| Sediments and strata |
 The result of internal activity modifies the surface of planet Earth. These are called "internal geological agents. The new crust soon get the "attack" from other agents, external, which erode. Erosion produces waste rock material of various sizes which, over time, become fragmented into smaller pieces. The severity and transport by the action of wind or water deposited and accumulates in lower areas of land relief. This leads to the emergence of sediments deposited in layers, which are called "strata". Later, the lower layers, which support more weight, are transformed into new rocks, sedimentary rocks. Formation of sedimentary strata and The planet's surface is broken due to erosion, in smaller or larger pieces from blocks of rock to the fine silt through all Tamanoe loa of gravel and sand. The force of gravity and the drag of the water tend to deposit these fragments in the lower areas where, at times, accumulate huge amounts. These materials are formed successive layers called "strata". The type of layer depends on the weather and erosion that occurs in every age. This makes its study interesting to know the conditions of the past. The branch of geology that studies sediments and strata is called stratigraphy. The surface layers of sedimentary areas tend to be soft consstencia often ideal for agriculture. But over time, as new layers accumulate, the less they have to bear more weight and the particles, under increased pressure, are compacted. This, together with increased temperature, causing chemical changes that eventually become hard-rock sediment.
Only registered users can write comments!
Powered by !JoomlaComment 3.20
3.20 Copyright (C) 2007 Alain Georgette / Copyright (C) 2006 Frantisek Hliva. All rights reserved." |
|||||