Geog. Exam 3 Quiz Qs

The asthenosphere can best be described as a. a rigid solid. b. a liquid. c. plastic-like. d. plasma-like.

c. plastic-like.

Which of the following statements about Earth's core is false? a. It is composed primarily of iron. b. The inner core is believed to be liquid and the outer core solid. c. Temperatures in the core reach several thousand degrees. d. Temperatures and pressures are higher in the inner core than in the outer core.

b. The inner core is believed to be liquid and the outer core solid.

When geologists or archaeologists dig downward into a unit of rock or sediment, they are digging "back in time." This fact is based on the principle of ________. a. uniformitarianism b. superposition d. catastrophism

b. superposition

Which of the following is true regarding the geologic time scale? a. The bulk of Earth's history has occurred during the Cenozoic era. b. Over 87 percent of Earth's history has elapsed during the more recent Cenozoic, Mesozoic, and Paleozoic eras. c. Both relative and absolute dating methods are used in determining the sequence of the time scale. d. We live in the Tertiary period.

c. Both relative and absolute dating methods are used in determining the sequence of the time scale.

The boundary between the crust and the rest of the lithospheric upper mantle is a discontinuity known as the a. Gutenberg. b. mantle. c. Moho. d. lithospheric layer.

c. Moho.

Earth's interior is a. evenly mixed throughout. b. not subject to internal differentiation. c. heated unevenly by the heat of radioactive decay. d. arranged with lighter elements toward the center and heavier elements toward the crust.

c. heated unevenly by the heat of radioactive decay.

Knowledge of Earth's interior is derived from a. direct sampling of the interior using deep-test wells. b. work in Earth's deepest caverns and caves. c. indirect evidence involving the analysis of seismic waves. d. historic and prehistoric records.

c. indirect evidence involving the analysis of seismic waves.

The principles of buoyancy and balance, when applied to Earth's crust, helps us to explain fluctuations in Earth's outer crust, a property known as a. magnetism. b. Moho effect. c. isostasy. d. orogenesis.

c. isostasy.

Uniformitarianism assumes that a. Earth is quite young and is shaped by dramatic events. b. catastrophic episodes have regularly occurred. c. the same physical processes we see today are a key to understanding the processes that have been operating throughout geologic time. d. mountains, plains, and canyons formed by catastrophic events.

c. the same physical processes we see today are a key to understanding the processes that have been operating throughout geologic time.

Which of the following gives the correct sequence of layers in Earth, from the surface to the center? a. crust, core, lower mantle, asthenosphere b. asthenosphere, lower mantle, crust, core c. crust, lower mantle, asthenosphere, core d. crust, asthenosphere, lower mantle, core

d. crust, asthenosphere, lower mantle, core