2eo 



NOTE OX A (:la<;ially-striateu pavement. 



north-east corner of portion 13 this road is crossed by a creek, a tributary of 

 Webber's Creek, and in this creek, about 100 yards east of the road, a very 

 good section of varve rock is seen, the varves showing a dip of 18° in direc- 

 tion N. 35° W. These rocks are underlain by a dark, fairly massive mudstone 

 possessing a sub-conehoidal fracture and containing indeterminate plant re- 

 mains, and the outcrop is continued up a small tributai'y gully or creek coming in 

 from the south and running approximately parallel to the road and about 200 

 yards to the east of it. Proceeding up this creek about 250 yards one comes 

 upon the pavement, of which there are two exposures in the bed of the creek, 

 separated from one another by a distance of about 2 chains. 



As is frequently the case in the Carboniferous areas, the creek has eroded 

 the junction between the dipping varves and the underlying harder rocks, and it 

 is in this way that the pavement, which has quite probably been obscured by 

 alluvium until comparatively recently, has been exposed. {See Text-figure). 



Oacife 



Fluvio-qlocial Conqiomernte 



Block diagram, illustrating the physiographical and strati- 

 graphical position of the striated pavement 



The total area of the pavement observable is small, probably not above six 

 .siiuare feet at each exposure, but if the overlying varve rock and soil were re- 

 moved a much greater glaciated surface would doubtless be brought to light. 

 The rock has been smoothed, grooved or fluted, and striated, and small indenta- 

 tions have been produced by the "scooping-out" action of the ice. In addition, 

 a little ledge of the rock composing the pavement, which evidently rose about 

 a couple of inches above the general level, has also been glaciated, and now 

 shows sub-horizontal grooving along its vertical face. 



There can bo no reasonable doubt that this striated pavement represents 

 the action of ice. The possibilities of differential erosion along flow lines in 

 the igneous rock of the pavement, and of slickensiding have been considered 

 and rejected, and, besides, the marking's are similar to those observed at Bacchus 

 Marsh (Vic.)' Inman Valley and Hallet's Cove (S.A.) and elsewhere, but the 

 grooves are less deeply incised owing doubtless to the ice-sheet which produced 

 them being thinner than that which glaciated the above three areas so heavily. 



The direction of the striae on the glaciated surface is N.13°W — S.13°E. 

 The sense of the movement of the ice has been determined by the examination of 

 a depression, scooped out on the original floor and subseciucntly filled with varve 

 material, flic profile of which indicates that the ice was moving in a northerly 



