CONDITIONS OF DEPOSITION ON THE CONTINENTAL 
SHELF AND SLOPE 
Cc. A. COTTON 
Victoria University College, Wellington, New Zealand 
CONTENTS 
INTRODUCTION 
OPINIONS AS TO THE MODE OF FORMATION OF THE CONTINENTAL SHELF 
THE PRESENT-Day SHELF LARGELY CONSTRUCTIONAL 
The Hypothesis That Marine Erosion Is Alone Responsible for the For- 
mation of the Continental Shelf 
The Hypothesis That Subaérial Planation Followed by Submergence 
Explains the Continental Shelf 
The Hypothesis That the Continental Shelf Is Formed as a Result of 
Deposition 
THE STRUCTURE OF THE BUILT SHELF 
With the Shore Line Fixed in Position 
With the Shore Line Advancing 
With the Shore Line Retreating 
With the Shore Line Alternately Retreating and Advancing 
LITHOLOGICAL CHARACTER OF THE BEDS 
STRUCTURE OF A SHELF BUILT DURING POSITIVE MOVEMENT 
STRUCTURE OF A SHELF BUILT DURING NEGATIVE MOVEMENT 
INTRODUCTION 
Undoubtedly deposition of sediment has gone on around the 
margins of the continents in all ages, forming thick accumulations 
which have encroached upon the ocean basins. To what extent 
such marginal accumulations have been later uplifted and thus 
added to the continents may be a matter for difference of opinion; 
but, though in some parts of the world the sedimentary rocks 
represent mainly deposits in interior epicontinental seas, there are 
other parts—the New Zealand area, for example—in which the 
nature of the rocks indicates that the sediments of which they are 
135 
