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conglomera!e cont2ins cluls of black siliceous shale, grey lIJiIlite. dark ~n. reddish
or onnge chen, light Krten chen, laminated fUle grained limescone. dolomitic siltstone.
pyrite nodules, and mafIC volcaJUcs. ClastS are sumngulu to rourxled. They may be
murix stIpponed. in which asc the matrix consists ofsanc1stone or silty argillite. or lhey
may be clast supported. The muimum long diameter of lhc c1UlS is 20 em with a mean
long diameter of about] em. Some clasts arc platy and art aligned parallel 10 bedding.
Also included in the Howe Harbour member are vcry coarse sandstone - granule
conglomerate layers 1 10 2 em thick composed predominanlly of black and green shale
detrituS. Towards the contact with the slrucrurally overlying Northwest Ann Fonnation,
these horizons become thicker. reaching a maximum d1ickntss of 40 em. The thin layers
are oomu.Uy graded, whereas the lhiclr:er layers may be trough cross laminated. All of
lhc above lithologies are displayed at the type section for the Howe Harbour member
(appendix I. IOCJlion map 4), which. however, is deformed and possibly imbricated close
10 lhe concact with the Nonhwesc Ann Fomulion.
Bolh of the conalomet1.tt: beds exposed in the nonbeasl area of Howe Harbour
have a maximum thickness of abool 40 em, but vary laler21ly in thicltness as the bases
of the beds may have as mllth as 20 em erosional relief. The thickness and number of
oonglomer.ates in the Howe Harbour member is variable and Williams and Smylh (1983)
ltave r«orded individual thicknesses of up 10 10 m for the conglomer.ate beds. 'The
Howe Harbour member is interbedded with silly argillite of the American Tickle
formation and is reslricted 10 localities where the American Tickle fonnation is
slnlCturally overlain by the Nonhwest Arm. Formarion of the Hare Bay Allochthon. The