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A material found in magma that is formed from the elements oxygen and silicon; it is the primary substance of Earth's crust and mantle
the point beneath Earth's surface where rock first breaks under stress and causes an earthquake
moment magnitude scale
a scale that rates earthquakes by estimating the total energy released by an earthquake
the buildup over time of nutrients in freshwater lakes and ponds that leads to an increase in the growth of algae
human-made gases containing chlorine and fluorine (also called CFCs) that are the main cause of ozone depletion
a brownish thick haze that is a mixture of ozone and other chemicals formed when pollutants react with sunlight
a form of oxygen that has three oxygen atoms in each molecule instead of the ususl two; toxic to organisms where it forms near the Earth's surface
rain or another from of precipitation that is more acidic than normal, caused by the release of molecules of sulfur dioxide and nitrogen oxide into the air
the layer of the upper atmosphere that contains a higher concentration of ozone than the rest of the atmosphere
an undersea mountain chain where new ocean floor is produced; a divergent plate boundary under the ocean
a deep valley along the ocean floor beneath which oceanic crust slowly sinks toward the mantle
the process by which oceanic crust sinks beneath a deep-ocean trench and back into the mantle at a convergent plate boundary
a section of the lithosphere that slowly moves over the asthenosphere, carrying pieces of contintental and oceanic crust
The theory that pieces of Earth's lithosphere are in constant motion, driven by convection currents in the mantle
law of superposition
the geologic principle that states that in horizontal layers of sedimentary rock, each layer is older than the layer above it and younger than the layer below it
the process in which radioactive elements break down, releasing fast-moving particles and energy
the name of the single landmass that began to break apart 200 million years ago and gave rise to today's continents
a type of fossil that is a hollow area in sediment in the shape of an organism or part of an organism
change over time; the process by which modern organism's have descended from ancient organisms
1. a group of related organisms that has died out and has no living members. 2. term used to describe a volcano that is no longer active and unlikely to erupt again
Give an account of; present in detail the characteristics by which an object or action can be recognized, or an event or process visualized
term used to describe metamorphic rocks that have grains arranged in parallel layers or bands
small, solid pieces of material that come from rocks or the remains of organisms; earth materials deposited by erosion
the process by which water, ice, wind, or gravity moves weathered particles of rock and soil
a type of rock that forms when particles from other rocks or the remains of plants and animals are pressed and cemented together
a type of rock that forms from an existing rock that is changed by heat, pressure, or chemical reactions
A vibration that travels through earth carrying the energy released during an earthquake
the liquid layer of the Earth's core that lies beneath the Mantle and surrounds the inner Core
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