Clues to Earth's Past Unit Review (Pt.2)

A(n) ________________________________is a surface where rock has eroded away, producing a break, or gap, in the rock record.

Matching rocks and fossils from separate locations is called ________________________________.

Eras are subdivided into____________________________, tens to one hundred million years in duration. Examples from the Mesozoic Era are the Triassic, Jurassic, and Cretaceous.

___________________________________ is the separation of a population of organisms from the rest of its species due to some physical barrier, such as a mountain range or an ocean. Separated populations of species may evolve in different ways.

Eons are subdivided into smaller units of time called ______________, which generally span around a hundred million years. These are separated by catastrophic extinction boundaries.

The _________________________ is the current geologic eon in the geologic time scale, and the one during which abundant animal and plant life has existed. It covers 541 million years to the present, and began with the Cambrian Period.

Periods are subdivided into ____________________, tens of millions of years in duration. Currently, we are in the Holocene, which began about 10,000 years ago.

According to the________________________, if one geologic feature cuts across another feature, the feature that it cuts across is older.

Match it! Select the correct answer from the pull down...Good luck!