Red clay sentence example
The limestones contain Globigerina and other Foraminifera, the siliceous beds are made of Radiolaria, sponge spicules and diatoms, while the red clay closely resembles the red clay of the deepest parts of the oceans.
When those deposits of organic origin are wanting or have been removed, the red clay composed of the mineral constituents is found alone.
Thus red clay and radiolarian ooze are distinguished as abyssal deposits in contradistinction to the epilophic calcareous oozes.
Red clay is the deposit peculiar to the abysmal area; 70 carefully investigated samples collected by the " Challenger " came from an average depth of 2730 fathoms, 97 specimens collected by the " Tuscarora " came from an average depth of 2860 fathoms, and 26 samples obtained by the " Albatross " in the Central Pacific came from an average depth of 2620 fathoms. Red clay has not yet been found in depths less than 2200 fathoms. The main ingredient of the deposit is a stiff clay which is plastic when fresh, but dries to a stony hardness.
A very interesting feature is the small proportion of calcium carbonate, the amount present being usually less as the depth is greater; red clay from depths exceeding 3000 fathoms does not contain so much as 1% of calcareous matter.Advertisement
Amongst the foreign material found embedded in the red clay are globules of meteoric iron, which are sometimes very abundant.
The manganese nodules afford the most ample proof of the prodigious period of time which has elapsed since the formation of the red clay began; the sharks' teeth and whales' ear-bones which serve as nuclei belong in some cases to extinct species or even to forms derived from those familiar in the fossils from the seas of the Tertiary period.
This fact, together with the extraordinarily rare occurrence of such remains and meteoric particles in globigerina ooze, although there is no reason to suppose that at any one time they are unequally distributed over the ocean floor, can only be explained on the assumption that the rate of formation of the epilophic deposits through the accumulation of pelagic shells falling from the surface is rapid enough to bury the slowgathering material which remains uncovered on the spaces where the red clay is forming at an almost infinitely slower rate.
Sir John Murray believes that no more than a few feet of red clay have accumulated in the deepest depressions since the close of the Tertiary period.
Radiolarian ooze was recognized as a distinct deposit and named by Sir ' John Murray on the " Challenger " expedition, but it may be viewed as red clay with an exceptionally large proportion of siliceous organic remains, especially those of the radiolarians which form part of the pelagic plankton.Advertisement
This theory accords well with the enormous lapse of time required in the accumulation of the red clay.
Over a large part of the central Pacific, far removed from any possible land-influences or deposits of ooze, the red-clay region is characterized by the occurrence of manganese, which gives the clay a chocolate colour, and manganese nodules are found in vast numbers, along with sharks' teeth and the ear-bones and other bones of whales.
In the Piedmont Plateau and Appalachian Mountains Regions the surface soil is generally sandy, but in considerable areas the subsoil is a red clay derived largely from the decomposition of hornblende.
The body is ornamented with red clay and the lower incisors are often extracted.
In the deeper parts the bed of the ocean is covered on the west and south by Globigerina ooze except for an elongated patch of red clay extending most of the distance from Sokotra to the Maldives.Advertisement
The red clay covers a nearly square area in the eastern part of the basin bounded on two sides by the Sunda Islands and the west coast of Australia, as well as two strips extending east and west from the southern margin of the square along the south of Australia and nearly to Madagascar.
In the northern portion of the square, north and east of Wharton deep, the red clay is replaced over a large tract by Radiolarian ooze.
The red clay is frequently dug for brick-making.
A few of the most important clay rocks, such as china-clay, brick-clay, red-clay and shale, may be briefly described here.
The red-clay is an abysmal formation, occurring in the sea bottom in the deepest part of the oceans.Advertisement
Another type of red-clay is found in caves, and is known as cave-earth or red-earth (terra rossa).
Timber framed, weatherboarded, roofed, with handmade red clay pantiles.
Object Type Watcombe Pottery were proud of their fine red clay and specialized in clean, classical shapes.
Their reliance on the distinctive local red clay makes their production recognizable as coming from Devon or Somerset.
The red clay is the characteristic deposit of the Pacific Ocean, where about ioi,000,000 sq.Advertisement
Several battalions of soldiers, in their shirt sleeves despite the cold wind, swarmed in these earthworks like a host of white ants; spadefuls of red clay were continually being thrown up from behind the bank by unseen hands.
Seek out liners that are rich in earth or red clay tones.