After You Read

Word Detective: Scanning for Terms

Scan the article for the terms that correspond to the following clues. The clues follow the order in which the terms appear. Use the number of blanks as aids.

1. A word beginning with s that means " a bed or a layer". It derives from
Latin and is used in the text in its plural (Paragraph 1).

2. A two-word term that means " the attraction of bodies to the center of the
earth " (Paragraph 3).

3. A two-word term that means " longitudinal pressure waves in any
material medium" (Paragraph 5).

4. A word beginning with e that means " a shaking or trembling of the earth

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that is of the volcanic or tectonic origin (Paragraph 5).

5. A noun beginning with c that means " a flow of electric charges". Hint: is
often used with an adjective " electric" (Paragraph 6).

6. A word beginning with /-that means " an opposing force or the opposi­
tion by a body or substance to the passage of a steady electric current
through it" (Paragraph 6).

Recalling Information

Choose the correct word or phrase to complete the following sentences about the article.

1. When it is necessary to get a clearer picture of oil pool location (geolo-

gists/drillers/geophysicists) are called in.

2. The gravimeter is used to measure (the earth's weight/the earth's
gravity/the earth's magnetic field).

3. The reflected sound waves are recorded by (magnetometers/geophones/

gravimeters). *

4. Paleontologists study (fossils/earthquakes/sandstones).