Question

student exploration: rock classification
vocabulary: classify, extrusive igneous rock, foliation, fossil, igneous rock, intrusive igneous rock, metamorphic rock, mineral, sedimentary rock, strata, texture, vesicle
prior knowledge questions (do these before using the gizmo.)
when you classify objects, you organize them into groups based on common characteristics.

1. what are some different ways you could classify these marbles?
2. what characteristics do you think scientists use to classify rocks?

gizmo warm - up
rocks are classified by how they formed. the three types are:

• igneous rocks form from cooling magma or lava.
• sedimentary rocks form from the bonding of rock fragments such as sand, silt, or clay; from organic materials; and from chemicals dissolved in water.
• metamorphic rocks form when other rocks are changed by heat and pressure.

in the rock classification gizmo, you will get to explore these three types of rocks. think about how each type of rock is formed.

1. fossils are the remains of ancient plants and animals. which type of rock do you think is most likely to contain fossils?
2. foliation occurs when minerals are flattened by heat and pressure. this results in a layered or banded texture. which type of rock do you think is foliated?
3. air pockets, or vesicles, can form in rapidly cooling magma or lava. in which type of rock would you expect air pockets?

Explanation:

1. Sedimentary rocks often contain fossils because they form from the accumulation of sediments, which can include the remains of ancient plants and animals.
2. Metamorphic rocks are foliated. Foliation occurs due to the alignment of minerals under heat and pressure during metamorphism.
3. Extrusive igneous rocks (a type of igneous rock) would have air pockets (vesicles). When magma or lava cools rapidly, gases trapped in it escape, leaving behind these pockets.

Answer:

1. Sedimentary rock
2. Metamorphic rock
3. Extrusive igneous rock