GEOLOGICAL FEATURES OF ST, CROIX RIVER 109 
SESSIONAL PAPER No. 38a 
THE GEOLOGICAL FEATURES OF THE ST. CROIX RIVER AND PASSAMA- 
QUODDY BAY. 
By L. W. Baitey, LL.D., Ph.D., F.R.S.C., etc., Hmeritus Professor of Natural History 
and Geology, University of New Brunswick. 
(With map.) 
Of those who visit the Biological Station at St. Andrews, whether as tourists 
or as members of the staff and participants in its work, there are many who, attracted 
by the unusual beauty of its surroundings, would like to know something of the causes 
to which that beauty is due. I have therefore been asked by members of the Biologi- 
cal Board to prepare a short sketch of the geological features of the region. These, 
of course, are fully detailed in the reports of the Canadian Geological Survey, but 
are contained in many different volumes, and are not always easily accessible and 
are so associated with the geology of wider areas as to make it somewhat difficult to 
obtain the desired facts. In this sketch only those are given which seem to be of 
general interest. 
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The region under review is naturally divided into three sections. Of these, the 
first is the St. Croix river proper, a wholly fresh water stream having its sources in 
connection with considerable lakes north and west of Vanceboro, and thence flowing 
in a southerly direction to meet the second section at the falls in St. Stephen. The 
volume of water, though sufficient for lumbering and milling purposes, does not pro- 
duce any appreciable effect on the salinity or density of the water in this second 
section. 
The latter may be called the St. Croix estuary, and extends from the head of 
tide-water at the falls in St. Stephen to the vicinity of St. Andrews, where it gradu- 
ally widens out into Passamaquoddy bay. Through this and the preceding section, 
it constitutes a part of the international boundary. The third section is that of 
Passamaquoddy bay itself, an area about eleven miles wide by seven, and imperfectly 
separated by the chain of the Western Isles, from the waters of the Bay of Fundy. 
As regards the geological features of these several areas, the first needs but little 
consideration here. North of MacAdam Junction the rocks are mainly granite, 
boulders of which in great numbers, and often of very large size, thickly strew the 
tract surrounding and south of that railway centre. Further south the river traverses 
two wide belts of slates, of which the more northerly are pale of colour and carry 
obscure organic remains, appearing to indicate a Devonian age, while the more 
southerly are darker, and though yielding no fossils, are believed to be Cambro- 
Silurian. Through these, at many points, protrude small bosses of granite, which 
about St. Stephen become more considerable. Near the town last named they con- 
tain large bands of diorite and serpentinous rocks containing considerable bodies of 
pyrrhotites like those of Sudbury, Ont., which they closely resemble, and carry ores 
of nickel, though the percentage of the metal, so far as at present known, is too small 
to admit of profitable extraction. 
