Ch 3 Rocks Unit 2 Igneous Rocks

Explanation
Erosion refers to the process of weathering and removing rock through various natural agents such as air, water, or glaciers. These agents gradually break down and carry away the rock particles, causing the landscape to change over time. Erosion can occur through processes like wind erosion, water erosion, or glacial erosion, depending on the dominant agent involved.

Explanation
Pumice is the correct answer because it is the only option that is mentioned twice in the given list of materials. The repetition of "Pumice" suggests that it is the correct answer.

Explanation
Obsidian is a type of volcanic glass that is formed when lava cools quickly and solidifies without crystallizing. It has a smooth and glassy texture and is usually black or dark in color. Pumice, on the other hand, is a type of volcanic rock that is formed from frothy lava with trapped gas bubbles. It is light in weight and has a porous and rough texture. Basalt is a common type of volcanic rock that is formed from solidified lava. It is usually dark in color and has a dense and fine-grained texture. Based on the given options, Obsidian is the correct answer as it is the only one that matches the description of a volcanic glass.

Explanation
Granite is the correct answer because it is the only word that appears twice in the list. The other two words, lignite and pumice, only appear once each.

Explanation
Basalt is the correct answer because it is the only option that is a type of rock. Diamond is a precious stone, and anthracite coal is a type of coal. Basalt, on the other hand, is a type of volcanic rock that is commonly found in igneous formations.

Explanation
The correct answer is "Intrusive." This term refers to rocks that form below the Earth's surface through the process of solidification of magma. These rocks cool slowly, allowing for the formation of large crystals. Examples of intrusive rocks include granite and diorite.

Explanation
A laccolith is a type of igneous intrusion where magma is injected into the earth's crust and forms a mushroom-shaped body. It is formed when slow-moving magma pushes up the overlying rocks, creating a dome-like structure. This process occurs underground, and the magma does not reach the surface, hence it is classified as an intrusive rock formation. Therefore, the given description of a rock body made from slow-moving magma and forming a mushroom shape aligns with the characteristics of a laccolith.

Explanation
Extrusive rocks are formed from lava that cools and solidifies on the earth's surface. This process typically occurs in volcanic eruptions, where molten rock is ejected onto the surface and rapidly cools, resulting in fine-grained or glassy textures. Examples of extrusive rocks include basalt and obsidian. In contrast, intrusive rocks are formed from magma that solidifies beneath the earth's surface, resulting in coarse-grained textures. Dikes and batholiths are specific types of intrusive rocks.

Explanation
An erosion is a process in which the earth is worn away. It involves the gradual removal of soil, rock, or sediment from the Earth's surface by natural forces such as wind, water, or ice. Additionally, erosion can also contribute to the creation of rocks over time through the deposition and compaction of eroded materials. Therefore, the correct answer is both.