
If the drilling rig starts correctly with accurate information and in the final measurement there is still a difference in angle and / or azimuth, it is an operational or terrain problem.
Contact our experts to know more
Please get in touch with us if you need assistance or further information about SPT Tools.