Tectonism definition is the process of deformation that produces in the earths crust its continents and ocean basins, plateaus and mountains, folds of strata, and faults called also diastrophism. Isostasy, ideal theoretical balance of all large portions of earths lithosphere as though they were floating on the denser underlying layer, the asthenosphere, a section of the upper mantle composed of weak, plastic rock that is about 110 km 70 miles below the surface. Lines of criticism of isostasy facts not accounted for by the type of deformation postulated in the theory of isostasy the theory of isostasy as conceived in this paper does not adequately account for the folding of rocks of the earths crust the theory of isostasy cannot account for the general uplift of sedi ments without folding. Take a quick interactive quiz on the concepts in isostasy. Diastrophism involves the movements of the earths tectonic plates. The study of diastrophism encompasses the varying responses of the crust to tectonic stresses. Diastrophism refers to deformation of the earths crust due to diastrophic movements deforming movements such as folding, faulting, warping bending or twisting of a large area and fracturing. Isostasy 1 modelling the state of balance of the earths outer layers isostasy is essentially the principle of hydrostatic equilibrium applied to the earth the oxford companion to the earth, 2000 otherwise called buoyancy. The theory of isostasy postulates that the earths crust is in a state of equilibrium and behaves as if it is floating on top of the mantle such that it rises when materials, e. Diastrophism is a process that results from the stress and strain of earths crust.
Isostasy 1 modelling the state of balance of the earth. All processes that move, elevate or build up portions of the earths crust come under diastrophism. Volcanismit results from volcanic action,the process of bringing molten rock from deepseated source. Many theories about what causes these movements include pressure via the. All process that move elevate or duild up portions of the erth. We look at an analogy and briefly discuss the concept of isostatic adjustments in the earths crust. Tectonism definition of tectonism by merriamwebster.
377 1358 1441 907 92 343 106 1226 1167 1083 608 1294 337 838 971 1010 1361 34 648 331 6 602 892 1114 1211 936 926 1453 1117 400 1201 1518 330 1334 506 370 1185 1170 263 1015 1288 457 404 119 1121 260