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of Ihe Mainland formation, wllkh is Ihe closest 10 Ille Sf. Lawrence Promontory.
Paleollow in lhe Appalachian foreland ba(in tends to be away from major promontories
(HiSCOIt cl OIl .. 1986):
3) Changes in lhe route of sediment supply might have been generated by Ihe choking
off of supply systems through the arrival of the lower sedimentary slices of Ihe Humber
Arm Allochthon in tile Victor's Brook area.
The position of lhe Mainland mid-fan wilh abundant coarse sediment clearly
implies lhe e~istence of another sediment input poim in addition to those outlined in the
discussion regarding the American Tickle formalion. II should also be IlOted. however,
that willi mounfing evidence of structural compJc1{ity in Ihe parautochthollOus sequence
(Waldron and Slockmal, 1991) it i~ unclear whether the Mainland formation was closer
10 a sediment input poim or whether :1 is simply a more marginal facies which has been
transported westward relalive 10 the more uial facies of the American Tickle fc:mation.
These tWO possibililies are not mutually exclusive. It is suggested thaI in view of the
facies present. as well as the sanli/mud ratio. that the former was the case.
The structure of the Mainland Formalion is poorly underSlood but if relalive
verlicalstratigraphic relationships are preserved. as is suggested by the limited Olvailable
evidence. Ihen the Mainland formation changes in character as one goes upsection. The
apparenllop or Ihe exposed section (at Low Poin!) has thicker shale packages which are
punctualed with sandstones which show speclaCular convolute laminations. large scale
scouring and cross-beds. and in places. overturned cross-bedding. Very slrong bottom
currents and/or dilute as well as concentrated turbidily currents are indicated by the