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average thickneM is 30 cm.
8'
The sandstOBe beds generally appear to be laterally
cominuous within the scale of the outcrops. In places they are slump folded and in at
least one case a slumped horizon is associated with an occurrence of the Dani~l's
Harbour Member (see 3.2.2 below).
Facies AT4 a) sandstone beds art commonly
amalgamated (i.e. they display a clear erosional surface within the bed (Walker. 1961l)).
Each amalgamated bed shows evidence of up to three depositional events. LOJu casts
and pseudonlldules are commonly present at the bases of the beds.
Flute CaslS arc
infrequently observed, a~ much of the exposure is almost !lat lying, but they are common
where the bases of !>cds are exposed. The Ilute casts are typically fairly small (3 cm
muimum width), markedly pointed and elongate. These features arc typical of those
found on the bases of beds which begin with the Bouma (1962) division bore (Pen and
Walker. 1971). Internall) the sandstones show partial Bouma sequences. of which T..
or Til< and T~ are the most common. Cross-lamination, ripple drift cross-lamination and
~onvolute lamination are the most common sedimentary structures. The tops of the beds
are commonly rippled with wavelengths of 15 to 50 cm and amplitudes of 2 to 3 em.
Facies AT4. subfacies b) (plate 3.4) is best exposed in the Betlburns and Table
Cove sections (appendix 1, location map 3), AI these localities the sandstone Deds are
thicker and grain size is generally coarser. The beds show marked lateral thickness
variations over distances of the order of ten metres, and commonly amalgamate along
st"ike. Mean bed thickness is about 30 cm Wilh a maximum thickness of about I m.
T.. and T_ are the most common Bouma divisions displayed in this facies. Climbing
ripple lamination is common and occurs in sets up to 30 cm thick. The climbing ripples