To: Jackleg who wrote (4018 ) 2/25/1998 11:37:00 AM From: philip trigiani Respond to of 7966
Conclusion > >In conclusion, there are several reasons for believing Alberta is >geologically favourable for the existence of important diamondiferous >kimberlitic diatremes, including: (1) thick Precambrian continental >crust is present in both north-central and southern Alberta; (2) a >complex regional and local structural setting exists in places in both >the southern and northern parts of the province, which include >numerous long-lived faults and faulted zones that may have facilitated >access of kimberlitic magmas from the deep mantle to the surface; (3) >there are stratigraphically and geochemically anomalous bentonites >which may be derived from local volcanic or kimberlitic extrusive >centers; (4) there are several areas within Alberta which have been >identified by widely spaced sampling to contain anomalous diamond >indicator grains that in some places include micro or macro diamonds >that have not, as yet, been traced to a bedrock source; and most >importantly, (5) there are at least 15 kimberlitic diatremes in north- >central and northwest Alberta, of which 10 are known to be >diamondiferous and several are reported to have micro diamond and >macro diamond counts which are similar to the early phases of >sampling of the diamondiferous kimberlites which exist at the >economically important Lac de Gras region, N.W.T. In short, we >conclude that, at present, ALBERTA IS INADEQUATELY >EXPLORED FOR DIAMONDIFEROUS DEPOSITS.SELECTED REFERENCES > >Dufresne, M.B., Leckie, D.A. and Eccles, D.R., In Press. Study of the > geochemical and stratigraphic setting of the Shaftesbury > Formation in northern Alberta and its potential to host ore > deposits; Geological Survey of Canada Open File Report. > >Dufresne, M.B., Eccles, D.R., McKinstry, B., Schmitt, D.R., Fenton, > M.M., Pawlowicz, J.G.