Crossword clues for craton
Wiktionary
n. A part of the Earth’s crust that has survived the splitting and merging of continents.
WordNet
n. the part of a continent that is stable and forms the central mass of the continent; typically Precambrian
Wikipedia
A craton (, , or ; from kratos "strength") is an old and stable part of the continental lithosphere, where the lithosphere consist of the earth's two topmost layers, the crust and the uppermost mantle. Having often survived cycles of merging and rifting of continents, cratons are generally found in the interiors of tectonic plates. They are characteristically composed of ancient crystalline basement rock, which may be covered by younger sedimentary rock. They have a thick crust and deep lithospheric roots that extend as much as several hundred kilometres into the Earth's mantle.
The term craton is used to distinguish the stable portion of the continental crust from regions that are more geologically active and unstable. Cratons can be described as shields, in which the basement rock crops out at the surface, and platforms, in which the basement is overlaid by sediments and sedimentary rock.
The word craton was first proposed by the Austrian geologist Leopold Kober in 1921 as , referring to stable continental platforms, and orogen as a term for mountain or orogenic belts. Later authors shortened the former term to kraton and then to craton.
Examples of cratons are the North China Craton, the Sarmatian Craton in Russia and Ukraine, the Amazonia Craton in South America, the Kaapvaal Craton in South Africa, the North American or Laurentia Craton, and the Gawler Craton in South Australia.
Usage examples of "craton".
Once Craton Starbridge, his best friend, had held a ladder to his window, and he had come down in borrowed clothes to be among his people.
In a front-page editorial of the leading opposition daily, Craton Starbridge announced the formation of a new political party, a coalition of reactionary and progressive Starbridge elements, unified by a new political agenda.
But at that moment Craton Starbridge raised his hand, shouting from the back of the rotunda: “My lord, it’s true.
Carelessly Craton Starbridge took the last one from his hands and flipped it over.
Someone shouted something that he didn’t understand, and then he saw Craton Starbridge lurch out of the mist, coming up from below.
Then he saw a single horseman jump over a ridge of earth, carrying the flag of Craton Starbridge and his family, a white ship under sail upon a sea of mist.
Caledonia has nineteen small continents with a single craton for each.
The twelve populated ones were supposed to have cratons that stabilized aeons ago, but as you may know, doubts have been cast on the validity of the original Krondak survey.
The lighter-colored continental regions around the edges and to the north are younger rocks that accreted to the craton throughout the aeons as the landmass slowly grew.
It's nearly three hundred kloms under the sea from the south edge of the Clyde craton to the Sgeirean Dubha island arc.
The old pipe goes clear through the Clyde craton right down to the magma.
When it reached the solid part of the lithosphere, the actual Clyde craton, which was about 35 kloms thick, it was still hot enough to melt the rock in its path and turn it into the stuff called kimberlite.
Or it may be that tectonic forces were still roiling the early crust, and an early protocontinental craton, like Pangaea on Earth, had risen in the southern hemisphere and then hardened into place, as the smaller planet cooled faster than Earth, without any subsequent tectonic-plate breakup and drift.
Or it may be that tectonic forces were still roiling the early crust, and an early proto-continental craton, like Pangaea on Earth, had risen in the southern hemisphere and then hardened into place, as the smaller planet cooled faster than Earth, without any subsequent tectonic plate break-up and drift.
The continents showed up in his images as black and dark islands in glowing oceans, the ancient granite cratons surrounded by crumpled greenstone.