Fast and accurate logging of oriented drill cores
Published 2011-11-15 23:11:46
Petro Team Engineering AB has developed an instrument for accurate measurements of the two angles on oriented drill cores defined by the reference line and the core axis, DCSO – Drill Core Structure Orientator. The work resulted in an instrument that with the help of two laser beams simultaneously measures the angles and transfer them into the software and convert them into true strike and dip.
Oriented drill cores are a powerful tool to estimate the features of the rock masses in 3D. DCSO facilitate rock mechanical stability analysis and design in the planning of underground excavations and slopes. It is also a powerful tool for structural geological analysis.
All measured data is stored in a computer software that comes with the instrument where the measured alpha and beta angles automatically are calculated to true strike and dip. The only data that needs to be manually inserted before the calculation is the orientation of the drill hole, azimuth and dip. In the software it can also be logged information about the rock type, joint roughness number, joint alteration number and general notes about the core for rock mass characterization.
In 2010 NGI (Norwegian Geotechnical Institute) used the DCSO for logging of oriented drill cores in the planning of an underground train station in Holmestrand with 35 m span. The results from logging the orientation of the joints and structures in the drill cores harmonized with the other investigations of the rock mass (geological mapping and seismic investigations) so well that they chose not to do the planned bore hole camera investigations of the drill holes (Kveldsvik Vidar, NGI) The DCSO makes the logging of oriented drill cores easier, faster and more accurate than doing it manually.
The DCSO is available to rent. It is packed in a customized suit case with all the equipment needed. The computer software is included in the rental on a USB – memory only to install on a computer. Petro Team Engineering also offers instructors to help getting started with the logging.
