How to use River-beds in a sentence
More remarkable still, over large tracts of country the water seems disposed to flow away from, rather than to, the river-beds.
As the general level of the country is raised by successive alluvial deposits, the more ancient river-beds become buried, but being still connected with the newer rivers at some point or other, they continue to absorb water.
This underground network of old river-beds underlying the great alluvial plains must be filled to repletion before flood waters will flow over the surface.
Its northern boundary is the Kuma-Manych depression, a succession of narrow, halfdesiccated lakes and river-beds, only temporarily filled with water and connecting the Manych, a tributary of the Don, with the Kuma, which flows into the Caspian.
The river beds contain dangerous quicksands.Advertisement
This interruption, due to the practical prohibition of the industry by the United States courts, on the ground that it was injuring, through the deposit of tailings, agricultural lands and navigable streams, was lessened, though not entirely removed, by compromises and regulations which permit, under certain restrictions, the renewed exploitation of the ancient river-beds by the hydraulic method.
In working auriferous river-beds, dredges have been used with considerable success in certain parts of New Zealand and on the Pacific slope in America.
The Silurian system is represented by the Baton river beds to the west of the Aorere beds, occurring in the basin of the Motueka river, which flows into Tasman Bay.
In South Island the river-beds of Otago province have been successfully worked by means of dredges, and good returns secured.
The river beds are generally 4 0 to 80 ft.Advertisement
Sometimes in silty river beds they are sunk ioo ft.
In the river-beds, however, and at some distance from the sea, older strata and eruptive rocks underlie the alluvium.
Since the heavy minerals of the cascalho in the river beds are more worn than those of the terraces, it is highly probable that they have been derived by the cutting down of the older river gravels represented by the terraces; and since in both deposits the heavy minerals are more abundant near the heads of the valleys in the plateau, it is also highly probable that both have really been derived from the plateau deposit.
In the latter, especially at Sao Joao da Chapada, the minerals accompanying the diamond are scarcely worn at all; in the terraces and the river beds they are more worn and more abundant; the terraces, therefore, are to be regarded as a first concentration of the plateau material by the old rivers; and the cascalho as a second concentration by the modern rivers.
The country is naturally treeless, except for the tamarisk, which grows by the swamps and along the river-beds.Advertisement
It is also found in the provinces of Loja, Esmeraldas, and in the river-beds along the eastern slopes of the Andes.
From the Kasimiya southwards the maritime plain is crossed by numerous river-beds, with a few exceptions winter torrents only.
Kankar or ghutin (concretionary carbonate of lime) is collected for this purpose from the river-beds and alluvial deposits.
They are mostly bordered by dense vegetation; in the dry season water is found in pools in the river beds or can be obtained by digging.
The results were wonderful but disastrous, for the " dumps " were usually river-beds.Advertisement
Its one large river is the Guadiana, which traverses the north of the province from east to west, fed by many tributaries; but it is only at certain seasons that the river-beds fill with any considerable volume of water, and the Guadiana may frequently be forded without difficulty.
In the outer valleys of the Himalaya the sides are generally steep, so steep as to be liable to landslip, whilst the streams are still cutting down the river beds and have not yet reached the stage of equilibrium.
The Caddis larvae normally live on river-beds, and make cocoons for themselves from bark, gravel and other river detritus.
Thus skeletal elements which have been transported distances along river beds or streams will appear similar to those from heavily reworked deposits.
I built dams of pebbles, made islands and lakes, and dug river-beds, all for fun, and never dreamed that I was learning a lesson.Advertisement