58 



Jutson and Chapman : 



•but that the hardened drift of the stream bed remains, capping the 

 hill. 



Since Mr. Hart wrote, some very small excavations on the top of 

 the hill have been made. 



General JJescription of the Outcrops and Sections. 



The country surrounding Sugar Loaf Hill consists of Silurian 

 sediments (mainly shales with thin bands of sandstone), with a strike 

 some degrees to the east of north. We believe the main part of the 

 hill to be of similar lithological character, and the rocks to possess 

 a similar strike, although the latter point is not directly ascertain- 

 able. 



On the top of the hill a band of rock (which we regard as a felsitic 

 dyke intrusive into the Silurian) runs approximately north-north- 

 west for about 300 yards. A l)raiah is thrown off from about the 

 centre, and runs northerly for about 100 yards on the east of the 

 main portion of the dyke. The outcrops are faint for about 50 

 yards north of the bifurcation. Between the two branches of the 

 dyke tliere is exposed a moderately coarse-grained sandstone, with thin 

 quartz veins. The width of the dyke varies from about 6 to 30 feet. 



Associated with the dyke is a very coarse-grained breccia, which 

 we consider to l)e a fault — or friction-breccia formed subsequently to- 

 the dyke. 



At a shallow excavation about 18 inclies deep, and aljout •") feet 

 long, towards the southern end of the main outcroj) of the dyke, a 

 small but interesting section is disclosed, which is slunvn by the 

 following diagrammatic figu)-e : — 



\\\ S^/i/nar? -j"j- fe/5//-e PyAe fX "(F^hihc 3recc^c^). 



of fehf^fc ro<A, . 





