Hello Russett
Actually, the craton and points north and south were in fact temperate and tropical in the not very distant past. There are fosils and petrified wood found 200 meters down in Lac de Gras pipes and totally preserved petrified forests up on the arctic islands to testify to that, as do the Mississippi lead/zinc deposits around Pine Point south of Great Slave Lake, the Mackenzie Valley and Beaufort oil deposits, coal seams and the heavily fossilized limestones from Rae/Edzo 100 km west of Yellowknife all the way down through Alberta.
In short, there has been ample opportunity for tropically eroded alluvial deposits to have been laid down, buried, eroded, reburied, eroded, pushed and/or washed thousands of miles south and north and ground to dust.
More recently released glacially scoured diamonds may well have been deposited at the bottom of Great Slave Lake which is over 2 km deep in places but to be realistic, there is no chance in this universe that Fisheries and Oceans and the environmental lobby would allow any major or even minor placer mining in any major drainage system, lake or Arctic Ocean bench. Even the dry benches along the arctic coast raised due to isostatic rebound would more than likely be considered out of bounds.
I cannot recall the name of the junior, but early on in the NWT diamond rush, one promoter was actively pushing the possibility of placer mining the north coast, but that story did not last more than a season or two. Teevee might remember the play's name.
The idea of G11's & 12's being indicative of anything in the diamond industry is news to me. I cannot recall reading any reference to them in any papers or geological posters.
If someone at WSP suggested this to you I would be interested to read a paper on the subject, if your source could direct me to the author, title and date?
I always react to such stories with a healthy dose of "show me" as I have heard far to many promoters and IR salesmen spin some crazy story to push paper or support a price. Whether its time tested geological laws do not apply in Canada, kimberlite that emplaces like plastersine rather than C4, platinum in dessert limestone, oil in granite, cold fusion, or 200,000,000oz gold deposits in Indonesian jungles.
I’m from Philly!!!
Elizabeth:
There have been several quite large alluvial diamonds found in southern Ontario, Michigan and Wisconsin I believe over the past 150 years. If memory serves, at least one was over twenty carats.
They have long been believed to have been deposited by glaciers from some fabulous Ontario pipes buried somewhere, possibly James Bay, but no one, including, Spider, Diagem, DeBeers, Ashton, Kennecott, or KWG has ever found the source.
Coincidentally, Wisconsin has a significant graben which in Angola is the main structure associated with kimberlite pipes and elsewhere associated with PGE deposits, but I do not believe Wisconsin is friendly to the mining industry.
Regards |
