Sedimentary Rocks. 73 



IX.— Kerrie Conglomerate. 



(a) Field Relations. 



Messrs. Skeats and Summers 33 have drawn attention to the 

 difficulty of understanding the relation of the Kerrie Conglom- 

 erate to neighbouring rocks. For descriptions of the Conglom- 

 erate reference should be made to their memoir or to Mr. Hart's 

 paper. Messrs. Skeats and Summers 34 state that " it is probable 

 that a line marking the western extension of the Conglomerate 

 would indicate the junction between Upper and Lower Ordo- 

 vician rocks in this area," and in another place mention 35 that 

 the Conglomerate " overlies apparently unconformably shales 

 from which no fossils were obtained." They state that the Con- 

 glomerate is in their opinion basal Upper Ordovician. In the 

 absence of fossils any opinion was necessarily tentative. The 

 shales are brown and light blue, and very rubbly. There are 

 occasional narrow dark blue bands. In these respects they are 

 unlike the Lower Ordovician shales with which we are acquainted, 

 but closely resemble Upper Ordovician shales on Jackson's Creek. 

 We had found that at the latter outcrops, graptolites occurred in the 

 dark bands, and carefully splitting a dark band at Conglomer- 

 ate Creek, we obtained several specimens of a Diplograptus re- 

 sembling those found at other Upper Ordovician outcrops. At 

 two localities further west similar graptolites were obtained. 

 These shales cannot be referred to beds below the Upper Ordo- 

 vician. The shales apparently underlie the Conglomerate, which 

 outcrops further up the hills. 



Messrs. Skeats and Summers also refer to Emu Creek, a 

 locality to the north-east of the area discussed in this paper. They 

 state: 36 "On the Emu Creek in Allot. 48a, Parish of Kerrie, 

 another find of graptolites was made; Dr. Hall identified Diplo- 

 graptus foliaceus and DicellograpHis elegans. The beds dipped 

 at a high angle downstream in a south-easterly direction, and 

 again the Kerrie Conglomerate occurs only to the west and north- 

 west of these beds. A short distance upstream from the point 

 where the graptolites occur the conglomerates occur in situ dipping 

 downstream, and conformable with sandstones overlying them. 

 Above this shales come in and further upstream conglomerates 



33. 4, p. 45. 



34. Ibid. p. 14. 



35. 4, p. 41. 

 .36. 4, p. 41. 



