The process by which small particles of fine soils and sediments aggregate into larger lumps.
Of or pertaining to the sea; -- sometimes applied to rocks formed from sediments deposited upon the sea bottom.
In the Rockies there are coarse sediments miles deep, together with limestone formed of the ground-up shells of marine animals of the earlier times.
There were land animals, too, that got buried in the accumulating sediments and fossilized.
But doesn't the ocean give it back to the land when it leaves these sedimentsalong the shore?
If this view is well founded, lavas and other igneous rocks are in large part fused argillaceous sediments formed in connection with the process of folding, or are refused rocks of igneous origin and similar composition.
Here it is evident that the sedimentswhich compose the lower series of beds have been folded in the zone of flow, though the upper series has evidently escaped this vicissitude.
This gorge has been cut in beds of rock sediments which dip at a gentle angle southward toward Lake Erie.
The tabular classification of the sediments is as follows:— Classification of Sediments.
Of all the processes which conspire to blot out the lakes with which our northern landscapes are dotted, the one of greatest importance is in most cases a process of filling by the sediments brought in by tributary streams.
Diagram to show the order of the sediments laid down during a transgression of the sea.
With a deceptive unconformity the clew to its real nature is usually some fact which indicates that the lower series of sediments had been raised above the level of the sea before the upper series was deposited upon it.
Clay deposits surrounded by coarser sediments are thus characteristic of filled lake basins.
The lime carbonate is usually derived from the hard parts of marine organisms, and the argillaceous and siliceous impurities from the finer land-derived sediments which descend with them to the bottom.
When subjected to long-continued erosion, the generally fissured granitic core of the laccolite weathers in a wholly different manner from the bedded sediments which surround and still in part mount over it.
If glacier-derived material is taken up by the streams of thaw water and is by them redeposited, the sediments are assorted or stratified, and they are described as fluvio-glacial deposits.
All the knowledge we have of the subject justifies the inference that most of the igneous rocks which have been poured out in our Western Territories are but fused conditions of sediments which form the substructure of that country.
The question is of the age of the sediments from which these were taken.
Clastic sediments are less abundant and there are fewer breaks in the succession.
It continued to settle during the next geological period of millions of years, and layer after layer of sediments were washed in and deposited on top of it.
These sediments contained huge amounts of volcanic ash which the streams apparently picked up near their sources.
The deposition of these sediments over the plain continued until a layer about 400 feet thick was built up during the centuries.
It is the slow sinking of the region which has made possible great accumulations of sediments and the building up of rock layers.
It seems more probable, however, that the Grand Canyon region was above sea level during these two ages so that no sediments were accumulated and consequently no rocks formed.
Temple Butte Limestone Devonian Age h~ Sand, muds, and limes representing ancient beach which was gradually covered with water until finally the sediments were at a considerable depth beneath the sea.
Occurrence of Triassic Sediments on the Rim of Grand Canyon: Jour.
All are rocks formed by the deposition of sediments by wind and water during vast intervals of time.
Around and against these, sediments were then deposited.
Great accumulations of vegetable matter, buried beneath sediments brought down by streams, eventually formed the many layers of coal which today are found in various places in Utah, Arizona, and New Mexico.
For long ages this region has been above the level of the sea, erosion has been continuous, sosediments have not accumulated and consequently few records of life have been made.
Today these sediments appear in the Grand Canyon walls as alternating layers of red sandstone and shale immediately above the great Redwall.
Zen has no business with the dregs and sediments of sages of yore.
Out of dirty sediments the mountains, the four continents, the hells, oceans, and outer ring of mountains, were made.
The facts above presented will show the reader that the marine sediments are formed under conditions which permit a great variety in the nature of the materials of which they are composed.
In most cases, however, the cutting action of the streams has been sufficient to bring the drainage channels down to the bottom of the trough, while the influx of sediments has served to further the work by filling up the cavities.
When sediments are laid down on the sea floor the materials consist of small, irregularly shaped fragments, which lie tumbled together in the manner of a mass of bricks which have been shot out of a cart.
During the periods when it was above sea level, the higher land was eroded, and the sediments deposited at a lower level.
Between the periods of deposition were intervals when the land was relatively high, and in certain areas all of the sediments of an earlier period were eroded away.
Most of the rocks within the area around the Black Hills are composed of sediments deposited by water.
Near the end of the Cretaceous period, the sea made its final withdrawal, and the sediments from late Cretaceous time to the present were deposited in fresh water.
The Missouri Buttes and Devils Tower were intruded directly through horizontal sediments without disrupting them, even in the immediate vicinity of the igneous bodies.
Nearly all the ridges we had crossed which extended from north-east to south-west were well rounded--fairly well padded with sediments of earth, sand and ashes.
