Geology Exam 2 Flashcards
Why are some volcanoes explosive and others quiet?
A) The shape of the volcano
B) The thickness of the magma and gas content
C) The number of previous eruptions
D) The presence of water underground
B) The thickness of the magma and gas content
How do composition, temperature, and dissolved gases affect the viscosity of the magma?
A) Higher silica content, lower temperature, and more gases make magma thicker, and more explosive.
B) Lower silica content and higher temperature make magma more viscous
C) Dissolved gases decrease viscosity
D) VIscosity is not affected by these factors
A) Higher silica content, lower temperature, and more gases make magma thicker, and more explosive.
What are the materials produced by a volcano eruption?
A) only lava
B) ash, gases, lava, pumice, and pyroclastic materials
C) Only rocks and steam
D) Only gases and water
B) ash, gases, lava, pumice, and pyroclastic materials
What is a caldera
A) A volcanic crater formed after a massive eruption and collapse
B) A hardened lava flow on a mountain
C) A gas-filled chamber inside a volcano
D) A type of lava dome
A) A volcanic crater formed after a massive eruption and collapse
What is pyroclastic flow?
A) A slow-moving lava flow
B) a cloud of hot gas, ash, and rock that moves quickly down a volcano
C) A pool of magma inside a crater
D) a crack In the earth’s surface that releases steam
B) a cloud of hot gas, ash, and rock that moves quickly down a volcano
What is a lava dome?
A) A type of large crater formed by an explosion
B) a mound-shapes structure formed by thick, slow-moving lava piling up near the vent
C) A large piece of magma that cools inside a volcano
D) A type of underwater volcanic mountain
B) a mound-shapes structure formed by thick, slow-moving lava piling up near the vent
What is a fissure eruption?
A) An eruption that occurs through long cracks in the ground
B) A lava fountain that erupts only from a volcanic cone
C) a gas explosion from inside the volcano
D) A crater collapse forming a lake
A) An eruption that occurs through long cracks in the ground
What is a volcano neck?
A) A hardened lava plug left behind after the rest of the volcano erodes
B) A long lava flow that connects two volcanos
C) A crater filled with water
D) A crack in the earth’s surface where magma flows out
A) A hardened lava plug left behind after the rest of the volcano erodes
What role does weathering play in the rock cycle?
A) It turns sedimentary rocks into igneous rocks
B) IT creates magma directly
C) it breaks down rocks into sediment, which later forms new rocks
D) It only happens in deserts
C) it breaks down rocks into sediment, which later forms new rocks
What is mechanical weathering?
A) The breakdown of rocks through chemical reactions
B) The process of turning rocks into soil
C) The physical breakdown of rocks into smaller pieces without chemical change
D) The movement of rocks by wind and water.
C) The physical breakdown of rocks into smaller pieces without chemical change
What is chemical weathering?
A) The breakdown of rocks into smaller pieces without changing its composition
B) The breakdown of rocks through chemical reactions, often involving water and gases
C) The process of rocks being buried under sediment
D) The movement fo soil downhill
B) The breakdown of rocks through chemical reactions, often involving water and gases
What is dissolution, oxidation, and hydrolysis?
A) The types of physical weathering
B) The types of soil erosion
C) Types of volcanic eruptions
D) The types of chemical weathering
D) The types of chemical weathering
What affects rates of weathering?
A) Climate, rock type, surface area, and organisms
B) Only temperature
C) Only type of rock
D) Weathering happens at the same rate everywhere
A) Climate, rock type, surface area, and organisms
What is soil, why is it important, how is it formed, and how is it used?
A) Just small pieces of rock
B) The same everywhere
C) Formed only from chemical weathering
D) A mix of minerals and organic materials that support plant life
D) A mix of minerals and organic materials that support plant life
What role do parent material, time, climate, plants, and animals in the formation of soil?
A) They do not affect the soil formation
B) Only climate matters
C) They determine the composition, depth, and fertility of soil.
D) Soil forms instantly, without any external factors.
C) They determine the composition, depth, and fertility of soil.
What affects the rates of soil erosion, and what is the fate of eroded soil
A) A) Wind, water, vegetation, and human activity affect erosion, eroded soil is transported and deposited elsewhere.
B) Soil does not erode
C) Only wind causes erosion
D) All eroded soil disappears completely
A) A) Wind, water, vegetation, and human activity affect erosion, eroded soil is transported and deposited elsewhere.
What is diagenesis? Where does it occur, what types are there, and what sorts of things happen?
A) The breakdown of rocks by wind and water
B) The physical and chemical changes that turn sediment into rock, occuring underground
C) A type of volcanic eruption
The process of soil formation
B) The physical and chemical changes that turn sediment into rock, occuring underground
Describe the two types of lithification. Which rock types are formed by which process and how are chemical rocks formed?
A) Lava cools to form ingenious rocks, while pressure forms metamorphic rocks
B) Erosion removes sediment, while weathering breaks down rocks
C) Compaction presses sediment together while cementation binds particles with minerals
D) Chemical weathering dissolves minerals, while oxidation causes rust
C) Compaction presses sediment together while cementation binds particles with minerals
What are the biochemical and chemical varieties of limestone?
A) Limestone is only biochemical
B) Limestone forms from weathered igneous rocks
C) Limestone only forms in volcanic environments
D) Biochemical limestone comes from shells and coral, while chemical limestone forms from mineral precipitation
D) Biochemical limestone comes from shells and coral, while chemical limestone forms from mineral precipitation
Why is coal different from all other sedimentary rocks? How is it formed? Which are better for burning?
A) It is formed from lava and contains no organic material
B) It is organic, formed from plant material, and bituminous and anthracite burn best
C) It is made entirely of dissolved minerals
D) It is the only sedimentary rock that forms in the ocean
B) It is organic, formed from plant material, and bituminous and anthracite burn best
What is a sedimentary environment?
A) A location where sediment is deposited, such as rivers, oceans, or deserts
B) A place where magma cools
C) An area where rocks break down due to weathering
D) a volcanic zone
A) A location where sediment is deposited, such as rivers, oceans, or deserts
Continental, Marine, Transitional, what are their characteristics, and where are they found?
A) Transitional environments are found deep underground
B) Marine environments only include rivers
C) Continental is always underwater, marine is on land, and transitional is underground
D) Continental. includes rivers and deserts, marine is the ocean, and transitional Is near shorelines
D) Continental. includes rivers and deserts, marine is the ocean, and transitional Is near shorelines
Why do we care about sedimentary structures? What are the major types and their characteristics? Where and how are they formed?
A) We don’t
B) They form only in volcanic eruptions
C) They reveal past environments, including cross-bedding, ripple marks, and mud cracks
D) They exist only in metamorphic rocks
C) They reveal past environments, including cross-bedding, ripple marks, and mud cracks
