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SOME RIVERS OF CONNECTICUT.[1]
Outline.—Introduction.—Topography of Connecticut: The upland plateau, its origin, date, elevation, valleys sunk beneath its surface.—Lowland on the Triassic area.—Later oscillations.—Résumé of the topography.—Early drainage.—Re-adjusted streams.—Revived streams.—Unconformable rivers, consequent or superimposed.—Pleistocene changes; the Farmington, Quinnipiac, Scantic.—Abandoned gaps.
Introduction. In order to study intelligently the history of a river, one must first become acquainted with the present physical geography of the region in which the river lies, and know the stages of its development. Therefore, before classifying the rivers of Connecticut, I shall consider the topography of the state, and in a few paragraphs outline the successive cycles in the history of its growth. The scope of this article will not permit a discussion or even a full statement of the evidence on which these conclusions are based. They have been stated at considerable length by Professor W. M. Davis,[2] and the reader is referred to his papers for the complete discussion. His conclusions in respect to the physical geography are accepted here without question, and form the basis for the discussion on the rivers of the state.
Topography of Connecticut. Connecticut can be said to consist of two great areas quite distinct in topography and geologic structure.[fig 1] On the east and on the west are the crystalline uplands which rise from sea level along the Sound to 1,700 and 1,800 feet in the northwestern part of the state, and to 600 and 700 feet in the northeastern. These uplands consist chiefly
- ↑ The author desires to express his obligation to Professor W. M. Davis for aid in the preparation of this article. It was first written under his direction and with the help of his suggestions when the author was in the graduate school of Harvard University. Prof. Davis is not responsible, however, for the statement of the views herein advanced, although in general it is believed that he is in accord with them.
- ↑ Amer. Jour. Sci. 3d ser., vol. xxxvii, 1889, p. 423.Bull. Geol. Soc. Amer., vol. ii, p. 545.
- ↑ The rough diagrams accompanying this paper may aid the reader who is unacquainted with the details of the region under discussion. The abbreviations on the above figure are as follows: C. The Connecticut. Cr. Pl. Crystalline plateau (the shaded area). F. The Farmington. H. Hartford. Ho. The Housatonic. Lm. Limestone area. M. Meriden. Mi. Mill River. Mt. Middletown. N. The Naugatuck. N. H. New Haven. No. The Norwalk. Q. The Quinnipiac. Qg. The Quinnebaug. S. The Scantic. Sa. The Saugatuck. T. Tariffville. Th. The Thames. The unshaded area is the Triassic sandstone lowland, and the blackened areas represent the ridges of the faulted trap sheets.
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