Gold and copper explorer Torrens Mining Limited (ASX: TRN) has commenced a passive seismic survey at its 100% owned Mt Piper gold project in Central Victoria, where it is also undertaking a soil geochemical sampling program. The Mt Piper project is located only 30km from Kirkland Lake’s Fosterville gold mine and only 1km from Mandalay Resources’ Costerfield gold mine.
Passive seismic surveying is a surface geophysical survey method, used to rapidly define geological structures, which may focus gold mineralisation, and the thickness of cover rocks. The survey is non-invasive and involves the measurement of natural or ambient seismic vibrations.
The results will be used to help Torrens to plan drillhole locations and targets.
Survey data is collected using a “tissue box” sized miniaturised seismometer which is placed on the ground at 50m spacings and left in place for 20 minutes, during which time the geologist undertaking this work maps the surrounding geology. The survey data is downloaded at the end of each day’s work and the results processed by consulting geophysicists, Resource Potentials, in Perth, with results expected by early April 2021.
In 2019, a passive seismic survey was completed in Victoria by a University of Melbourne Honours student and was sponsored by Chalice Mining Limited. The survey was completed over Chalice’s Pyramid Hill Gold Project and was designed to characterise the depth to the basement. The results are reported to have successfully defined the bedrock (Castlemaine Group) and several geological structures.
Torrens Managing Director Steve Shedden said:
“The use of passive seismic in gold exploration is a relatively new technique, but we’re excited to employ it at Mt Piper, given the success Chalice Mining had at their Pyramid Hill Gold Project. Torrens has also been involved with its use at its Elizabeth Creek Copper Project in South Australia.
“This non-invasive geophysical technique is expected to greatly improve Torrens’ understanding of the basement structures and materially assist us in refining our drillhole locations for 2021.”
Ongoing soil sampling, passive seismic surveying and geological mapping over gold.
Regional geophysical interpretation and target generation.
Planning of first-pass drill targeting.