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Creek, and St. Paul's Inlet. An extensive, although structurally complex, exposure of
the unit occurs as a large raft in melangc (Williams et a\., 1985) in the area around
Lobster Cove, north of Rocky Harbour,
The Lower Hcad Fonnation al the Lobster
Cove locality has be1::n studied in detail by Gonzalez-Booorioo (1990).
The base of the 1...Qwer Head Formation is sharp, bul at 5evcrallocalities red and
green shale and limestone conglomerate, similar to lithologies of the UppennoSI Cow
Head Group, are interbedded with sandstone for several tens of metres upseclion from
the lowest sandstone bed.
Sandstone dykes and sills are conunon at the base of the
Lower Head Formation, at many of the localities where it overlies red and green cherts
and shales of the Green Pain! Formation of the Cow Head Group; e.g. at Western Brook
Pond. 1be dominant Iilhology in the Lower Head Formation is thick· 10 very thickbedded
massive sandstone, with abundant fluid escape stn!.ctures (mainly pillars).
A
distinctive lithology consisting of channelised conglomerate containing cobbles of
limestone and chen supponed by a granule sandstone matrix occurs at several localities,
notably Manin Point South, the south side of St. Pauls InJet, Lobster Cove Head, and
Ponland Hill. The lithologies of the conglomerate clasts resemble those in the
immediately underlying Cow Head Group.
Near Ponland Creek, thick-bedded sandstone is interspersed with packages of
poorly exposed green shale and siltstone which are up to 25 m thick. 1be sandstone
contains limestone granule layers up to 20 em thick.
At this localily a folded
olistostromal horizon, several to's of m Ihick, is also present. It contains large boulders,
up to 5 m long diameter, of conglomeratic sandstone in a pebbly mudstone matrix. This