In the process of release of magma from the bowels of the earth to the surface of the earth there are two kinds of processes, namely the magma intrusion process and the magma extrusion process. Where in the process of magma intrusion will produce some forms such as batolit, lakolit, still, alley, apolisa and diatrema. If in the previous discussion we have discussed about the notion of lakolit then in this discussion we will discuss about batolit.

Understanding Batolit is one of the igneous rocks formed in the magma kitchen that is formed due to a decrease in temperature that slows down. Batolith is a form of intrusion that has no foundation that can usually be found in the core of the mountains. The top or roof of the batolit is usually known from the remnants of sedimentary rock that will hang, which is called roofpendants.

Batolith and Mountains
What is meant here is the relationship of batolith with the formation of mountains, where the formation of this batolit usually along with the formation of a mountain. The upper part of an irregularly shaped dome-shaped batolit and a side wall of steep rock. The mass of the rock has a wide spread downward and sideways, but the bottom is never visible and also the arrangement of these rocks is usually granite or granodiorite. There is a batolit that has a very large size, for example is a batolit located in Alaska British Columbia which has a length of about 1250 miles and width of about 50 miles.

In Indonesia alone there is a known batolit in the Schwaner mountain range in Borneo. The process of formation of this batolit is not known for certain but there is an old opinion that says batolit is formed due to filling of the empty space in the earth's crust. The vacancy in the earth's crust is caused by the process of folds and faults.

Generally, batolit moves to follow the weak plane of the earth's crust but what remains to be asked is whether the mass of the rock makes space in the earth's crust by destroying rocks or by pushing the rock around it sideways and upwards.

1. The relationship with the Mountains
Hinking batolith with the mountains is based on the opinions of experts and also how the process is formed, the following explanation:

- Expert opinion
Some scholars believe that magma will seek its way upward by melting the rock through which the magma path passes. This process will cause the magma will change the arrangement and will produce rocks of different types. In reality, however, most of the batolites exhibit almost identical arrangements of rocks.

Thus, the same mass of batolith does not fit the theory of assimination. There is another theory which explains that the occurrence of batolite is by magmatic stoping, ie the rocks found at the top of the batolith will break apart due to heat expansion and then the cracking of these rocks will be separated from one another by impregnation of gases and magma fluid entering the crack in the crust earth.

- Process Formation
The chunk will eventually sink into the magma. There is a notion that this process can be seen on the edge of the batolit body which usually has an irregular shape and is present in foreign rocks or xenotites on the top of the batolith. If the chunks deepen then the foreign rock will be reduced and gradually will not be found again. However, this process has little peculiarity as if the magma that is usually granite upward, then the magma will penetrate reach the surface of the earth and then will form a volcano that will produce rhyolite or glass rock.

In this case the rhyolite rocks are supposed to be large amounts of igneous rocks (igneous rocks). However, based on the investigation of leleran rocks, most of these rocks have a basal arrangement although there are inner rocks that are mostly made up of granite rocks. Generally, sedimentary rocks located around the batolit will not show symptoms of dislocation, which is a symptom of change from the horizontal position of the sedimentary rock.

2. Opinion on the Origin
Most experts consider that essentially the original rocks discussed above are still present in the former and they can turn into rocks resembling granite rocks, this can happen because the side rocks are penetrated by gases and minerals so as to alter their rock formations and are affected by the addition and subtraction of existing materials so that granite rocks are formed. There is also an assumption that the occurrence of granite rocks in bakolites is caused by the exchange of atoms between atoms in a solid state.

That is why batolit has a relationship with the formation of mountains where this batolit will form a mountain based on magma activity and also the compaction process.

Example Batolit
In addition to large batolit located in Alaska British Colombia which has a length of about 1250 miles and width of about 50 miles and also batolit in Indonesia known in the Schwaner mountain range in Borneo. There is also an example of a famous form of batolite in the western part of North America is a giant batolit outcrop called Half Dome formed in Sierra Nevada, United States where batolit has a composition of granite rock.

The occurrence of these giant batolit outcrops is influenced by the pressure of the tectonic plates. Batolit that is exposed to the surface of the earth from within the bowels of the earth is influenced by the two forces to change the shape of the face of the earth that is endogenous and exogenous. Exogenous energy is the earth-shifting force that comes from outside the earth, for example, weathering, erosion, sedimentation and masswating. Endogenous energy is a form of earth-shifting force that comes from within the earth, for example, is volcanism, tectonism and earthquakes.

Batolites exposed due to endogenous forces are formed due to the effect of erosion. Where the initial process of batolite that is covered by weathered rock material will experience erosion in the upper layer which will over time reveal the batolit. Then on batolit exposed because exogenous power is influenced by the process of appointment in the area. The lifting of the batolith is influenced by the pressure of the tectonic plates moving underneath. Keep in mind that the formation of batolit in America is composed of various plutons that formed during the last 150 million years.

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