896 Transactions. — Geology. 



colour, and sometimes with brown coal or lif^nite. Its greatest 

 elevation above the sea is at Hog's Back (3,300 feet), and Flock 

 Hill (3,200 feet) ; at Prebble Hill its highest point is under 

 3,000 feet. 



Beginning at the southern part of the basin, in Coleridge 

 Creek, we find a small exposure of green sandstone, followed by 

 grey marl, the thickness of which I could not estimate, but it 

 must be more than 50 feet. These are succeeded by 200 or 300 

 feet of limestone, there being no appearance of the intermediate 

 sandstone or grit. The dip is to N.E., at an angle of 50° in the 

 lower part of the marl, gradually flattening to 28° in the lime- 

 stone. Descendmg the creek, we lose the Waipara rocks for 

 some distance, and then once more come across the marls 

 underlain by green sandstone on the eastern side of the basin. 

 The limestone is absent here, and the marls and sandstones are 

 not well developed and rather obscure. 



White-water Creek exhibits the following section (PL XXV., 

 Section III.) :— 



9. Limestone. A few feet only, on the left bank of the 

 creek. 



8. Green calcareous sandstone, with fossils. 40 feet (?). 



7. Pale grey or white marl ; perhaps 300 or 400 feet 

 thick. 



6. Grey shale. 150 feet. 



5. Dark greensands. 



4. Dark soft sandstone with plant remains and efflores- 

 cences of sulphur. 40 or 50 feet thick. 



3. Impure lignite. 3 feet. 



2. Carbonaceous shales and sandstone. 



1. Grey sandstone. 



The dip of beds Nos. 5 to 9 is N.W., flattening from 55° in 

 No. 5 to 40° in the upper beds. The beds Nos. 1 to 4 dip to the 

 N. at angles from 70° to 55°, and there may be an unconformity 

 above them. From this point northward the upper part of the 

 Waipara System is covered by the gravel terrace along which 

 the West Coast Road runs, and it does not reappear until the 

 first limestone gorge of the Porter River, near Prebble Hill, is 

 reached. The green sandstones, however, which underlie the marl, 

 form the banks of the Porter between Table Hill and Prebble 

 Hill, the river running more or less on the strike; just above 

 the first gorge these sandstones, dipping 18° N.W., end abruptly 

 in a fault, which has a downthrow to the north (PI. XXV., 

 Section IV.). This appears to be a reversed fault, the older 

 beds overlying the younger ones, but, as a gully obscures the 

 exact line of junction, I do not feel confident that appearances 

 can be trusted. 



