释义 |
overˈdeepen, v. Geol. [over- 22; overdeepening is tr. G. übertiefung (A. Penck 1899, in Verhandl. des 7en Internat. Geographen-Kongr. (1901) II. 232).] trans. To deepen further, to make even deeper. So over-ˈdeepened ppl. a., -ˈdeepening vbl. n.
1900Proc. Boston Soc. Nat. Hist. XXIX. 308 Penck has suggested that glaciated valleys of the Alpine kind should be called ‘overdeepened’. 1902Q. Jrnl. Geol. Soc. LVIII. 703 The hanging valleys in the lower part of the Val Ticino are attributed to the overdeepening of the main valley by ice. 1905Jrnl. Geol. XIII. 392 As soon as a shallow wind-blown hollow is formed, that part of the integrated drainage system which leads to the hollow will supply waste to it whenever rain falls there;..the coarser waste will accumulate, and thus the tendency of the winds to overdeepen local hollows will be..counteracted. 1913Bull Geol. Soc. Amer. XXIV. 214 Similarly, a valley glacier, while actively overdeepening its trough, might develop a more or less abrupt step in the trough floor. 1968R. W. Fairbridge Encycl. Geomorphol. 327/1 Regardless of whether the overdeepening of the river mouth is primarily due to eustatic rise of sea level or tectonic subsidence, it is said to be a drowned valley. Ibid. 743/2 The rock floors of overdeepened troughs remain bare in parts. Ibid., Overdeepening is responsible for the production of numerous lakes, some of very large size. 1970C. A. Lewis Glaciations Wales ii. 25 The major through-valleys of Snowdonia were overdeepened and straightened at this time by lowering of the watersheds by ice moving radially outwards from a centre near Llyn Tegid. |