Lava is pouring out of the crust at a vent on the ocean floor. As it cools, igneous rocks form.

Question

Which characteristics would one expect to find when studying the cooled lava?

small crystals and coarse texture
small crystals and fine texture
large crystals and coarse texture
large crystals and fine texture

Answer 1

When lava cools rapidly, such as when it erupts on the ocean floor, it typically forms igneous rocks with small crystals and a fine texture. This rapid cooling does not allow larger crystals to form. Therefore, the correct characteristics you would expect to find when studying the cooled lava would be:

small crystals and fine texture.