Question

2. Give an example of how a rock would not go completely through the rock cycle.

3.
What unique factor about the arrangement of mineral crystals occurs in many
metamorphic rocks?
4. What procedure would you follow to determine the name of a specific igneous rock?
5. Describe the differences between detrital and chemical sedimentary rocks.
What type of rock is most likely to contain fossils, and why?

Answer 1

The rock cycle involves transformations of rocks into different types, but a rock may not complete this cycle. Igneous rocks are classified by their texture and mineralogy, while metamorphic rocks often exhibit foliation. Sedimentary rocks are most likely to contain fossils.

Step-by-step explanation:

The rock cycle consists of the processes that transform rocks from one type to another over geologic time. An example of a rock not completely going through the rock cycle is a sedimentary rock being uplifted and undergoing erosion before it can be buried and metamorphosed. Metamorphic rocks often exhibit a unique foliation pattern due to the realignment of crystals under heat and pressure.

To determine the name of an igneous rock, examine its texture and composition, identify the minerals present, and then classify it based on whether it is intrusive or extrusive and its mineral composition. Detrital sedimentary rocks are made of clasts of pre-existing rocks, while chemical sedimentary rocks form from mineral precipitation. Sedimentary rocks, particularly those that are detrital like sandstones and shales, are most likely to contain fossils due to the accumulation and preservation of organic material in sedimentary environments.

Answer 2

The rock cycle involves the transformation of igneous, sedimentary, and metamorphic rocks. Igneous rocks form from cooled magma or lava, sedimentary rocks from cemented fragments or precipitates, and metamorphic rocks from the alteration of existing rocks under pressure and temperature. Detrital sedimentary rocks are most likely to contain fossils.

Step-by-step explanation:

The Rock Cycle and Rock Types

Igneous rocks form from the cooling and solidification of magma or lava. The minerals start to crystallize as the magma cools, interlocking in random orientations. Sedimentary rocks form from the cementation of weathered pieces of other rocks, or from minerals precipitating out of solution. Metamorphic rocks, which have undergone physical or chemical changes due to high temperature or pressure, often show a pattern or orientation in their minerals known as foliation.

Unique Factors in Metamorphic Rocks

Metamorphic rocks exhibit foliation, which is a unique arrangement of mineral crystals resulting from directed pressure and high temperature. This process doesn't always melt the rock, therefore enabling solid-state recrystallization.

Identifying Igneous Rocks

To determine the name of a specific igneous rock, one must examine its mineral composition, texture, and formation environment. The tectonic setting can provide insights into the processes contributing to rock formation.

Differences in Sedimentary Rocks

Detrital sedimentary rocks are made up of solid particles from weathering, while chemical sedimentary rocks form from chemical precipitation. Fossils are most likely to be found in detrital sedimentary rocks, as these rocks often form in environments where organisms lived and were buried.