When we talk about rock cycle Or sedimentary cycles refer to the set of stages through which some mineral elements and rocks evolve during their stay in the Earth's crust. All phases of the cycle involve a sequence of transformations that shape and change the composition. Ultimately, various transformations are generated in a circular time series that repeats itself over long periods.
In this article we are going to tell you everything you need to know about the rock cycle and its importance.
What is the rock cycle
We must keep in mind that this is a biogeochemical cycle in which the storage of a specific element occurs in the Earth's crust. All the mineral elements present are objects of the rock cycle, also known as sedimentary cycles. For example, we have some mineral elements such as They are sulfur, potassium, phosphorus, calcium and other heavy metals.
The rock cycle begins with an exposure of rocks to these elements from deep within the crust. They can also be found in areas close to the surface. After they are exposed, they are subjected to weathering processes, for which they also suffer erosion by external agents. Among these external agents we have the atmospheric, hydrological and biological factors.
All material that erodes over time is transported by water, gravity, or wind. Once the material has been transported, it will remain in one place to undergo the sedimentation process. Sedimentation is nothing more than a process where a deposition of mineral material takes place on the substrate. Sediment layers accumulate over thousands of years, so we have to bear in mind that this is measured on a scale of geological time. Throughout these millions of years they undergo complex compaction and cementing processes.
This is how sediments are formed through lithification, which is how they are transformed into solid rock. This process takes place at great depths. Furthermore, within the rock cycle, there are intermediate phases that also occur due to biological processes. This biological phase includes solubilization and absorption by living organisms. Depending on the type of mineral, its composition and substances, along with the environmental conditions, can be absorbed by plants, bacteria or animals and pass into trophic webs. Once the minerals have been absorbed they are again excreted or released by the death of the organism. This is how the cycle closes.
Key features
Let's analyze the main characteristics of the rock cycle. We know that it constitutes one of the three types of biogeochemical cycles, and its main characteristic is the isolation matrix in the lithosphere. These cycles have their own discipline of study called sedimentology. Sedimentology It is the science that is responsible for studying the rock cycle and the importance it has in the geology of the terrain.
The length of the cycle is characterized by the time it takes to complete different stages. This time is often too long to measure on a human scale. It must be measured in millions of years because minerals remain embedded in rocks for long periods of time. These rocks are usually located deep within the Earth's crust. The pressure exerted by gravity and other materials is one of the main drivers that triggers the beginning of the rock cycle.
Stages of the rock cycle
Let's look at the different stages of the rock cycle. It's important to remember that this isn't a cyclone whose stages always follow a written sequence. Since they're normally influenced by different variables and factors, the phases can occur or alternate several times during the process.
Exposure phase
It is the phase where rocks formed at certain depths in the Earth's crust are subjected to diastrophic processes. These processes are summarized in various fractures, folds, and elevations of the ground. These ground movements are mainly due to the Tectonic plates and their movement. In this way, the rocks were exposed to the action of various environmental factors, whether edaphic, atmospheric, hydrological, or biological.
Diastrophism is nothing more than the product of the movements that exist between the convection currents of the earth's mantle. These movements are also generated by volcanic phenomena that expose the rocks in a more intense way.
Weathering phase
In the weathering phase exposed rocks undergo decomposition into smaller fragments, This being physical weathering, or changes in its mineralogical composition, this being chemical weathering. It is a key factor in soil formation and can be not only physical or chemical, but also biological.
Erosion phase
In this phase, we see the direct action of wind and rain on the rock. These are products of weathering, which also includes the soil formed. The erosion phase also involves the transport of previously eroded material. It is attacked by erosive agents such as wind and rain.
Transport phase
The mineral particles are transported by these agents, be it water, wind or gravity itself. They are transported long distances, although depending on the size they have a defined load capacity.
Sedimentation and accumulation phase
It consists of the deposition of the transported material due to a decrease in the speed of the means of transport and the effect of gravity. It may be a fluvial, tidal or seismic sedimentation.
Rock cycle: solubilization, absorption and biological release
Once all the rock material has weathered, the released minerals can also dissolve. These minerals can also be absorbed by living organisms. Plants are consumed by herbivores, and these are consumed by carnivores. Ultimately, it is the decomposers that pass the minerals into the food web.
The last part of the rock cycle is lithification. They are divided into compaction and cementation. Lithification is simply the formation of a new rock. It occurs when minerals settle, forming successive layers that accumulate and exert enormous pressure. During compaction, the pressure exerted by the sediment layer increases in successive phases.
Finally, during the cementation phase, cementing substances are deposited between particles. These cementing particles are typically calcite, silica, oxides, and others, which are responsible for crystallizing and cementing the material. Thus, solid rock is generated.
I hope that with this information you can learn more about the rock cycle.