Feasibility Study and Technical Report - Pretivm

9.0 EXPLORATIONInformation in this section has been excerpted from the Olssen and Jones (2012c), whichwas sourced from sections within Ghaffari et al. (2012) and updated.In September 2011, Quantec Geoscience was contracted to undertake a Spartanmagnetotelluric (MT) survey of the Snowfield and Brucejack Properties. The explorationobjectives were to map and detect porphyry mineralization to depth within the Snowfieldand Brucejack Projects, and to establish an understanding of the geological system andfluid pathways to great depth within the Snowfield and Brucejack survey area (Gharibi etal. 2011).Approximately 57 lines were surveyed at a spacing of 500 m.The following definition of MT is taken from Quantec Geoscience’s report (Gharibi et al.2011):The (MT) method is a passive/inductive method which measures the timevariationsin the Earth’s natural electric (E) and magnetic (H) fields to image thesubsurface resistivity below the sounding site. No source or transmitter is used.The E and H fields are measured over a broad range of frequencies from 10 kHzto 1Hz (worldwide lightning activity), and from 1Hz to 0.001Hz (oscillations of theEarth’s ionosphere as it interacts with the solar wind). While the E and H fieldsare random, (solar wind and lightning activity) the ratio of the fields depends onthe subsurface resistivity structure.The 16 MT stations scattered over the southern part of the Brucejack area provided apreliminary understanding of the resistivity contrasts. There are clear contrasts betweenrock types and a significant interpreted northerly structure that appears to correlate withindicated mineralized zones from Bridge Zone to West Zone. A second interpreted eastnortheaststructure that may off-set the northerly structure is also apparent. The 16stations sparsely cover more than 2 km 2 with significant topography, and showdifferences in resistivity responses between individual stations. While the MT data maysuggest geologic features, it should be used with caution.Three-dimensional figures from the Quantec Geoscience report (Gharibi et al. 2011) arepresented in Figure 9.1 and Figure 9.2.Pretium Resources Inc. 9-1 1291990200-REP-R0012-02Feasibility Study and Technical Report on the BrucejackProject, Stewart, BC