एक या कम स्तर की भूमि की सतह क्रस्टल आंदोलनों द्वारा अनिर्धारित क्षरण के एक उन्नत चरण का प्रतिनिधित्व करती है

Noun:

समप्राय भूमि, एक कटिबंध जो लगभग पूरा चौरस मैदान है, पेनिप्‍लेन,

peneplain's Usage Examples:

The northern section of the Great Plains, north of latitude 44, including eastern Montana, north-eastern Wyoming and most of the Dakotas, is a moderately dissected peneplain, one of the best examples of its class.

The erosion of the region must have been far advanced, perhaps practically completed, in very ancient times, for the even surface of the peneplain is overlapped by fossiliferous marine strata of early geological date (Cambrian); and this shows that a depression of the region beneath an ancient sea took place after a long existence as dry land.

The piedmont belt may be described as a maturely dissected peneplain over much of its extent; it is indeed one of the best examples of that class of forms. Its uplands are of fairly accordant altitude, which gradually decreases from 500 to 1000 ft.

The height and massiveness of the mountains decrease to the south-west, where the piedmont belt sweeps westward around them in western Georgia and eastern Alabama Some of the residual mountains hereabouts are reduced to a mere skeleton or framework by the retrogressive penetration of widening valleys between wasting spurs; the very type of vanishing forms, Certain districts within the mountains, apparently consisting of less resistant crystalline rocks, have been reduced to basin-like peneplains in the same time that served only to grade the slopes and subdue the summits of the neighboring mountains of more resistant rocks; the best example of this kind is the Asheville peneplain in North Carolina, measuring about 40 by 20 m.

When the peneplain was uplifted the weaker strata were worn down almost to a lowland of a second generation, while the resistant sandstones, of which there a1~- three chief members, retained a great part of their new-gained altitude in the form of long, narrow, even-crested ridges, well deserving of the name of Endless Motintains given them by the Indians, but here and there bending sharply in peculiar zigzags which give this Alleghany section of the mountains an unusual individuality.

The peculiar configuration of thr~ ridges may be apprehended as follows: The pattern of the folded ~trata on the low-lying Cretaceous peneplain must have resembled the pattern of the curved grain of wood on a planed board.

To the east and north-east of the Bitterroot Mountains is a considerable basin or peneplain dissected by short ranges having a northwest and south-west trend.

' In some localities it is not easy to establish irrefutably and in detail the inter-arrangement of drainage and rock structure that proves it to be a subaerial peneplain instead of an uplifted submarine platform; but the general proof is very clear.

By a re-elevation of a peneplain the rivers of an old land surface may be restored to youthful activity, and resume their shaping action, deepening the old valleys and initiating new ones, starting afresh the whole course of the geographical cycle.

In the nature and position of the upland rocks - mainly crystalline schists and gneisses, excessively complicated and disordered in mass, and also internally deformed - there is found abundant proof that the peneplain is a degraded mountain region.

peneplain's Meaning':

a more or less level land surface representing an advanced stage of erosion undisturbed by crustal movements

Synonyms:

field, plain, peneplane, champaign,

Antonyms:

cheer, adorned, pretentious, fancy, complex,