Hello LMBF
I probably should have added the following observation to my post your are referencing.
Mag lows especially along faults can be caused by certain geological conditions and are not necessarily kimberlite pipes. These could be geothermally leached rocks (metals removed) or isolated sedimentary blocks surrounded by granites or magnetically higher volcanics.
I would certainly be more optimistic if they were coincident with a pronounced EM response and/or significant bathyometric depressions. Regardless, they were distinctive albeit not extreme lows in an otherwise moderately more magnetic and featureless background, and they did appear to obliterate the mag high from the cross cutting diabase.
Generally, the magnetically noisier area appeared by far to be the central and southern portions of the lake, with multiple relatively intense small circular highs and lows, but as I said, I believe Walter indicated that only one of these proved to be a kimberlite and it was a narrow dyke.
One other observation you should probably keep in mind. WSP's down ice float was I believe of a relatively modest size. While this is not a significant indicator one way or the other, you would think that float of a larger size would be found down ice from a pipe.
Regardless all this is just arm chair conjecture. WSP could put the whole matter to bed quickly enough by taking lake bottom samples immediately over those two lows and over any observable lake bottom depressions. These could be analyzed quickly enough and any resulting elevated combined levels of magnesium, chromium, nickel, rubidium, niobium, clinopyroxene, olivine, uranium, etc, would be suggestive that they ought to consider spending a few dollars drilling these targets. If the lake bottom samples came back with unremarkable levels of these minerals, the expense of drilling probably could be avoided.
Waiting of course keeps the speculative bubble afloat.
Regards |