These accumulations or sediments now stood up at an angle of 45°.
The Nile, the Colorado, and the Yellow are exotic rivers that flow through deserts to deliver their sediments to the sea.
Fossil desert sedimentsthat are as much as 500 million years old have been found in many parts of the world.
The earliest known sediments must have been deep in the zones of shearing and rock flowage before the first pre-Cambrian denudation.
In order to make use of these old sediments as measures of time it is necessary to know either their thickness or their volume, and also the rate at which they were laid down.
The rocks which were formed as sediments show many traces of rhythm.
The increase of glaciers in one hemisphere would not only modify adjacent sediments directly, but, by adding matter on that side, would make a small difference in the position of the earth's center of gravity.
It is true we here assume the radioactivity of the sediments 129 and of the normal crust to be the same.
The fact that the yielding of the crust is always situated where the sediments have accumulated to the greatest depth, has led to attempts from time to time of establishing a physical connexion between the one and the other.
Observation on the landsediments shows that the calcareous rocks amount to about 5 per cent.
The sediments are, however, less radioactive in the proportion of 4 to 3.
And if a foundered range is exposed now to our view encumbered with thousands of feet of overlyingsediments we know that while the one range was sinking, another, from which the sediments were derived, surely existed.
To them the great accumulations of sediments which now form so large a part of continental land are mainly due.
Its high value in the sediments is due to its restoration from the ocean to the land.
We are, 46 thus, able to amend our estimate of the sediments which, as determined by direct observation, served to support the basis of our argument.
To these now succeeded Upper Chalk, sediments of Danian age, and so on, till Eocene times, when the tale was completed and the existing ranges rose from the sea.
While above the folded sediments are being carried northward, beneath they are becoming anchored in the growing viscosity of the medium.
Defn: The process by which small particles of fine soils and sediments aggregate into larger lumps.
Defn: Of or pertaining to the sea; -- sometimes applied to rocks formed from sedimentsdeposited upon the sea bottom.
Arches National Park and most of nearby Canyonlands National Park lie within what geologists have termed the "Paradox basin," which contains a remarkable assemblage of sediments called the Paradox Member of the Hermosa Formation.
Salt differs from normal sediments in two properties critical to the development of salt anticlines: first, salt is considerably lighter (fig.
Following Paradox time, normal sediments derived from a rising landmass to the northeast began to fill the basin.
Once started, this process tended to be self-perpetuating, as the flow of salt from beneath the thick masses of sediments in the troughs made room for the accumulation of still greater thicknesses of normal sediments.
Thus, salt in the troughs underlying the thicker and heavier masses of sediments was squeezed into the adjoining ridges, causing them to rise.
These sediments accumulated most rapidly and to greater thicknesses in the fault-derived troughs.
How the Canyons Were Formed Some 200 million years ago this region lay under a sea whose sediments formed the structural, limestone bedrock patterns of the Big Bend.
Illustration: ② Streams erode the mountains and begin to deposit sedimentsin the valley.
The Laurentian Rocks constitute the base of the entire stratified series, and are, therefore, the oldest sediments of which we have as yet any knowledge.
Sediments of this series occupy extensive areas in Great Britain, on the continent of Europe, and in India.
Red rocks are, as a general rule, more or less completely unfossiliferous, and sediments of this nature are highly characteristic of the Permian.
Whenever muddy sediments are found in the Cambrian and Silurian formations, there we are tolerably sure to find Trilobites, though they are by no means absolutely wanting in limestones.
In fact, the former of these last-mentioned deposits contains no fossils which can be asserted positively to be marine (unless the Eurypterids be considered so); and it is even conceivable that it represents the sediments of an inland sea.
In general, the sedimentsare sandy and calcareous in the Juratrias area, and sandy in the Catoctin Belt.
In regions where no sediments occur, the relation of the schistose planes to the folds can not be discovered.
In all cases they are closely parallel to the planes on which the sediments moved in adjustment to folding, namely, the bedding planes.
Productiveness is in a great measure maintained by the addition of the sediments left by the overflow waters.
Macroscopically it is evident in the strong schistosity, which is parallel to the structural planes of the sediments when the two are in contact.
All along the watercourse extensive sediments of salt lined the edge of the water, and higher up, near the mountains, the water is said to be actually bridged over by salt deposits several inches thick.
We continued, and entered a broader valley, also of volcanic formation, with reddish sediments burying a sub-formation of yellowish brown rock which appeared in the section of the mountains some 300 feet above the plain.
The summit is actually concave, like a basin, with numerous hillocks all round, and one portion, judging by sediments left, would appear to have contained a lake.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "sediments" in a variety of sentences. We hope that you will now be able to make sentences using this word.
