All rocks are in the earth's surface can serve as raw material for the formation of new sedimentary rocks.
follow a process of change, deposit and finally consolidated in a new rock.
this process is called weathering and distinguish between:
· physical weathering, involves the division of rocks into fragments as a result of changes in temperature by gelifracción.
· chemical weathering, involves the chemical alteration of the rock to make grain of sand.
.. .. Transport of materials
With a fan found that the wind transports fine particles. With a bent pipe transports water found that fragments of different sizes, depending on the speed of the current.
Ice is the only one that can carry large boulders that travel embedded in the ice mass. Sedimentation
.. ..
materials from weathering are transported for a while. But when the environment in which travelers lose the strength to continue carrying them, deposits, forming sediment.
sediments usually deposited in the sea or on the border between the continent and ocean. Continental
: is composed of sediments that have settled in places like a river, a lake, a glacier or have been transported by wind.
of transition, including beaches, deltas, lagoons and marshes.
Marinos, are the areas of the ocean in which it has formed a blanket of sediments from rivers, wind, etc. ..
Consolidation of sedimentary rock ..
the last process of sedimentary rock formation is the consolidation and diagenesis of the sediments were deposited.
This is done a few ways:
Cementation: Water that occupies pores of sediments that precipitate has dissolved substances, filling the pores and bonding materials as would the cement.
Compaction: the new layers of sediment placed on the already deposited, compressed so that the pore water is expelled, compacting sediments slowly in a rock.
Sedimentary rocks are formed from any rock that has undergone a process of weathering, transport, sedimentation and diagenesis.
.. magmas are igneous rocks ..
land
As the temperature increases and the rocks in these areas starts to melt to form magma.
· Volcanic - forms by the solidification of magma in the earth's surface.
· Pluto - is formed by the solidification of magma inside the earth, in large magma chambers.
· Philonian - are formed at a depth intermediate between the earlier solidified the map inside the cracks.
.. Where do igneous rocks? ..
volcanic rocks: are formed as a result of cooling and solidification of magma that reaches Earth's surface.
This cooling is fast and prevents the magma crystallized well. Plutonic rocks
(pluton, batholith) are formed at great depth, by solidification of magma chambers which can not escape. Rocks
Philonian (sill, dike, laccolith), are formed at shallow depths, by solificación of magma that has escaped through cracks but has not managed to reach the surface. The cooling of the magma has been faster than in the plutonic rocks, but slower than in the volcanics.
structure of the volcano .. ..
The volcanic rocks are formed by cooling and solidification of material from the eruption of a volcano. These eruptions can occur in two quite different ways, depending the volcano is effusive or explosive. Activity
effusive, basaltic lava is out at high temperatures, so it is not very viscous. The gases do not accumulate and go abroad, reducing the number and intensity of the blasts. Few pyroclastic form, because the lava is at high temperature.
explosive activity, lava is very viscous, solidifies and blocks the vent. The gases accumulate, increase pressure and cause strong explosions. Abundant pyroclastic originate. Can form low clouds amass everything found.
types of volcanic activity .. .. Activity
-effusive basaltic lava gases do not accumulate, are few piroclatos. Activity
explosively very viscous lava, gases accumulate, cause abundant piroclatos.
.. Rocks turn into other rocks ..
The high pressures and temperatures that exist in the Earth's interior not only lead to the formation of magmas.
All of these changes is called metamorphism and factors affecting it are:
- High temperatures, causing certain changes in rocks: water loss, modification.
-High pressure, causing the minerals that make up rocks in layers or bands have more or less horizontal and perpendicular to the direction pressure exerted.
.. Where are metamorphic rocks .. According
influence the pressure or temperature in a given area, distinguished three types of metamorphism: contact, regional dynamic.
Dynamic: dynamic metamorphism.
is caused by an increase in pressure without the temperature reaches high values.
Contact: contact metamorphism.
occurs simultaneous increase in pressure and temperature. Regional
: regional metamorphism.
occurs simultaneous increase in pressure and temperature.
.. The rock cycle ..
The rocks can be changed and transformed from a sediment, a fiery and even other metamorphic.
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