The C14 pipe intruded Archean felsic volcanic and Paleozoic carbonate rocks approximately 156 Ma ago and consists of tuffaceous kimberlite breccia and hypabyssal and tuffaceous kimberlite. The subcropping surface is approximately 200 m by 150 m and is covered by a thick sequence of glacial sediments consisting of 7 to 10 m of grey silty sand till at the base overlain by 25 m of glaciolacustrine clay and silt capped by 2 m of eolian sand. The uppermost part of the till is interbedded with sand layers and was likely deposited as subaqueous debris flows. Overburden is thickest directly over the pipe where the kimberlite has been eroded 20 m below the surrounding bedrock. The relative abundance of indicator minerals in the C14 kimberlite is: pyrope > Cr-diopside > Mg-ilmenite > chromite. Indicator minerals from the C14 pipe can be traced in till a minimum distance of 2 km southwest of the pipe. Till overlying and southwest of the pipe is geochemically anomalous for Cr, Ba, Sr, Ta, Ti and K. Bark and twigs from black spruce trees overlying the C14 pipe are enriched in Sr, Rb, Cr and Ba (McClenaghan and Dunn, 1995; GSC Open File 3005).