Final answer:
Rhyolite, an igneous rock, is formed from cooling lava and has a fine texture. It is different from sedimentary rocks, which are cemented particles, and metamorphic rocks, which are transformed under heat and pressure. Rhyolite's cross-cutting nature indicates that it is younger than the rocks it intrudes, which helps in interpreting Earth's history.
Step-by-step explanation:
The investigation of the different rock types and their formation is a key component of understanding Earth's geology. In this context, rhyolite is mentioned, which is a type of igneous rock. Igneous rocks, including rhyolite, form from the cooling and solidifying of magma or lava. Rhyolite has a similar composition to granite but with a finer texture due to the rapid cooling of lava which prevents large crystals from forming.
Sedimentary rocks are formed from particles that have been weathered from pre-existing rocks and are then cemented together. On the other hand, metamorphic rocks originate from the transformation of existing igneous or sedimentary rocks under extreme heat and pressure that cause physical and chemical changes without melting the rock.
Given that rhyolite is described as cross-cutting and covering all units except sandstone, it suggests that it is younger than the other rock units it intrudes, based on the principle of cross-cutting relationships used in geologic studies.