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(Williams and SteveN, 1969: Waring. 1975; Hiscoutlal.. 1984). 1lle lower pari of the
unit has been interpreted as having been deposited by braiojed sueams (Iliscoll ('I al ..
1984) and the upper pan is of shallow marine or:gin. On the islall(i of 'kite Isle. -llll!lC
oonhern lip of the Northern Peninsula. the Bradore Formatioll uncollformably llverlies
mali..: volcanics of the Lighthouse Cove Formation (Williams and St(:\'ens. 1%9). T11CSC
volcanics are conlinoous with mafic dykes which intrude the crystalline basement 300 ate
generally interpreted as having been formed during the rifling process.
Williams and Sl~ns (1969) described the fnmelliork constituentS of the Rradofe
Formation as quanz and feldspar. with local magnetite and minor RlelalTlOtphic rock
fragments. They reported Ihe presence of purplish amygdaloidal basallic nx:k fragments
in places but described these occurrences as being restricted to ceruin horizons. The
author was able to study ronglomeratic and pebbly sandstones from the Bradore
Formation collected by N.P. james and also rollected some pink pebbly sandstone willi
abundallt skolithos burrows from a locality near Hawke·s Bay. No samples were poillt
counted.
1lIe grains are well rounded, and are cemented by quartz overgrowtlis.
Quart!
3.."ld powsium feldspa.rs (boUt microcline and orthocbsc) predom;lIille. The chemislry
of lhe Bradore shows very low levels of trace elemcnu reflecting the dilution effect of
abundant silica in the unit. In fact, the loading 011 sitica is so high Iltal the analyses do
nm plol on the discrimination dialitram of Roser arwl Korsch (1988) tfi, ure 6. I). This
is not surprising. since the diagrams of Roser and Korsch (198[') are essentially designetJ
for turbidites. Otherwise the Bradore clearly displays the si~naf"Jre of having been