Rocks and Minerals Quiz

Rocks and Minerals

• Minerals are naturally occurring, solid substances with a specific chemical composition and high-ordered atomic structure. They have a specific physical property and form crystal solids with three-dimensional plane faces.

Mineral Properties

• Color: Least reliable for identification.
• Streak: The color of a mineral in powdered form. Halite and quartz are difficult to distinguish based on color, luster, and streak.
• Hardness: Resistance to scratching. The Mohs Hardness Scale lists minerals from hardest to softest.
• Cleavage/Fracture: The way a mineral breaks. Cleavage shows smooth, planar surfaces, and fracture is a more or less random pattern without planar surfaces. Examples include Galena and Halite (fracture) and Quartz (conchoidal fracture).

Mohs Hardness Scale

• The scale ranks minerals from 1 (softest, talc) to 10 (hardest, diamond).
• Common objects are used for comparison (e.g., fingernail = 2.5, copper penny = 3).

Other Mineral Properties

• Crystalline structure: The geometric shape of mineral crystals.
• Transparency/diaphaneity: How well light passes through a mineral.
• Magnetism: Minerals that attract iron.
• Tenacity: Resistance to breaking (example: Mica is flexible).
• Luster: How a mineral's surface reflects light.
• Odor: Some minerals have unique smells.
• Specific Gravity/Density: The weight of a mineral compared to an equal volume of water.

Rocks

• Rocks are aggregations of minerals and rock fragments.
• Igneous rocks: Formed from cooling and solidifying of molten rock (magma or lava).
• Sedimentary rocks: Formed from the remains of once-living organisms (e.g., fossils) or sediments.
• Metamorphic rocks: Formed by heat and pressure changing existing rocks.

Rock Cycle

• A cycle that describes the transitions between the three types of rocks (igneous, sedimentary, and metamorphic).

Endogenic Processes

• Processes that occur beneath the Earth's surface (driven by heat and gravity).

Exogenic Processes

• Processes that occur on the Earth's surface (e.g., weathering, erosion, deposition).

Important Earth Surface Processes

• Faulting: Displacement of rock along a fracture.

• Solifluction: Slow downslope movement of soil.

• Weathering: Physical and chemical breakdown of rocks.

• Mudflows: Rapid flow of saturated earth materials.

• Mass wasting: Downslope movement of rock and soil.

• Debris flows: Type of mass wasting involving sediments.

• Erosion: Wearing away of the Earth's surface by wind, water, or ice.

• Deposition: Dropping of sediments in a new location.

• Denudation: Removing layers of the Earth's surface.

• Earthquake scales: Mercalli and Richter scales measure earthquake intensity and magnitude, respectively.

• Volcanic Landforms: Shield volcano, caldera, etc.