وصف علمي لظاهرة البراكين. بحث كامل عن البراكين بالافكار 2020

Felsic lavas or tend to be highly not very fluid and are erupted as domes or short, stubby flows	When the icecap melts, the lavas on the top collapse leaving a flat-topped mountain
Water released from the subducting plate lowers the melting temperature of the overlying mantle wedge, creating	Very good examples of this type of volcano can be seen in Iceland, however, there are also tuyas in

البركان

Cinder cones may form as flank vents on larger volcanoes, or occur on their own.

لماذا تحدث البراكين ؟ وما آثارها وفوائدها ؟: Finally, explosive volcanic eruptions release the greenhouse gas carbon dioxide and thus provide a deep source of for biogeochemical cycles
لماذا تحدث البراكين ؟ وما آثارها وفوائدها ؟: A large number of minor and trace gases are also found in volcanic emissions, for example , , , organic compounds, and volatile metal chlorides
البركان: These so-called "" , for example at , can occur far from plate boundaries

The concentrations of different can vary considerably from one volcano to the next	Typical examples for this kind of volcano are and the volcanoes in the
Then, the pillow lavas also collapse, giving an angle of 37	This magma tends to be very due to its high content, so often does not reach the surface and cools at depth

البراكين

The release of pressure due to the thinning of the crust leads to expansion, and the partial melting of the causing volcanism and creating new oceanic crust.

بركان: Most are at the bottom of the oceans, therefore most volcanic activity is submarine, forming new seafloor
البركان: 's , formed by the eruption of near in 1912, is an example of a thick or deposit
لماذا تحدث البراكين ؟ وما آثارها وفوائدها ؟: These can be relatively short-lived eruptions that produce a cone-shaped hill perhaps 30 to 400 meters high