Answer:
Formation 2 is an intrusion
Formation 1 is an extrusion
Formations 1 and 2 are igneous rocks
Explanation:
The rocks that form from the cooling off of magma deep into the crust, or from the lava flows on the surface, fall into the category of igneous rocks. These rocks are the toughest rocks, and they are the ones that give the basis for the further formation of the metamorphic and sedimentary rocks if particular conditions are on display.
The igneous rocks are divided into two major groups:
- intrusive; the intrusive igneous rocks form deep into the crust from the magma that cooled off. Because they are exposed to higher temperatures and pressure, the magma cools off slowly, so the crystals are larger.
- extrusive; the extrusive igneous rocks form on the surface from the cooling off of the lava. Because the cooling off happens on the surface, where the temperatures and pressure are much lower, it is very quick. This results in these rocks having very small crystals, as they do not have enough time to grow further.
