The Yarmouth Drumlin Field, Nova Scotia, Canada

Abstract

ABSTRACT. The Yarmouth drumlinized area is a relatively small field of about 150 drumlins located south and south-east of the town of Yarmouth, Nova Scotia. An analysis of the drumlin shapes indicates that in the majority of cases the stoss end is on the southern extremity of the drumlin. This would suggest that the ice moved in from the south, a concept which is contradictory to pebble lithology and fabric 'analysis of the till in the drumlins and surrounding ground moraine. The drumlin field is anomalous in other respects in that the drumlin density is very low compared with other fields, and granulometric analysis shows that the drumlins are composed of coarse-grained material with only minor amounts of clay.It is suggested that the drumlins were originally formed by south to south-easterly flowing ice but during a later phase of glaciation a local centre of outflow, probably short-lived, developed south of Yarmouth on the continental shelf, and the drumlins were reshaped by ice flowing toward the north prior to the disappearance of this centre. Thus this area of drumlins was presumably not affected by the later area of outflow centred on the interior upland of western Nova Scotia which was hitherto believed to account for the Yarmouth drumlins. On suggere que les drumlins furent a I'origine, formes par de la glace coulant vers le Sud-Est; mais au cours d'une phase ulterieure'de la glaciation, un centre local d'ecoulement, probablement de courte duree, se developpa au Sud de Yarmouth sur la calotte continentale et les drumlins furent refa<;onnes par de la glace s'ecoulant vers le Nord, avant la disparition de ce centre. Par consequent, on presume que cette zone de drumlins ne fut pas affectee par I'ecoulement qui fut centre plus tard sur le plateau interieur de la Nouvelle Ecosse occidentale et que I'on croyait jusqu'ici Clre en cause dans la formation des drumlins de Yarmouth.