350 C. A. COTTON 



area mapped by McKay' as conglomerate was traversed, and it 

 therefore appears that the outcrop is much smaller than is indicated 

 by McKay's map. The stratigraphy at Kekerangu and Deadman's 

 Hill is much involved, and, if Dr. Thomson's discovery at Dead- 

 man's, already referred to, is excepted, the sections of the con- 

 glomerate there exposed throw little light on its stratigraphical 

 relations. 



The writer has, therefore, studied in greater detail the strip in 

 the Middle Clarence Valley where, especially in the Dee and 

 Mead gorges, the sections are clearer; and the results are presented 

 in the following pages. 



From what has been already said it is clear that our knowledge 

 of the age of the beds is insufficient to warrant the use of the name 

 "Great Post-Miocene Conglomerate" applied by McKay and the 

 formation will therefore be referred to in this paper by the name 

 "Great Marlborough Conglomerate" adopted by Thomson.^ 



CONCLUSIONS AS TO THE NATURE AND RELATIONS OF THE 

 CONGLOMERATE 



Briefly stated, the conclusions as to the nature and relations 

 of the Great Marlborough Conglomerate reached by the writer 

 are as follows: 



1. It exhibits fairly regular stratification, always more or less 

 parallel to that of the underlying series. 



2. Its relation to the underlying series, wherever the junction 

 has been examined, appears to be one of conformity. 



3. It contains, in abundance, masses of rock derived from the 

 underlying formations. 



4. It is, in the main, a fiuviatile deposit. 



The second and third statements, which appear, at first sight, 

 contradictory, may be otherwise stated thus: The conglomerate 

 forms a "superposed series" with the beds on which it rests, but, 

 with an adjoining area of the same beds, which has since been 

 entirely removed by erosion, but which supplied much of the 

 material of the conglomerate, it formed, when first laid down, an 



^Op. cit. {1877), map, p. 188. 



^ J. Allan Thomson, N.Z. Geol. Surv., -jth Ann. Rep., 1913, p. 123. 



