Geology . Fig. 49G.—Drumlins .shown in contour near Clyde, N. Y. (U. S. Geol. Surv.) moraine, though there is often a larger proportion of stratified driftassociated with it. In topography it is somewhat distinctive. It New Jersey, 1902; Lincoln, Am. Jour. Sci., Vol. XLIV (1892), pp. 293-6; Tyrrell,Bull. Geol. Soc. Am., Vol. I (1890), p. 402; Barton, Am. Geol., Vol. XIII (1894), ; Frank Leveret t, Monogrs. XXXVIII and XLI, U. S. Geol. Surv., and Russell,Amer. Ceol., Vol. XXXV (lr05), p. 177. THE PLEISTOCENE OR GLACIAL PERIOD. 363 sometimes constitutes a more or less well-defined ridge, th
Geology . Fig. 49G.—Drumlins .shown in contour near Clyde, N. Y. (U. S. Geol. Surv.) moraine, though there is often a larger proportion of stratified driftassociated with it. In topography it is somewhat distinctive. It New Jersey, 1902; Lincoln, Am. Jour. Sci., Vol. XLIV (1892), pp. 293-6; Tyrrell,Bull. Geol. Soc. Am., Vol. I (1890), p. 402; Barton, Am. Geol., Vol. XIII (1894), ; Frank Leveret t, Monogrs. XXXVIII and XLI, U. S. Geol. Surv., and Russell,Amer. Ceol., Vol. XXXV (lr05), p. 177. THE PLEISTOCENE OR GLACIAL PERIOD. 363 sometimes constitutes a more or less well-defined ridge, though thisis not its most distinctive feature, since its width is generally great,relative to its height. A moraine 50 or even 100 feet high and a milewide is not a conspicuous topographic feature, except in a regionof unusual flatness. In such situations terminal moraines some-times constitute important drainage divides. The most distinctive feature of a well-developed terminal moraine. Fig. 497.—Terminal moraine topography near Oconomowoc, Wis. (Fenneman.) does not lie in its importance as a topographic feature, but in the detailsof its own topography. Its surface is often characterized by hillocksand hollows, or by interrupted ridges and troughs, following one anotherin rapid succession, and without apparent order in their arrangement(Figs. 497 and 498). The hollows and troughs are often without out-lets, and are frequently marked by marshes, ponds, and lakes where-ever the material constituting their bottoms is sufficiently imperviousto retain the water falling and draining into them. The shape andabundance of round and roundish hills, and of short and more or lessserpentine ridges, often closely huddled together, have locally givenrise to such descriptive names as the knobs, short hills, etc. 364 GEOLOGY.
Size: 1859px × 1344px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublishe, booksubjectgeology
