Earth Science Midterm Study Guide

Astronomy
Study of space, the universe, lunar phases, tides, eclipses
Meteorology
Study of weather, climate, atmosphere
Oceanography
Study of earth’s oceans
Geology
Study of earth and its processes, volcanoes, faults and folds, erosion, plate tectonics, and geologic history
Hypothesis
A possible explanation that can be tested. Shows relationship between the variables
Controlled experiment
An experiment that tests only one variable or factor at a time, keeping all other variables some or constant.
Control Group
The standard for comparing experimental effects. A trial in which there is no alteration to the independent variable
Independent Variable
The part of the experiment that is purposefully changed
Dependent Variable
The part that changes in response to the I.V. The thing that you’re measuring. Quantitative or Qualitative.
Levels
The independent variables that can affect change in the dependent variables
Map
A representation of the features of a physical body such as Earth
Reference point
A fixed place on the Earth’s surface from which direction & location can be described.
Compass
Shows the cardinal directions as well as combinations of these directions
True North
The direction to the geographic North Pole
Magnetic declination
The difference between the magnetic north and the true north
Latitude
The distance north or south from the equator; expressed in degrees
Longitude
The distance east and west from the prime meridian
Prime Meridian
The line that represents zero degrees longitude
Topographic Map
A map that shows surface features, or topography
Elevation
The height of an object above sea level
Contour Lines
Lines that connect points of equal elevation
Contour Interval
The difference in elevation between one contour line and the next
Relief
The difference in elevation between the highest & lowest points of the area being morphed
Index contour
A darker heavier contour line that is usually every 5th line and that is labeled by elevation.
Distortion
Changes in the distance, shapes & sizes of landmasses and oceans on maps
Cylindrical projection
A map projection that is made by moving the surface features of the globe onto a cylinder
Conical projection
A map projection that is made by moving the surface features of the globe onto a cone
Azimuthal projection
A map projection that is made by moving the surface features of the globe onto a plane
Title
Gives you info about the subject of the map
Compass rose
Shows you how the map is placed in relation to true north
Scale
Shows the relationship between the distance on Earth’s surface & the distance on the map
Legend
A list of the symbols used in the map & their explanations
Date
Gives you the time at which the information on the map was recorded
Remote sensing
The process of gathering and analyzing information about an object without physically being in touch with the object
Geographic Information System
GIS stands for
Ore
A mineral deposit large enough and pure enough to be mined for profit
Reclamation
The process of returning land to its original condition after mining is complete
Carat
The mass of a gemstone
Mineral
Inorganic, solid, naturally occurring, crystalline structure
Compound
Two or more elements that are chemically bonded together
Crystal
A solid whose atoms, ions, or molecules are arranged in a definite pattern
Luster
The way in which a mineral reflects light
Streak
The color of the powder of a mineral
Cleavage
The splitting of a mineral along smooth, flat surfaces
Fracture
The manner in which a mineral breaks along either curved or irregular surfaces
Hardness
A measure of the ability of a mineral to resist scratching
Element
A substance that cannot be separated or broken down into simpler substances by chemical means
Silicate mineral
A mineral that contains a combination of Si, O, and 1 or more metals
Nonsilicate mineral
A mineral that does not contain compounds of silicon and oxygen
Density
The ratio of the mass of a substance to the volume of the substance
Rock
A naturally occurring solid mixture of one or more minerals & organic matter
Rock Cycle
The continual process by which new rock forms from old rock material
Erosion
The process by which sediment is removed from its source
Deposition
The process in which sediment moved by erosion is dropped and comes to rest
Composition
The chemical make up of a rock; describes either the minerals or other materials in the rock
Texture
The quality of a rock that is based on the sizes, shapes, and positions of the rock’s grains
Intrusive Igneous Rock
Rock formed from the cooling & solidification of magma beneath the Earth’s surface
Extrusive Igneous Rock
Rock that forms as a result of volcanic activity at or near the Earth’s surface
Strata
Layers of rock
Stratification
The process in which sedimentary rocks are arranged in layers
Foliated
The texture of metamorphic rock in which the mineral rains are arranged in planes or bands
Non-foliated
The texture of metamorphic rock in which the mineral grains are not arranged in planes or bands
Natural resource
Any natural material that is used by humans, such as water, petroleum, minerals, forests, and animal
Renewable resource
A natural resource that can be replaced at the same make which the resource is consumed
Non-renewable resource
A resource that forms at a rate that is much slower than the rate at which it is consumed
Recycling
The process of recovering valuable or useful materials from waste or scrap; the process of reusing some items
Fossil fuel
A non-renewable energy resource formed from the remains of organisms that lived long ago
