Moose River Basin: geology and mineral potential - Geology Ontario

Mesozoic Stratigraphy
naibi River in Burstall, McBrien, and Habel Townships (Photos 2.3 and 2.4).
Thickness of the formation varies greatly. In the intensively drilled Ona
kawana area the maximum known thickness is 51 m. However, the Hambly
No. l hole contained a 121.4 m section (Figure 2.9) and in drillhole 75-06 (Fig
ure 2.8) the unit was about 86 m in thickness. Only 8.4 m of the formation was
present in drillhole 75-02 (Figure 2.3) which is believed to be close to the north
ern erosional edge of the unit.
Lithology
A comprehensive account of all lithologies comprising the Mattagami For
mation in its outcrop areas and various subsurface locations was provided by
Price (1978). Therefore, descriptions in this paper are confined mainly to the
new data obtained from the winter 1975 and fall 1977 drillholes. Many detailed
descriptions of individual sand and clay samples from holes 75-01 to
75-06 are contained in the following papers by Hamblin and Vos. Briefly, the
Mattagami Formation consists of an extremely variable sequence of nonlithified
varicoloured clays and silts, white quartz sands, and occasional seams of
lignite. Two sediment associations appear to be present, one typified by dark
grey or black clay and silt commonly associated with abundant detrital or in
situ carbonaceous material, and the other characterized by thick sections of in
terbedded sand, oxidized reddish to light brown clays, and white kaolinitic
clays. In the following lithological descriptions these sediment associations are
referred to as Type A and Type B respectively.
DRILLHOLE 75-01
This drillhole (Figure 2.5) contained an incomplete 33 m section of the Mat
tagami Formation beginning at a depth of 12.8 m. Sediments were of the Type
B association, consisting of white, fine to coarse grained, pure quartz sands in
terbedded with thin horizons of white, red, yellow and light brown kaolinitic
clay. The upper boundary of the Mesozoic sediments was relatively sharp; basal
Pleistocene deposits consisted of a coarse gravel bed overlain by sandy clay till.
The Mattagami Formation section of this drillhole corresponds closely to the
upper 63 m of the Mesozoic section in the Hambly No. l hole, drilled about 11.5
km to the south. The 66 to 129 m interval of the latter drillhole was logged as
white, medium to coarse grained, angular, fluviatile quartz sand with 4 feet to
10 feet clay layers (Aquitaine Sogepet et al. 1973).
DRILLHOLE 75-02
Sediments that are possibly referable to the Type B association of the Mat
tagami Formation occurred between 99.1 and 107.5 m in this drillhole (Figure
39