CHAPTER 11 Key Terms
Match each of the terms on the left with its definition on the right. Click on the term first and then click on the matching definition. As you match them correctly, they will move to the bottom of the activity.
absolute age Anthropocene asthenosphere basalt continental crust crust cyanobacteria earthquake granite inner core lava lithosphere magma magnetosphere mantle Moho oceanic crust outer core radiometric dating relative age seismic wave superposition uniformitarianism volcano | An age that is specified in years before the present. The crust that makes up the continents, composed mainly of granite. The principle that the same imperceptible gradual processes are operating now and have operated in the past. A silica- The principle that in a sequence of rock layers, the oldest rocks are always at the bottom and the youngest at the top. The layer of heated and slowly deforming solid rock between the base of the crust and the outer core. A method of assigning absolute ages to Earth materials based on the radioactive decay of unstable elements in those materials. The outer edge of the magnetic field that surrounds Earth and shields it from the solar wind. The innermost layer of Earth, composed of solid iron and nickel. A sudden shaking of the ground caused by movements of Earth’s crust. A dark, heavy, fine- The boundary that separates the crust from the lithospheric mantle, which lies about 35 km (22 mi) deep on average. The rigid outermost portion of Earth’s surface. The second innermost layer of Earth, composed of a liquid alloy of iron and nickel, which generates Earth’s magnetic field. Energy released by an earthquake that travels through Earth’s interior as a wave. The age of one object or event in relation to the age of another without regard to how old either is. The crust beneath the oceans, composed mainly of basalt. Hot molten rock that spills onto the surface of Earth’s crust. Photosynthetic bacteria that were among the first forms of life to evolve about 3.5 billion years ago. (pronounced an- A mountain or hill formed by eruptions of lava and rock fragments. The layer of the mantle, which deforms and flows, found between about 100 and 200 km (62 and 124 mi) in depth. Melted rock that is below the surface of Earth’s crust. The layer of Earth that consists of the rigid crust and the rigid lithospheric mantle beneath it, extending to a depth of about 100 km (62 mi) on average. |