ORIGINAL ARTICLES. 
Precambrian Para-Gneisses of Southern Eyre 
Peninsula, South Australia. 
By C. E. Tintey, Emmanuel College, Cambridge. 
(PLATE. III.) 
CONTENTS. 
1. Introduction. 
2. The Sleaford Bay Section. 
3. The Garnet Gneisses. 
(a) General Description. 
(b) Petrography. 
Origin of the Garnet Gneisses. 
Summary. 
1. INTRODUCTION. 
N an earlier paper! a description of certain dolomites and cale- 
magnesian silicate rocks of the oldest group ‘recognized in 
southern Eyre Peninsula—the Hutchison series—has been given. 
Intimately associated and interbanded with these dolomites occur 
a group of garnet gneisses along the shores of Sleaford Bay. A 
portion of the section exposed in this place was figured in the paper 
referred to. 
‘The present notes are devoted to a description of these 
garnetiferous gneisses exposed at Sleaford Bay, together with a 
short account of some similar gneisses developed in the Hutchison 
area to the north. 
our 
2. THE SLEAFORD Bay SEcTION. 
To the section already given in the previous communication a 
second is now added (Fig. 1 of the present paper). This section 
represents a continuation of the rocks exposed in an easterly 
Fic. 1.—Section along the shore at Sleaford Bay. 
St 350 yards a 
er = granite, agr =aplitic gneiss, di = diopside rock, ms = mica schist, 
f = ironstone band, ggn = garnet graphite gneiss, hr = hornblende schist, 
gn = garnet gneiss, y = ? kaolinized schists with pegmatite veins. 
direction. A number of beds forming the eastern extremity of the 
first section are again inserted in the accompanying diagram. The 
total length of section now revealed is approximately half a mile. 
1 ©. E. Tilley, Grou. Mac., Vol. LVII, 1920, pp. 449-62, 492-500. 
