Recent—the present [epoch] of geologic time; the second epoch of the [Quaternary] [Period] (see [p. 3]).

Sectile—describes material, such as soap, that can be cut smoothly with a knife.

Sediments—material deposited by water, wind, or ice on the earth’s surface.

Sedimentary rocks—rocks made up of [sediments].

Series—a subdivision of a [system] that includes all rocks formed during an [epoch].

Specific gravity—the ratio of the weight of a substance to the weight of an equal volume of water.

Streak—the color of the powder of a mineral.

System—all rocks formed during a [period].

Tertiary—the first [period] of the [Cenozoic] [Era] (see [p. 3]).

Translucent—light will pass through, but objects cannot be seen.