TORONTO (miningweekly.com) – Nonprofit organisation Geoscience BC has employed a novel geochemical exploration technique sampling coniferous tree tops to investigate the geology and mineral potential of a 24 000 km2 swath of Central British Columbia.
As part of its C$4-million multidisciplinary project, Targeting Resources through Exploration and Knowledge (TREK), the organisation had, over the past three years, aimed to garner a better understanding of an area that extended south from Vanderhoof and Fraser Lake and west from Quesnel.
“It’s well established that coniferous trees such as spruce can pick up metals and other elements from the soil and concentrate them in the bark, twigs and needles. Through this programme, we hope to provide new information that will encourage people to take a fresh look at the area’s mineral potential,” stated Geoscience BC VP for minerals and mining Bruce Madu.
Geoscience BC was looking at whether concentrations of trace amounts of metals found in trees could lead prospectors to the next big mineral discovery.
According to the organisation, Coniferous trees, such as spruce, were useful as a biogeochemical sample medium, since they could tolerate and maintain significant concentrations of trace elements. Extracted from underlying materials such as soil, overburden, groundwater and bedrock, elements were absorbed and transported throughout the tree, including twigs and needles where elements could be locally concentrated.
Analytical data derived from treetop samples that had been systematically collected and prepared could be used to identify point-source anomalies and geochemical trends, advised Geoscience BC.
The organisation on Monday stated that it was releasing the data of an innovative tree-top sampling programme led by Noble Exploration Services.
As part of the TREK project, a total of 421 side-branch samples, comprising 1 kg of twigs and needles, were systematically collected near the tops of healthy, 80- to 100-year-old spruce trees over a six-day period in June 2015. Samples were collected using a helicopter flying over a 1 000 km2 area in the Chilcotin Plateau of central British Columbia.
Geoscience BC said it would discuss the results of the tree-top sampling programme at the twenty-ninth Annual Kamloops Exploration Group (KEG) conference this week.
The organisation advised that helicopter-supported tree-top sampling could be an effective way of quickly acquiring samples over large inaccessible areas, and was particularly well suited to the Chilcotin Plateau. The area was relatively flat, had a variety of overburden materials, few lakes and limited road access that restricts traditional sampling options. This area was also located about 15 km south of the Blackwater Gold project, the site of a proposed openpit gold and silver mine with proven and probable reserves of 8.2-million ounces of gold and 60.8-million ounces of silver.
“The regional scale of this tree-top sampling programme is a new venture for Geoscience BC. It’s a pilot programme designed to evaluate the effectiveness of this technique over a much larger area than previous projects,” added Geoscience BC president and CEO Robin Archdekin.