rift

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rift

1
Geology a long narrow zone of faulting resulting from tensional stress in the earth's crust

rift

2 US
1. a shallow or rocky part in a stream
2. the backwash from a wave that has just broken

Rift

 

a major linear tectonic structure of the earth’s crust hundreds and thousands of kilometers long that forms when the crust is horizontally extended; this process usually occurs where there is a vast arching uplift. It is believed that the entire thickness or a significant part of the thickness of the earth’s crust is being extended.

A rift consists mainly of a series of fractures, among which faults with inclined surfaces predominate; the crustal sector lying above the surface of a fault is also dislocated downward. The sum of the horizontal components of all such shifts compensates for the horizontal extension of the crust. The dip of a fault is usually 60°-70°, and the vertical amplitude of the shift along a fault may reach 5 km. The crustal extension can be several kilometers, and in some cases, several tens of kilometers long.

Various types of grabens and horsts are found within a rift. The graben is the chief structural form. A rift usually begins to form, however, with a gentle upward bend of the crust in the form of a tectonic arch; the arch later breaks up and separates into grabens and horsts. Very large rifts are called rift zones or systems.

V. V. BELOUSOV

rift

[rift]
(geology)
A narrow opening in a rock caused by cracking or splitting.
A high, narrow passage in a cave.

rift

The direction in which stone splits most readily; characteristic of granite or other stone not having visible stratification or foliation.
References in classic literature ?
The first observations had not discovered these rifts.
I like," retorted Michel Ardan, "to explain what you savants cannot explain; at least my hypotheses has the advantage of indicating why these rifts disappear, or seem to disappear, at certain seasons.
Bid thy people pass to the right and to the left of me, and stand in all their numbers upon the slopes of the grass that run down to the lips of the rift.
Slowly, and with much pain, he clambered to the bottom of the rift and stood there.
As he spoke the multitude of the people on either side of the rift surged forward like a wave, surged back again, once more surged forward, then, with a dreadful crying, driven on by the merciless spears of the soldiers, they began to fall in a torrent of men, women, and children, far into the black depths below.
When they heard of the bet, my sister, the people of the Langeni hurled themselves into the rift by thousands, being eager to put the matter to the proof.
The narrow canyon turned and twisted this way and that, and the rift was so small that they were able to touch both walls at the same time by stretching out their arms.
As he stood looking down upon this grim reminder that another man of might had succumbed to the cruel powers of the desert, he was brought to startled attention by the report of a firearm, the sound of which came from the depths of the gorge to the south of him, and reverberated along the steep walls of the narrow rift.
Suddenly, as he spoke, a great brightness fell about him, causing him to look upward, thinking the sun had burst through a rift in the clouds; but there were no clouds.
Presently Tibo saw a faint lightness ahead of them, and a moment later they emerged into a roughly circular chamber to which a little daylight filtered through a rift in the rocky ceiling.
Through the narrow rift in the rocky roof above him, Tibo could see a few stars, and once the moon crossed.
Through a rift in the mist, he caught a glimpse of the brown sail of a fishing-boat, dangerously near the land.