Thomson. — Gtnlogy of Middle Clarence and U re Valleys. 295 



Table II. — Summary of Geological History of the Area. 



Stage of early Notocene sea-advance, 

 w'ith local vulcanism. 



Continued erosion of adjacent mountains to 

 pencplanation. with deposition of Clarentian 

 beds, including local lava-flows ; invasion of 

 pre-Notocene rocks by dykes and sills. 



Local epeirogenic uplift. 



Local unconformity between Clarentian and 

 Amuri limestone. 



Stage of maximum Notocene sea- 

 advance. 



Submergence of land ; deposition of Amuri 

 limestone and Weka Pass stone, divided by 

 a period of non-deposition. 



Slight regional or differential upHft. 



Initiation of antecedent or anteconsec|uent 

 drainage. 



Kaikoura orogenic movements. 



Elevation of Kaikoura and Looker-on Ranges, 

 with folding and faulting of the Notocene 

 beds ; development of consequent drainage ; 

 heavy erosion of mountains with develop- 

 ment of insequent drainage ; mature erosion 

 of valley lowland with slight development of 

 subsequent drainage. 



Slight regional uplift. 



Rejuvenation. 



The area has experienced two epochs of major diastrophism — i.e., two 

 epochs of severe earth-movements of an intensity sufficient to raise moun- 

 tain-chains—which have left their effects clearly marked in the structure 

 of the rocks, while there is evidence for a still earlier epoch in a neighbouring 



