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occur in the small creek immediately below the limestone gorge of Coleridge 

 Creek, at a height of 400 ft. above its floor (fig. 6). They occur again higher 

 up the valley-side in the next tributary on the north side of Coleridge Creek ; 

 a massive detached block occurs in the upper part of Whitewater Creek, 

 and isolated fragments occur on the slopes of Leith Hill, on the western 

 side of the basin, between the Whitewater and the Thomas Rivers. I 

 have been informed that similar blocks occur in the bush immediately 

 south of the Thomas River, and in the Thomas River itself, though I could 

 not locate them. The occurrences near Coleridge Creek are especiallv 



N.W 



Fig. 6. — Section across Coleridge Creek, just below limestone 

 gorge. Distance, £ mile. Direction, N.W.-S.E. 

 1, greywacke ; 2a, sands, greensands ; 2b, marls, 

 &c. : 3, tuff beds ; 4, limestone ; 5, sands, sandy 

 clays, shales, and conglomerates — Pareora beds. 



interesting as they are pinched in between the greywacke and the higher 

 sandy beds of the Tertiary series, and the greywacke has apparently been 

 forced over them along a fault-line. The blocks in Whitewater Creek 

 consist of two beds of limestone, the upper 50 ft. thick ; and underlying 

 this white calcareous sands 40 ft. ; greensands 10 ft.; and white sands oi: 

 uncertain thickness. The lower limestone then follows, 40 ft. thick or 

 more (fig. 4). The beds strike N. 60° E., and dip N. 30° W. at an angle 

 of 35°. There is no appearance of overlying beds. The limestones are 

 no doubt a part of the ordinary limestone series, and have been separated 

 from the beds lower down the creek bv a fault with a north-and-south 

 direction. 



Only the occurrences in the northern portions of the basin are now 



left to be considered, and these present most interesting structural features. 



At the lower limestone gorge of the Broken River the following beds occur, 



all with a N.N.W.-S.S.E. strike and a W.S.W. dip of approximately 20° :— 



Upper limestone, 150 ft. thick, of the ordinary type but carrying 



fragments of volcanic tufa throughout, and at times segregated 



into well-defined layers. 

 Calcareous tuff, 40 ft. to 50 ft. thick, well bedded, and containing a 



high proportion of calcareous material. 

 Lower limestone, about 200 ft. thick, flaky, and well jointed into 



quadrangular blocks. Both of these limestones are coralline in 



origin. 

 In the neighbourhood of the gorge on the north side of the river there 

 are several small faults with a north-and-south direction and a downthrow 

 to the east. When followed round the eastern face of Flock Hill the strike 

 gradually changes, and the dip becomes southerly at the northern end of 

 the ridge, and farther on, when Murderer's Creek is reached, it is to the 



