Basalt is solidified lava that was emitted at temperatures of more than 1,000 degrees.
It is easy to imagine the lava produced by a volcano as an incandescent liquid, but this isn’t the case.
When a volcano erupts, its products are always partly liquid, partly solid and partly gaseous.
The solid part often includes mineral crystals that form at temperatures even higher than that of the lava that has formed the basalt.
These crystals are formed at a depth of several tens of kilometres within the earth’s crust. Seen with a microscope, these crystals are clear and have bright colours. The liquid part appears to us as an aggregate of tiny crystals, which, in these images, surround the larger crystals. For scientists, these micro-crystals are very important, because they give us information from depths that cannot be explored directly.
|Type of rock:||
Effusive magmatic rock
Pyroxenes, olivine, plagioclase, magnetite. Calcite, serpentine and zeolites as alteration minerals
|Location:||Pannone (N 45° 53′ 12.4″ E 010° 55′ 00.3″)|
Basalt of the Val Lagarina
: Middle Ecocene (56-38 million years)
|Depositional environment:||aerial or submarine lavas, filling of superficial fractures.|