Geological magazine . reland, and were examined by the writer in thesummer of 1910. They are both lowland districts formed ofCarboniferous rocks, the first lying around the village of Pettigo,north of Lough Erne, and the second around the towns of Donegaland Ballintra. These areas are separated by a ridge of high moorlandformed of metamorphic rocks and indicated by the course of the400 foot contour shown on the map on Plate VIII. Such striae as havebeen recorded in the district are also indicated on this map, and itwill be seen that their direction corresponds very well with that ofthe adjoini
Geological magazine . reland, and were examined by the writer in thesummer of 1910. They are both lowland districts formed ofCarboniferous rocks, the first lying around the village of Pettigo,north of Lough Erne, and the second around the towns of Donegaland Ballintra. These areas are separated by a ridge of high moorlandformed of metamorphic rocks and indicated by the course of the400 foot contour shown on the map on Plate VIII. Such striae as havebeen recorded in the district are also indicated on this map, and itwill be seen that their direction corresponds very well with that ofthe adjoining drumlins. In the district lying south-east of the moorland there are severalrather distinct types of drumlin topography. To the north-east ofPettigo elongated hills occur with axes trending south-west. Someof these are composed entirely of drift, but others appear to be mouldedon solid cores of rock, and in general in this area it is difficult to pickout the solid features from those due entirely to deposition. The. Fig. 1. View looking south-east from Carn Upper, near Pettigo, co. Donegal,across the direction of ice-motion. Gently domed drumlins of shortly ovaloutline. country is deeply grooved and ridged in the direction of the ice-motion,which, there is every reason to believe, was just here more constant inits trend than further south-west. Such undoubted drumlins as occurare elongated and of the form most aptly described as they show a tendency to develop a crested form similarto that of the drumlins of the Ballintra district to be described around Pettigo the predominant form of ground-plan isa short oval, and the tops of the hills are gently domed without anytrace of a central ridge or crest. In Fig. 1 an attempt is made toportray this type of drumlin topography, and the contours on the eastof the map in Fig. 2 also show well the character of a number ofdrumlins of this type. Further west in the neighbourhood ofCarntressy and
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Keywords: ., bookcentury1800, bookdecade1860, booksubjectgeology, bookyear1864
