Survey Metadata

Tree tissues were collected along transects over kimberlite bodies during a two day period in August, 1992 in the Kirkland Lake area, northeastern Ontario.  At each location tissues of the dominant species were collected: twigs of balsam fir at Diamond Lake kimberlite pipe; twigs and outer bark of black spruce at the C14 pipe; and twigs of both balsam fir and pin cherry at the Buffonta dyke.  At Diamond Lake, balsam fir twigs were collected from 13 sample sites spaced 100 m apart along a 1200 m north to south transect.  At the Buffonta property, pin cherry and balsam fir twigs were collected from 12 sites at 30 m intervals along two transects.  At the C14 pipe, black spruce bark and twig samples were collected along a 400 m transect over the kimberlite from 9 sites spaced at 50 m intervals.  The data are published in Geological Survey of Canada Open File 3005.  A summary of this work can be found in Geological Survey of Canada 3228.

Usually 5 to 7 twigs, each comprising 5 to 7 years of growth were collected, commonly 35 to 40 of twig.  It is important to maintain a consistent ratio of twig bark to twig wood because many of the heavy metals are located in the bark of the twig rather than its woody tissue.  The loose, dead tissue comprising the scaly outer bark of black spruce trees was collected.