Thomson. — Geology of Middle Clarence and U/r Valleys. 



289 



Art. XXXII. — The Geology of the Middle C.arence and Ure Valleys^ 



East Marlborough, New Zealand. 



By J. Allan Thomson, M.A., D.Sc, F.G.S., Director of the Dominion 



Museum. 



[Read before the New Zealand Instilute, at Christchurch, 4th-8th February, 1919 ; received 

 by Editor, 17th March, 1919 : issued separatehj. Kith July, ^1919.] 



Plates XXIV-XXIX. 



Contents. 



Introduction 



General Account of the Geology and 



Physiography 

 Pre-Notocene Rocks 



Intrusive Rocks in the Pre-Noto- 

 cene 

 Notocene Rocks 

 Clarentian Rocks 



Coverham . . 



Isolated Hill Creek, Ure Valley 



Upper Ure Valley 



Middle Ure Valley . . 



Lower Ure Valley 



Mead River. . 



Liraburne Stream 



Dee River . . 



Branch, Dart, and Muzzle Rivers 



Bluii" River . . 



Gentle Annie Stream . . 



Herring (or Sejnnour) River 



Quail Flat . . " 



Nortli Bank, Clarence River, 

 opposite Tvtler Stream 



Red Hill .". 



Clarence River below Bluff River 



Amuri Limestone and Weka Pass 



Stone 



IMead Gorge 



Limburne Gorge 



Dee Gorge . . 



Chalk Range 



Isolated Hill Creek 



Upper Ure Valley 



Middle Ure Valley 



Branch, Dart, and Muzzle Rivers 



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323 



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325 



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Notocene Rocks — continued. 



Amuri Limestone and Weka Pass 



Stone — continued. 

 Bluff River . . 

 Gentle Annie Stream 

 Bluff Hill and Limestone Hill. . 

 Herring River 

 Age and Origin of the Amuri 



Limestone 

 " Grey Marls " 

 Mead Gorge 

 Limliurne Gorge 

 Dee Gorge . . 



Up})er Swale and Ure Rivers . . 

 Dart River . . 

 Muzzle River 

 Bluff River . . 

 Herring River 

 Age and Formation of the " Grey 



Marls" .. 

 Great Marlborough Conglomerate 



and Awatere Beds . . 

 Mead Gorge 

 Dee Gorge . . 



Upper Swale and Ure Rivers . . 

 Dart River . . 

 Muzzle River 

 Bluff River 

 Se3-mour River 

 Deadman's Creek 

 Origin and Age of the Great 



Marlborough Conglomerate . . 

 List of Papers cited 

 Postscript (February, 1919) 



Page 



327 



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340 



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344 



348 

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Introduction. 



The middle reach of the Clarence River occupies a nearly straight valley, 

 some fifty miles long, trending north-east, between the enclosing ranges 

 of the Seaward Kaikoura or Looker-on Moimtains to the south-east and the 

 Kaikoura Mountains to the north-west, which rise to heights of 8,516 ft. 

 and 9,465 ft. respectively. The summits of these ranges are twelve to 

 fourteen miles apart across the valley, so that the area of this part of the 

 valley is some 600 square miles. The north-eastern end of this middle 

 10— Trans. 



