Plate Boundaries Review

Which of the following is the densest layer of the solid Earth?

• atmosphere
• core
• mantle
• crust

The Earth's core is made of two parts - the inner and outer core. The inner core is made mostly of

• liquid metal.
• nonmetallic liquid.
• nonmetallic gas.
• solid metal.

The asthenosphere and the lithosphere are layers of the Earth that are contained within the mantle. The asthenosphere is a plastic layer that lies beneath the lithosphere. It is formed of mantle rock that flows slowly which allows the tectonic plates to move. The lithosphere is stiffer and floats on top of the asthenosphere like ice on water. Given this information, the Earth's mantle must have properties of

• solids and liquids.
• solids and gases.
• liquids and gases.
• liquids.

Who is the scientist that developed the theory of Continental Drift?

• Harry Hess
• Sir Isaac Newton
• Alfred Wegener

Most geologists rejected his idea of continental drift because...

• he was interested in what Earth was like millions of years ago.
• he used several different types of evidence to support his hypothesis.
• he could not identify a force that could move the continents.

It has been theorized that all of the modern continents on Earth were once part of a single continent. What scientific evidence is used to support this theory? Check all that apply.

• fossil evidence of identical plants and animals found on both sides of the Atlantic Ocean
• glacial deposits, marks, in southern Africa, South America, India, and Australia
• the Atlantic coasts of South America and Africa appeared to fit together
• similar geologic features, such as mountain ranges
• some of the continents that exist today have similar types of rocks.

Which of the following is true about Earth's continents?

• The positions of the continents did not change in the past and are not changing today.
• The positions of the continents did not change during Earth's past, but they are changing today.
• The positions of the continents have continually changed over time and continue to change today.
• The positions of the continents continually changed over time in the past, but they are no longer changing today.

Before the present theory of plate tectonics, scientists used the hypothesis of continental drift to propose that Earth's continents are in motion. Which of the following were initially used to support the hypothesis of continental drift? I.the matching shapes of continent edges II.similar fossils on different continents III.matching rock types on different continents IV.evidence in the rock record for climate change

• II and III only
• I and IV only
• II, III, and IV only
• I, II, III, and IV

The early hypothesis of _______ was based on observations that suggested continents were once joined together. Later, the theory of _______ explained why large pieces of Earth's surface move around and how many of Earth's features form.

• continental drift; plate tectonics
• plate tectonics; continental drift
• plate tectonics; gravitational force
• gravitational force; continental drift

The theories of continental drift and sea-floor spreading combined to make the theory of _______.

• supercontinents
• plate tectonics
• rejoined continents
• Pangaea