File:The American journal of science (1917) (18149780602).jpg

Title: The American journal of science
Identifier: americanjourna4431917newh (find matches)
Year: 1880 (1880s)
Authors:
Subjects: Science
Publisher: New Haven : J. D. & E. S. Dana
Contributing Library: Smithsonian Libraries
Digitizing Sponsor: Biodiversity Heritage Library

View Book Page: Book Viewer
About This Book: Catalog Entry
View All Images: All Images From Book
Click here to view book online to see this illustration in context in a browseable online version of this book.

Text Appearing Before Image:
352 Spencer— Origin and Age of the Ontario Shore-Line. Fig. 1.
Text Appearing After Image:
Fig. 1. Map and chart in the vicinity of Toronto, showing soundings, etc. (After Chipman and Powers' maps.) *Bull. Geol. Soc. Am., vol. xxvii, due to the scour of its outlet had not been in- vestigated. Between 1911-1914, I found that the terraces at about 15 feet* and 5 feet recur from one end of the lake to the other, thus show- ing that the deformation had ceased when the waters were at these levels. But, as stated before, the water level had been more than 200 feet lower than now be- fore the deformation which barricaded the basin, thereby causing the lake to rise again. The banks of the St. Lawrence River, except at some of the rapids, are composed of drift seldom rising higher than 20 feet, with broad plains beyond formerly covered by a pre-Ontario lake. Where rocky isl- ands, in the upper part of the river, rise higher, deep channels occur be- tween them. These are pre-Gl acial features, while the modern river was first established when it was confined by the terrace about 15 feet above the present sur face, such as may be seen at Gananoque, carved out of banks of drift. This terrace is especially well-defined at Mill Haven (12 miles west of Kingston), being there carved out of shaly rock ; so that the term Mill Haven Terrace m a y approximately be given p. 79, 1916 (abstract).

Note About Images