n. (context geology English) one of the major groups of rock that makes up the crust of the Earth; formed by the deposition of either the weathered remains of other rocks, the results of biological activity, or precipitation from solution
n. rock formed from consolidated clay sediments
Sedimentary rocks are types of rock that are formed by the deposition and subsequent cementation of that material at the Earth's surface and within bodies of water. Sedimentation is the collective name for processes that cause mineral and/or organic particles ( detritus) to settle in place. The particles that form a sedimentary rock by accumulating are called sediment. Before being deposited, the sediment was formed by weathering and erosion from the source area, and then transported to the place of deposition by water, wind, ice, mass movement or glaciers, which are called agents of denudation. Sedimentation may also occur as minerals precipitate from water solution or shells of aquatic creatures settle out of suspension.
The sedimentary rock cover of the continents of the Earth's crust is extensive, but the total contribution of sedimentary rocks is estimated to be only 8% of the total volume of the crust. Sedimentary rocks are only a thin veneer over a crust consisting mainly of igneous and metamorphic rocks. Sedimentary rocks are deposited in layers as strata, forming a structure called bedding. The study of sedimentary rocks and rock strata provides information about the subsurface that is useful for civil engineering, for example in the construction of roads, houses, tunnels, canals or other structures. Sedimentary rocks are also important sources of natural resources like coal, fossil fuels, drinking water or ores.
The study of the sequence of sedimentary rock strata is the main source for an understanding of the Earth's history, including palaeogeography, paleoclimatology and the history of life. The scientific discipline that studies the properties and origin of sedimentary rocks is called sedimentology. Sedimentology is part of both geology and physical geography and overlaps partly with other disciplines in the Earth sciences, such as pedology, geomorphology, geochemistry and structural geology. Sedimentary rocks have also been found on Mars.
Usage examples of "sedimentary rock".
But to geologists and palaeontologists this land of sandstones and shales, piled up into the tablelands the Afrikaners called koppies, was one of the Earth's greatest storehouses: a thousand-mile slab of sedimentary rock that was the best record on Earth of land-animal evolution.
The ground here is some kind of sedimentary rock with granite boulders embedded in it from place to place, like mixed nuts in half-melted chocolate.
His eyes roamed over the landscape, taking in every detail: the columnar basaltic escarpment a mile away, the double-throated volcanic plug, the unusual outcropping of sedimentary rock.
Granite is an igneous rock, which wells up from the molten layers beneath the Earth's crust, forcing a path through the overlying sedimentary rock that has been deposited by wind or water.
The seasonal streams end rivers fed by glacial melt cut through the deep loess, and often through the sedimentary rock to the crystalline granite platform underlying the continent.
In any sequence of undisturbed sedimentary rock strata, the oldest rocks are on the bottom, with the younger ones stacked successively atop them.
The occasional highlands that noted the central plain were connected, though partly sub- neath the soil in the midland basin, to great broken blocks sedimentary rock running in an irregular backbone from to southwest through the plain.
The preponderance of sedimentary rock in this area, she knew, was due to the Chuun River, which flowed from here all the way down to Axis Tyr, the Kundalan city the V'ornn had chosen as their capital.
Except for the igneous outcropping in which the mine is located, this whole valley is sedimentary rock, probably for a depth of several hundred feet.
Seismic wave studies had led the scientists to predict, and pretty confidently, that they would encounter sedimentary rock to a depth of 4,700 meters, followed by granite for the next 2,300 meters and basalt from there on down.
The cliffs behind the town were nominally of sedimentary rock, but any geologist would have taken one look and told you at once that these rocks were to the sedimentary classification as the nouveau riche were to the Four Hundred.
As a result, the level of carbon dioxide stored in sedimentary rock is now more than six hundred times the total carbon content of the planet's air, water, and living cells combined.
The sedimentary rock record was deposited by the Flood and it is all essentially the same age.
But in some sedimentary rock, the diamond foram layer was hundreds of feet thick.