Page images
PDF
EPUB
[subsumed][subsumed][subsumed][ocr errors][subsumed][subsumed][ocr errors][subsumed][subsumed][subsumed][ocr errors][subsumed][subsumed][subsumed][subsumed][subsumed][ocr errors][subsumed][subsumed][ocr errors][subsumed][subsumed][subsumed][subsumed][subsumed][ocr errors][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][subsumed][merged small][subsumed][subsumed][merged small][graphic]

The Geology of Newport, Troy and Coventry.

C. H. RICHARDSON, SYRACUSE UNIVERSITY.

INTRODUCTION.

The present report upon the Geology of Newport, Troy and Coventry, Vermont, is of necessity brief. It must be considered only as one of progress. A few weeks in the summer of 1907, together with an equal amount of time in June, 1908, comprise all the time that has been available for the study of the field relations, the mapping of the area involved, and the collection of typical museum specimens. This amount of time has proven even too limited for the scaling of every hill and the discovery of all possible exposures.

The area chosen comprises three townships in the northern part of Orleans County, west of Lake Memphremagog and south of the International boundary. Some work has also been done in Derby, Brownington, Barton, Irasburgh, Jay and Westfield. I am in hope that enough field work can be accomplished within the following two years to enable me to complete an article upon the geology of the entire county for the next report of the State Geologist.

Several photographs have been taken, a part of which appear as half-tones in this article, while the others are reserved for future illustrations. One hundred and eleven new rock specimens have been collected in the field from northeastern Vermont, carefully trimmed to standard uniform size, 3 x 4 inches, making three hundred and thirty-three specimens, and placed on exhibition in the State Museum at Montpelier. These specimens represent a series of very important rocks of widely different ages, mode of origin and chemical composition. When the series is made complete it will form a valuable educational factor in illustrating the geology of eastern Vermont.

Two maps accompany this report. One is stratigraphical, representing a protracted section across Newport, Troy and Coventry.

[graphic][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small]

The other shows the geographical distribution of the terranes within the same area. The stratigraphical map reveals the dip of the strata whose planes of cleavage do not always coincide with the planes of bedding. No bibliography is herein given because a complete bibliography was printed in the Fifth Report of the Vermont State Geologist, 1906.

I wish also to recognize my great indebtedness to Prof. John A. Dresser, McGill University, Montreal, for his timely assistance in the study of these rocks in better developed Canadian territory, in the Black Lake district northeast of Sherbrooke; to the Canadian survey for effecting arrangements for international coöperation in the work of the two surveys most deeply interested in the problems; and to Burton W. Clark, a graduate student in Syracuse University, for his companionship and aid in working out numerous details in the field for twelve days in June, 1908.

DRAINAGE.

With the height of the land twenty-five miles south of the international boundary, the drainage of the area described in this report is naturally to the north.

Barton River, with its head waters in Crystal Lake in Barton, flows through the eastern part of Coventry and empties into Lake Memphremagog. Along this river the Passumpsic division of the Boston. and Maine Railroad threads its sinuous way into Newport, where it makes connection with the Canadian Pacific Railroad for Montreal.

The Black River rises in Craftsbury and flows northward through Irasburgh, Coventry and Newport into Lake Memphremagog. As will be seen in the discussion of the geology of the area, each of these streams lies in a bed of limestone with a belt of slate, hard and pyritiferous, rising to a much higher altitude between the valleys.

The third river of noteworthy dimensions is the Missisquoi. The source of this stream is amongst the mountains of Lowell. It is fed also by numerous branches from the western slope of the Green Mountains in Jay and Westfield. In its northward course through Troy it furnishes some of the best water powers of the state. Great Falls on this river, about two miles south of North Troy, furnishes an excellent example of such power. Through this valley there is also an easy outlet for the proposed Mount Orford Railroad in its

« PreviousContinue »