Moose River Basin: geology and mineral potential - Geology Ontario

Petrography of Mesozoic and Pleistocene Sands
prised of white, well sorted, well rounded, high sphericity, fine, pure silica sand
with some clay matrix but no organic component. These are very uniform sedi
ments, except that the interval 167 to 173 has only a few granules, all of Pre
cambrian lithologies, while 174 to 176, near the Paleozoic contact, contains a
flood of angular buff limestone pebbles similar to the underlying Devonian
strata. These lowest samples are similar to a basal conglomerate overlying an
unconformity. In this hole sediments overlying the Paleozoic may be divided
into three units at 139 and 153.
DRILLHOLE 75-05
Seven widely-spaced samples, taken from this hole for comparison with
drillhole 75-06, fall into two groups of sands. Samples 26 to 28 are greyish,
poorly sorted, angular, coarse, impure sands with minor calcareous clay, with
out organic matter. Abundant granules contain quartz and Precambrian with
significant limestone. Samples 39, 78, 98,102 consist of very white, well sorted,
angular, low sphericity, very pure, fine silica sand with few granules, minor
noncalcareous clay and no organics. Abundant granules in 39 are 90 percent
quartz with minor limestone, and 100 percent quartz in the other three sam
ples. Definite changes in sand character occur in the interval between samples
28 and 39.
DRILLHOLE 75-06
This hole may be divided at the base of the thick till sheet (Appendix A).
Samples 57, 59, 61 are taken from a light brown-grey, massive, compact, gritty
clayey silt till with few clasts (quartz or limestone), and no organics. Pure,
whitish silt and clay and well sorted, angular, very fine sand with some brown
organics but without pebbles makes up sample 63, whereas sample 67 is simi
lar silty clay containing clay balls and some brown organics.
Samples 75 to 91 are essentially homogenous, containing white, well sort
ed, angular, low sphericity, pure, fine silica sands with abundant clay matrix
and domination of quartz and Precambrian in the granules present. Brown root
hairs and bark-like organics occur in sample 75, and are associated with black
lignitic fragments in samples 76 and 78. Lignite is present in samples 76 to 89.
Sands in samples 93 to 138 differ from overlying sediments. They are
white, moderately sorted, angular, high sphericity, somewhat less pure, me
dium to coarse sands with very little clay matrix and equal proportions of lime
stone, quartz, and Precambrian clasts in the granules. In the last two samples
(134, 138) limestone and Precambrian components dominate the >2 mm frac
tion. In organic content, samples 93 to 97 are barren, samples 99 to 115 very
rich, and below this lignite appears occasionally. Samples 105 and 107 have
abundant clay-size carbon.
The upper three samples (57, 59, 61) represent one till unit whereas sam
ples 75 to 91 appear to be a uniform sand unit. The colour and texture of the
57