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Ann Series. The ubndor Series included rocks of Cambrian age. The loog PoiN
Series was inferred 10 be of Middle Ordovician age but is now known to include both
paraUiochthonous .!Xi allochdJonous siliciclastic rocks of Middle and Late Ordovician
age. The Humber Arm Series was lhougbl (0 be the young\.'S1 unit of all (Middle or
possibly Upper Ordovician) but the lower pan of mis series contained sandslOnes now
interpreted as bcirll of ClilTIbrian age.
The equivaJelJ:ies of borh Richardson's and
~huchert and Dunbar's units with modem paraufochthonous units are shown in table
1.1.
Further advances required an understanding of the stnlCtural configuration of
weSfcm Newfoundland which came aboul as a result of the work of Rodgers and Neale
(1963), who recognised the existeru of the allochthons in !he region. Steyens (1970)
buill on (he wort of Rodgers and Neale (1963), and Wilson (1966) and included the
pat;1Ulochlhonous Ordovician silkiclastics in a leCtonic·suatigraphic framewort which
renecttd a model ofpusive rmrginevolution and destrUCtion. Stevens (1970) dusiftcd
sandstones of western Newfoundland inlo Allal'lic type and PaciftC type nysch. and
suggesrtd that a reveruJ in provcnance from wesI to elSl: was indicau~d by the preserx:e
ofchromile in all nY5Ch ofposI.Arenig age. Panicular aneMian was j)3id to the Humber
Arm Allochthon where the sedimentary rocks were divided info lower quanzo-feldspafhic
nY5Ch. carbonate flysch. and upper quanzo-feldspafhic flysch.
The Blow me Down
Brook Formation (upper quaruo-feldspafhic nysch) was described as an Ordovician unit
containing ophiolite detritus which indicated IIlaI ophiolites wcre exposed to the east.
The work of Stevens (1970) has provided lhe basis for all subsequent