Archaean Sedimentation: Analysis of the Minnitaki Basin, Northwestern Ontario, Canada

Four main facies have been identified in the East Bay area of Minnitaki Lake. The first consists of coarse arkose and arkosic conglomerate. Individual beds are commonly graded but lack other sedimentary structures. Plagioclase makes up 30 to 40 percent of the rock, and quartz about 6 percent. The second consists of graded graywackes interbedded with slates. Quartz here reaches about 20 percent, plagioclase only 15 percent, and rock fragments 10 …