Chapter 2 Vocabulary

Continent

landmasses above water on Earth.

Solar System

consists of the sun and nine known planets, as well as other celestial bodies that orbit the sun.

Core

the center of the Earth and is made up of iron and nickel.

Mantle

surrounds the core and contains most of the Earth's mass.

Magma

molten rock

Crust

the thin layer of rock at the Earth's surface.

Atmosphere

a layer of gases surrounding the Earth which contains the oxygen we breathe, protects the earth from radiation and space debris, and provides the medium for weather and climate.

Lithosphere

the solid rock portion of the Earth's surface which includes the crust and uppermost mantle.

Hydrosphere

made up of the water elements on the earth, which include oceans, seas, rivers, lakes, and water in the atmosphere.

Biosphere

the part of the Earth where plants and animals live...it consists of the atmosphere, the lithosphere, and the hydrosphere.

Continental Drift

a theory presented by Alfred Wegener of Germany in 1912 that maintains the earth was once a supercontinent (Pangaea) that divided and slowly drifted apart over millions of years

Hydrologic Cycle

the continuous circulation of water between the atmosphere, the oceans, and the earth.

Drainage Basin

an area drained by a major river and its tributaries.

Ground Water

the water that is held in the pores of rock.

Water Table

the level at which the rock is saturated.

Landform

naturally formed features on the surface of the earth.

Continental Shelf

the earth's surface from the edge of a continent to the deep part of the ocean.

Relief

the difference in elevation of a landform from its lowest point to its highest point.

Topography

the combination of the surface shape and composition of the landforms and their distribution in a region.

Tectonic Plate

enormous moving pieces of the earth's lithosphere.

Fault

fracture in the earth's crust

Earthquake

violent movement of the earth.

Seismograph

measures the size of the energy waves created by an earthquake.

Epicenter

the point above the focus on the earth's surface.

Richter Scale

uses information collected by seismographs to determine the relative strength of an earthquake.

Tsunami

a giant wave in the ocean.

Volcano

occurs when magma, gases, and water from the lower part of the crust or mantle collects in underground chambers and eventually pour out of the earth's surface.

Lava

magma that has reached the earth's surface.

Ring of Fire

active volcanoes located around the rim of the Pacific Ocean.

Weathering

refers to the physical and chemical processes that change the characteristics of rock on or near the earth's surface.

Sediment

identifiable as mud, sand, or silt, which are very fine particles of rock.

Mechanical Weathering

processes that break rock into smaller pieces.

Chemical Weathering

processes that change rock into a new substance as a result of interactions between elements in the air or water and the minerals in the rock.

Erosion

the reshaping of landforms, coastal regions, riverbeds, and river banks that occurs when weathered material is moved by the action of wind, water, ice, or gravity.

Delta

a fan-like landform made of deposited sediment, left by a river that develops as it enters the ocean.

Loess

windblown silt and clay sediment that produce very fertile soil.

Glacier

a large, long-lasting mass of ice that moves because of gravity.

Glaciation

the changing of landforms by slowly moving glaciers

Moraine

rocks left behind by glaciers which may form ridges or hills.

Humus

organic material in the soil.