Petroleum
A liquid mixture of complex hydrocarbon compounds; used widely as a fuel source
Natural gas
A mixture of gaseous hydrocarbons located under the surface of the Earth, often near petroleum deposits; used as a fuel
Coal
A fossil fuel that forms underground from partially decomposed plant material
Acid precipitation
Rain, sleet, or snow that contains a high concentration of acids
Smog
Photochemical haze that forms when sunlight acts on industrial pollutants and burning fuels
Nuclear energy
The energy released by a fission or fusion reactions the binding energy of the atomic nucleus
Chemical energy
The energy released when a chemical compound reacts to produce new compounds
Solar energy
The energy received by the Earth from the sun in the form of radiation
Wind Power
The use of a windmill to drive an electronic generator
Hydroelectric energy
Electrical energy produced by falling water
Biomass
Organic matter that can be a source of energy; the total mass of the organisms in a given area
Gasohol
A mixture of gasoline and alcohol that is used as a fuel
Geothermal Energy
The energy produced by heat within the Earth
Reduce
Use less of a resource
Reuse
Find a new use for discarded products
Recycle
The recovering of valuable or useful material from waste or scrap
Uniformitarianism
A principle that states that geologic processes that occurred in the past that can be explained by current geologic processes
Catastrophism
A principle that states that geologic change occurs suddenly
Paleontology
The scientific study of fossils
Relative dating
Any method of determining whether an event or object is older or younger than other events or objects
Superposition
A principle that states that younger rocks lie above older rocks if the layers have not been disturbed
Geologic column
An arrangement of rock layers in which the oldest rocks are at the bottom
Unconformity
A break in the geologic record created when rock layers are eroded or when sediment is not deposited for a long period of time
Absolute Dating
Any method of measuring the age of an event or object in years
Isotope
An atom that has the same number of protons or the same number of as other atoms of the same element do but that has a different number of neutrons and thus a different atomic mass
Radioactive decay
The process in which a radioactive isotope tends to break down into a stable isotope of the same element or another element
Radiometric dating
A method of determining the age of an object by estimating the relative percentages of a radioactive parent isotope and a stable daughter isotope
Half-life
The time needed for half of a sample of a radioactive substance to undergo radioactive decay
Fossil
The remains or physical evidence of an organism preserved by geological processes
Trace fossil
A fossilized mark that is formed in soft sediment by the movement of an animal
Mold
A mark or cavity made in a sedimentary surface by a shell or other body
Cast
A type of fossil that forms when sediments fill in the cavity left by a decomposed organism
Index fossil
A fossil that is found in the rock layers of only one geologic age and that is used to establish the age of the rock layers
Geologic time scale
The standard method used to divide the Earth’s long natural history into manageable parts
Eon
The largest division of a geologic period
Era
A unit of geologic time that includes two or more periods
Period
A unit of geologic time into which eras are divided
Epoch
A subdivision of a geologic period
Extinction
The death of every member of a species
Crust
The outermost layer of the earth
Mantle
The layer of the Earth between the crust & the core
Core
The layer of the Earth that extends from below the mantle to the center of the Earth
Lithosphere
The outermost, rigid layer. 2 parts- crust & rigid upper part of the mantle. It’s divided into tectonic plates
Asthenosphere
A plastic layer of the mantle on which pieces of the lithosphere move. Made of solid rock that flows very slowly
Mesosphere
The strong, lower part of the mantle between the asthenosphere & the outer core
Outer core
The liquid layer of the Earth’s core that lies beneath the mantle & surrounds the inner core
Inner core
The solid, dense, center of our planet
Tectonic plate
Pieces of the lithosphere that move around on top of the asthenosphere
Continental Drift
The hypothesis that states that the continents once formed a single landmass, broke up, and drifted to their present locations
Sea-floor spreading
The process by which new oceanic lithosphere forms as magma rises toward the surface & solidifies
Plate tectonics
The theory that explains how large pieces of the Earth’s outermost layer move and change shape
Convergent boundary
The boundary formed by the collision of 2 lithospheric plates
Divergent boundary
The boundary between two tectonic plates that are moving away from each other
Transform boundary
The boundary between tectonic plates that are sliding past each other horizontally
Convection
The transfer of thermal energy by the circulation or movement of a liquid or gas
Compression
Stress that occurs when forces act to squeeze an object
Tension
Stress that occurs when forces act to stretch an object
Folding
The bending of rock layers due to stress
Anticline
Upward-arching folds
Syncline
Downward, trough-like folds
Monocline
Rock layers are folded so that both ends of the fold are horizontal
Fault
A break in a body of rock along which one block slides relative to another
Uplift
The rising of regions of the Earth’s crust to higher elevations
Subsidience
The sinking of regions of the Earth’s crust to lower elevations