geo 1 Flashcards
What are the basic differences between the disciplines of physical and historical geology?
Physical geology examines Earth’s materials and processes, while historical geology focuses on Earth’s past and the development of life.
A ________ is a well-tested and widely accepted view that best explains certain scientific observations.
Theory
The ________ division of the geologic time scale is an era of the Phanerozoic eon.
A) Proterozoic B) Paleozoic C) Paleocene D) Permian
B) Paleozoic
The asthenosphere is actually a part of the ________ of the Earth.
A) mantle B) inner core C) crust D) outer core
A) mantle
The most prominent features on the ocean floor are the ________.
Mid-ocean ridges
The ________ refers to the sum total of all life on Earth.
A) biosphere B) hydrosphere C) atmosphere D) asthenosphere
A) biosphere
What does NOT provide evidence or clues to the composition of Earth’s interior?
A) comets B) diamond-bearing rocks C) slivers of crustal and mantle rocks now exposed at Earth’s surface D) meteorites
A) comets
Active mountain belts are most likely to be found where on the continents?
Along plate boundaries
________ is the process by which rocks break down in place to produce soils and sediments.
Weathering
The ________ is not a part of Earth’s physical environment.
The Sun
The composition of the core of Earth is thought to be ________.
Iron and nickel
The continental shelf is located ________.
Along the edges of continents, extending into the ocean
________ rocks form by crystallization and consolidation of molten magma.
Igneous
The ________ is thought to be a liquid, metallic region in the Earth’s interior.
Outer core
A ________ system is one in which energy moves freely in and out, but no matter enters or leaves the system.
Closed
________ plate boundaries have the largest magnitude earthquakes.
Convergent
The continental drift hypothesis was rejected primarily because Alfred Wegener could not do what?
Explain the mechanism for movement of continents
Deep-oceanic trenches are most abundant around the rim of the ________ ocean basin.
Pacific
Deep ocean trenches are surficial evidence for ________.
Subduction zones
What are the differences between the asthenosphere and the lithosphere?
The lithosphere is rigid and brittle, while the asthenosphere is ductile and flows slowly.
The ________ is (are) a logical evolutionary analog of the African Rift Valleys ten million years from now.
Red Sea
The Aleutian Islands occur at what sort of plate boundary?
Convergent boundary (ocean-ocean)
What most accurately describes the type of large volcanoes of the Hawaiian Islands?
Shield volcanoes
Cooler, older oceanic lithosphere sinks into the mantle at ________.
Subduction zones
What energy sources are thought to drive the lateral motions of Earth’s lithospheric plates?
Mantle convection, slab pull, and ridge push
The former, late Paleozoic supercontinent is known as ________.
Pangaea
What paleoclimatic evidence supports the idea of the late Paleozoic supercontinent in the Southern Hemisphere?
Glacial deposits and striations found in now widely separated continents
The modern-day Red Sea is explained by plate tectonics theory because it is ________.
An active divergent boundary
What defines a mineral and what defines a rock?
A mineral is a naturally occurring, inorganic solid with a definite chemical composition and crystalline structure. A rock is an aggregate of minerals.
Can liquid mercury, occurring naturally on the surface, be regarded as a mineral? How about crude oil?
No, because minerals must be solid. Crude oil is not a mineral because it is organic.
What is a typical product of weathering?
Clay minerals
All silicate minerals contain which two elements?
Silicon (Si) and Oxygen (O)
What are isotopes?
Variants of an element that differ in neutron number but have the same number of protons
Which terms describe light reflecting and transmission characteristics of a mineral?
Luster and transparency
What is the unit of weight used for measuring diamonds (about 0.2 grams)?
Carat
What is the name of dark-colored mica?
Biotite
Chrysotile, crocidolite, and amosite are different mineralogical forms of what industrial commodity?
Asbestos
Which mineral is easily soluble in water at room temperature conditions?
Halite (salt)
The ion at the center of a silicate tetrahedron is surrounded by ________.
Four oxygen atoms
What are factors that affect the generation of magma?
Temperature, pressure, and water content
A (an) ________ texture represents a single, long period of cooling and crystallization.
Phaneritic
Which igneous rock has a pyroclastic texture?
Tuff
Visible quartz and potassium feldspar grains are the main constituents in a ________.
Granite
A ________ is an open cavity in a volcanic rock that was filled by a gas bubble when the lava was still mainly liquid.
Vesicle
The last minerals to crystallize on Bowen’s Reaction Series result in igneous rocks with a ________ composition.
Felsic
________ is a volcanic rock that is extremely vesicular and glassy.
Pumice
________ is the dominant feldspar in basalt.
Plagioclase
Which minerals crystallize early in Bowen’s reaction series?
Olivine and pyroxene
________ magma is the most abundant type of magma erupted at oceanic spreading centers.
Basaltic
The 1991 Pinatubo eruption in the Philippines caused brilliantly colored sunrises and sunsets to be seen for the next few years. What caused this phenomenon?
Volcanic ash and aerosols scattering sunlight
Which kind of eruptive activity is most likely to be highly explosive?
Stratovolcano (composite volcano) eruptions
