Contoh Explanation Text About Volcano Terbaru – Apakah kalian masih ingat apa yang dimaksud dengan Explanation Text? Yup, Explanation text merupakan salah satu jenis teks dalam Bahasa Inggris yang digunakan untuk memberikan penjelasan mengenai proses bagaimana suatu fenomena dapat terbentuk. Volcano atau gunung berapi merupakan salah satu peristiwa alam yang dapat dijelaskan prosesnya melalui Explanation Text. Berikut adalah contoh Explanation Text mengenai Volcano.
Volcano is a place where rocks or holes and incandescent or gas, usually both, come out to the surface of the earth, and the solid material that accumulates around the hole forms a hill or mountain (Macdonald, 1972). Thus the emphasis is on the understanding of volcanoes and discharge hole magma, while the form of a landscape of hills or mountains is not a necessity, since many volcanoes are not forming a mountain. Volcanic eruption itself implies as an event that occurs due to deposition of magma in the earth that is pushed out by the high-pressure gas.
Volcano may erupt as a result of increased mobility bouyancy and magma body. This happens under, in, and above the magma chamber. Magma chamber is driven by rock resulting magma volume increases and is eventually emerged as the eruption. Knowledge of plate tectonics is the beginning of solving the puzzle of natural phenomena including mountain ranges, continental, earthquakes, and volcanoes. Earth has a lot of fluids and water on the surface. Both these factors greatly influence the formation and composition of the magma and the locations and volcanic events.
The heat inside the earth is hot formed during the formation of the Earth about 4.5 billion years ago, along with the heat arising from natural radioactive elements, such as elements of the isotope K, U and Th with respect to time. Formed by the earth during hot temperature, but then cooled gradually in accordance with its historical development. The cooling occurs due to the release of heat and intensity vulcanisme on the surface. Propagation of heat from the earth to the surface is in the form of convection, where the materials are heated on the base coat, the depths of 2,900 km below the earth, moves and narrowed spreads around. In the upper mantle, about 7-35 km below the earth, these materials cools and becomes solid, then sinks again into the convection flow.
Lithosphere includes the crust, generally has a thickness of 70-120 km and split into several large fragments called tectonic plates. Plates move each other and also penetrate into the mantle convection. Litosphere moves pedestal above the zone of weak upper mantle, which is also called astenosfir. Astenosphere weaker section occurs at or near the temperature at which melting starts to happen, as the result some parts of astenosphere melt, although most are solid. Continental crust has lk.35 km thick, low-density and age of 1-2 billion years, while the oceanic crust is thinner (lk. 7 km), is more dense and is not older than 200 million years. Continental crust position is on top of the oceanic crust due to differences in specific gravity, and both floats on astenosphere.
Volcanic eruptions can cause various effects or results. Impact of volcanic eruptions can influence directly or indirectly and nature can be destructive (negative) or a blessing (positive) to the surrounding community. The negative impact / danger of volcanic eruptions are as follows:
Pyroclastic fallout: Pyroclastic fallout eruptions are occurred from forming columns of smoke high enough, when the energy runs out, the ashes will be spread in the direction of the wind and then fall back to earth. Ashfall is not a direct danger to humans, but the ash deposition will shed leaves and small trees so damaging and at a certain thickness it can knock down the roof of the house. Distribution of ash in the air can darken the earth while threatening danger to the flight path.
Pyroclastic flows (hot clouds): Pyroclastic flows can occur due to the collapse of Plinian eruption columns of smoke, eruption directly to one direction, glowing lava dome or lava tongue and flow at ground level (surge). Pyroclastic flow is largely controlled by gravity and tend to flow through low areas or valleys. High mobility pyroclastic flow is influenced by the release of gases from magma or lava or from the air heated during flowing. The flow velocity can reach 150-250 km / h and a range of flow can reach tens of kilometers although moving on the water / sea.
Lava flow: Lava flow is a concentrated liquid lava and its heat can destroy everything in its path. Its speed depends on the viscosity of lava flows. The lower the viscosity is, the more far-reaching stream is. Temperature erupted lava at the time is ranged from 800-1200 C. In general in Indonesia, the flow of lava which erupted volcanoes, has intermediate magma composition, so the movement is quite slow, so that people may go away from it.
In addition to the negative impacts above, volcanic eruptions also have a positive impact even if only for residents in the surrounding areas, such as; Lands affected by the result of volcanic volcano is very good for agriculture because the soil naturally becomes more fertile and can produce plants that are much more qualified, material volcanic, such as sand and stone have economic value that can be an alternative to a new livelihood to the locals as sand miners and stone. Although forest ecosystems is damaged, but in some time it will grow more trees that form a new forest ecosystem. After the mountain erupted, geysers or hot springs are coming out of the earth with a regular or periodic basis and contain certain minerals that are good for skin health.
Demikianlah contoh Explanation Text mengenai gunung berapi atau Volcano. Semoga contoh teks tersebut dapat bermanfaat dan membantu kalian semua dalam memahami Explanation Text lebih baik lagi. Terima kasih.