... mode. Directional work at the hard rock formation posed an additional challenge. In early 2014, a hybrid high-build-rate rotary system was applied to deepen the kickoff point and avoid the steering work in the hard zone. Air drilling was used to drill vertically across the hard rock. A power rotary...

... Figure 3 Underground drilling setup to collect cuttings with air flush drilling. Figure 4 An example of gas content measurement from air drilled cuttings desorption. Figure 2 Example of lost gas determination plot (Q1). Figure 1 Example of desorbed gas measurement...