Full Definition of PRECEDING. See preceding defined for English-language learners. See preceding defined for kids. ADVERTISEMENT. I have had a fever of about three weeks during the last and preceding month, from which I am entirely recovered except as to strength. â 2 Thomas Jefferson, letter, 4 Sept. 1823.
This commonly happens along volcanoes. When lava comes out of the volcano, the rocks there melt, usually forming different rocks. If you are asking on the chemical basis as to why they melt, it's because rocks are formed from minerals crystals. These crystals are formed from elements, which in turn also melts (some rocks are made of carbon, and since carbon melts, rock melts too). Source(s): Gsevilla Â· 7 years ago.
Igneous rocks are formed by the cooling and crystallization (solidification) of magma. 1. Magma. Magma is a complex, highly variable mixture of molten rock, dissolved gas and solid crystals.s a magma begins cooling inside the earth, high-temperature minerals are the first to form crystals. These solid crystals float within the remaining molten rock. This partially crystallized / partially molten magma is then extruded, so that it cools very rapidly.