The liquid mass is in constant motion between continents, oceans and the atmosphere, forming the water cycle.
How it occurs
The evaporation of the liquid masses and the evapotranspiration of the vegetation transfer moisture to the atmosphere , which condenses, forms clouds and returns to the surface in the form of snow, rain, hail or fog.
Part of this water seeps into the soil and feeds the underground sheets, which, in turn, give rise to springs or water eyes, resuming the cycle again.
The water cycle occurs thanks to solar energy that allows the change of physical state . The water evaporates from the aquatic and terrestrial surfaces, forming clouds. It condenses and precipitates in the form of rain, snow or hail.
On the ground, water can cross the different horizons (layers) attracted by the forces of gravity, and reach the water table, from where it reaches a river or stream. Part of the precipitated water can be retained by the soil and absorbed by the plants, through its root system.
Stages of the Water Cycle
The water cycle can be divided into a short cycle (or short cycle) and a large cycle (or long cycle).
The water present in lakes, seas and also infiltrated in the soil evaporates and passes into the gaseous form.
In the upper layers of the atmosphere, the water vapor undergoes condensation and forms clouds that return to the Earth’s surface like rain. When the cooling of water vapor is excessive, hail or snow is formed.
The precipitated water in the form of rain, snow or hail infiltrates the soil again, forming groundwater, or drains over the surface, reaching rivers and oceans.
In this cycle, the participation of living beings occurs. The water absorbed by the plant’s roots, necessary for photosynthesis , is eliminated through transpiration and gutting into the atmosphere.
Animals obtain water through ingestion and food. Used in a series of vital metabolic processes, water is lost in part through breathing and excretion (urine and faeces), most of which is lost through perspiration, returning to the environment.
Importance of the water cycle
The most abundant component of living matter, water must necessarily be recycled to guarantee the life of the planet, the earth’s surface is covered with 75% water.
Of all this water that covers the land, about 97% belongs to marine ecosystems. Of the remainder, only 1% is available on the surface (52% in lakes, 38% retained in the soil, 8% in the atmosphere, 1% in living organisms and 1% in rivers).
The Cycle of Rocks begins with the destruction of rocks on the surface by the action of external agents, such as weathering and erosion or the agglutination of both.
Weathering is the process of degradation of rocks, it happens when exposed to the atmosphere they suffer an erosive attack, caused by the climate, which can modify their physical aspect or their mineralogical composition. Erosion is the process of mechanical wear, operated by running water, the wind, the movement of glaciers and the seas.
The products resulting from the destruction are transported by various fluids, starting to circulate on the Earth’s surface due to the action of solar heat and gravity.
When the energy that makes them circulate ceases, they are deposited in the lower regions, then forming sedimentary rocks .
Over time, sedimentary rocks are buried at great depths, consequently suffering the effect of terrestrial heat and becoming harder and harder.
At the deepest levels, about 10 to 30 km, the temperature and pressure are higher, with the transformation into metamorphic rocks .
The temperature keeps increasing more and more, the fusion occurs and it turns into igneous rock .
Due to the action of the mantle movement, this igneous rock is lifted, more and more, it tends to rise to higher levels.
After millions of years, the rock finally reaches the earth’s surface and again begins to suffer the action of external agents, thus restarting the cycle.
- Weather attack, erosion and transport.
- Cementation, diagenesis (transformation of incoherent sediments into consolidated sediments), recrystallization at low temperature.
- Fusion by direct incorporation into any igneous mass after subsidence.
- Metamorphism: by the increase in temperature conditions, guided pressure or by the combination of both processes, thanks to subsidence (slow descent).
- Volcanism: through crust ruptures, the basaltic magma from the mantle spills to the surface.
- Uplift combined with erosion of the upper layers.
- Formation of gabbros (plutonic magmatic rock, usually black), peridotites (granular eruptive rock), kimberlites (brecciated volcanic magmatic rock – is the diamond matrix rock and occurs in the form of chimneys or dikes), etc.
- Formation of metabasites.