magma
Definition
Magma is a molten or semi-molten rock that is found beneath the surface of the Earth. It is made up of liquid rock, dissolved gases, and suspended crystals. Magma is formed when rocks deep inside the Earth are heated up. The heat causes the rocks to melt, and the dissolved gases and suspended crystals are released. Magma can also be formed when two different types of rock collide.
The temperature of magma can vary depending on its location and composition. Magma that is found near the surface of the Earth is typically cooler than magma that is found deep underground. Magma that is formed from the collision of two different types of rock is typically hotter than magma that is formed from the melting of rocks.
Magma is important for the formation of igneous rocks. When magma cools and solidifies, it forms igneous rocks. Igneous rocks make up about 95% of the Earth's crust. Magma is also important for the formation of volcanoes. When magma erupts onto the surface of the Earth, it can create new volcanoes.
Magma is a fascinating and important part of the Earth's geology. It is responsible for the formation of igneous rocks and volcanoes, and it plays a role in the Earth's dynamic climate.
How can the word be used?
Magma can erupt from volcanoes, forming lava flows.
Different forms of the word
Noun: magma.
Adjective: magmatic.
Verb: to magmatize.
Etymology
The word "magma" comes from the Latin word "magma", which means "thick mass". It was first used in English in the 17th century.
The Latin word "magma" is thought to be derived from the Greek word "μάζα", which also means "thick mass". The Greek word "μάζα" is related to the verb "μάσσειν", which means "to knead". This is a reference to the way that magma is constantly moving and changing, like dough being kneaded.
Question
How is magma created?
AQA Science Exam Question and Answer
Question:
What is magma and how does it relate to the formation of igneous rocks? Describe the two main types of igneous rocks that can form from magma.
Answer:
Magma is a molten mixture of rock-forming substances, gases, and mineral crystals that exists beneath the Earth's surface. It forms from the melting of pre-existing rocks due to the intense heat and pressure within the Earth's mantle. Magma is the precursor to igneous rocks, which are formed when it cools and solidifies.
When magma reaches the Earth's surface through volcanic activity, it is called lava. As magma or lava cools, mineral crystals begin to form. The rate of cooling and the mineral composition of the magma/lava determines the texture of the resulting igneous rock.
There are two main types of igneous rocks that can form from magma:
- Intrusive Igneous Rocks: These rocks form when magma cools and solidifies slowly beneath the Earth's surface. The slow cooling allows larger mineral crystals to form, resulting in a coarse-grained texture. Examples of intrusive igneous rocks include granite and diorite.
- Extrusive Igneous Rocks: These rocks form when lava cools and solidifies quickly on the Earth's surface. The rapid cooling prevents large mineral crystals from forming, resulting in a fine-grained or even glassy texture. Examples of extrusive igneous rocks include basalt and pumice.