Moose River Basin: geology and mineral potential - Geology Ontario

Moose River Basin
DRILLHOLE 75-06.
In the central part of Mccausland Township, 21 km southeast of drillhole
75-01, a hole was drilled at the winter-road crossing of the Opasatika River.
Mattagami Formation sands and clays (88 m) were intersected from a depth of
52 m to the contact with Devonian shales at about 140 m. Two samples (clay 16
and clay 17) taken near the top of this section proved to be largely quartz silt
with some chlorite, illite, and plagioclase. The absence of kaolinitic clay sug
gests that the material was reworked or deposited after kaolinization had
taken place. The quartz silt is too fine for use as glass sand.
Clay 18 (127.7 -132.6 m) is a brownish grey kaolinitic clay with super-duty
refractory characteristics (P.C.E. 34), a high alumina content (29*-fo A1 2O3 ) and
medium plasticity. Lignite and oolitic siderite occur in the coarse fraction. The
clay may be best suited to upgrade less refractory but more plastic clays.
Clay 19 (132.6 - 135.7) is brownish black kaolinitic clay with an apprecia
ble amount of lignite (estimate: 39fc) and some quartz. With a high refractori
ness (P.C.E. ^4) and higher plasticity than clay 18, clay 19 enhances the use
fulness of the combined intersection of 8 m of clay near the base of drillhole 75-
06.
Clay 20 (135.7 -140 m) is an olive grey chloritic clay occurring within a few
metres of the contact with Devonian shales. Its character reflects much closer
the composition of these shales than of the fireclays of the Mattagami Forma
tion. Kaolinite is absent. A low refractoriness (P.C.E. 7Vz) and low alumina con
tent (IS.9% of A1 2O3 ) restrict the economic potential of this clay.
DRILLHOLE 75-05.
Approximately 4 km north of the Precambrian escarpment, where the win
ter-road crosses the Waboose River in Acres Township, this drillhole was
drilled to a depth of 88 m. Mattagami Formation deposits were intersected from
22.5 m to the bottom of the hole. Geophysical results indicate that at least an
other 60 m of Mesozoic deposits may be expected.
In terms of economic potential, drillhole 75-05 presents the most interest
ing section. Sampled almost in its entirety, eight clay samples and five sands
were collected and analysed. The clay samples represent a total thickness of
27.25 m of kaolinitic clay.
Clay 8 (23.1 - 26.2 m) is a pale yellowish brown kaolinitic clay with minor
mica and feldspar in the coarse fraction. Whether or not this clay is suitable as
ceramic clay for whiteware production depends on firing characteristics (e.g.
burnt color). It has low brightness (23.3*^) and medium plasticity. The alumina
content is 26.1 percent; the refractoriness (P.C.E. 30) is characteristic of high
duty fireclay.
Clay 9 (32.3 - 37.2 m) is a greyish orange kaolinitic clay with some quartz,
illite, and traces of muscovite and limonitic siderite. The refractoriness (P.C.E.
29) corresponds with intermediate-duty fireclay.
Clay 10 (37.2 - 40 m) is a light-brownish-grey sandy kaolinitic clay. The low
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