partly after the folding and
metamorphism of the strata. The older acid and basic materials appear as
sheets injected along the lines of bedding of the sediments and are
traceable for considerable distances. They are foliated in places, the
planes of schistosity being more or less parallel with the planes of
bedding in the schists. The older acid rocks are represented by the sills
of granite and augen-gneiss occurring west of Portsoy, south of Fordyce and
near Keith, while the older basic rocks are illustrated by the belt of
gabbro, epidiorite and hornblende-schist which stretches southwards from
the coast at Portsoy, by Rothiemay to Huntly in Aberdeenshire. Veins and
bosses of serpentine are associated with these basic intrusions at Portsoy
and near Grange, one of the veins being traceable at intervals from the
shore southwards in the direction of Knock Hill. The later intrusions are
represented by the Ben Rinnes mass of granite and its basic modification,
the Netherly diorite, east of Rothes. Various mineral localities occur
throughout the county, of which some of the most important occur on the
shore at Portsoy, as for example the gabbro masses in Portsoy Bay with
enstatite, hypersthene and labradorite, the graphic granite with
microcline, muscovite and tourmaline at East Head, the chiastolite-schist
west of the marble quarry, the mottled serpentine with strings of
chrysotile. Resting unconformably on these metamorphic rocks, Old Red
sandstone strata are met with in a few places. Thus, they cross the Spey
and appear in the Tynet Burn east of Fochabers, and extend eastwards to
Buckie. Outliers of these beds appear on the shore near Cullen and south of
Fordyce, while the largest area extends from Gamrie east by Pennan on the
north coast of Aberdeenshire to Aberdeen. The strata consist mainly of
conglomerates and red sandstones, which, at Gamrie and at Tynet, are
associated with a band of limestone nodules embedded in a clayey matrix,
containing fish remains. The more abundant species occurring at Gamrie, as
determined by Dr R. H. Traquair, are _Diplacanthus striatus_,
_Rhadinacanthus_, _Cheiracanthus Murchisoni_, _Pterichthys Milleri_,
_Coccosteus decipiens_. In view of the fossil evidence these beds have been
referred to the middle or Orcadian division of this formation. In the
interior near Tomintoul, another large deposit, composed of conglomerate
and sandstone, occurs, which may be of the same age, though no fossils
|