THE METAMORPHIC LIMESTONES OF COMMON- 

 WEALTH BAY, ADELIE LAND. 



i 



BY 



('. E. TILLEY, B.Sc. 



WITH TWO PLATES. 



PA1IK. 



CONTENTS. 



I. Introduction 231 



1 1 . Petrography : 



1. Forsterite- Marbles 232 



2. Tremolite-Marhles 234 



3. Diopside-Tremolite- Marbles 235 



4. Pyroxene-Garnet-Marbles 230 



."). Pvroxene-Epidote-Marbles 237 



<i. Epidote-Marbles 238 



7. Carbonate-free Calc-silicate Rocks 239 



III. Review of the Metamorphic Processes involved 240 



IV. Paragenesis 242 



V. Explanation of Plates ... --Ml 



I. iXTHonrrnnx. 



Tin; group of rooks which are described below represent a collection of erratics made 

 from tin- moraines at Cape Denison, Adelie Land. With reference to their occurrence, 

 ! ><>uglas Mawson states (*) : 



"None of them were met in situ; but tin- evidence of their occurrence in 

 ciTtJiin moraines (their distribution), and the evidence of the rock types which do 

 actually outcrop in situ on that coast of Adelie Land, point to the calc-silicate 

 M-ries being located under the ice Cap to the south-west of Cape Denison, probably 

 in the depression at the head of Commonwealth Bay, between C'ape Denison ;uul 

 Cape Hunter. This is rendered more likely, since this calc-silieat series would 



1 Penonil communication. 



