Exam 24: Geologic Time

Primordial lead contains the isotope lead-______________,whereas radiogenic lead does not.

The term age of reptiles is sometimes used to refer to the ______________ era.

Fossils that are useful in correlating rock layers are called

The term age of mammals is sometimes used to refer to the ______________ era.

The fundamental concept of geology that was developed by James Hutton is

The process of matching up rock layers in different localities by the use of index fossils or other means is called ______________.

The Cenozoic era consists of the Tertiary and ______________ periods.

Which of the following is a period of the Cenozoic era?

______________ dating is used specifically to establish the absolute age of organic remains.

The earliest evidence of prehistoric life is the single-celled organisms called ______________.

The Paleozoic is a(n)

Geology's best tool for establishing absolute (numerical)geologic time is called ______________ dating.

The process of matching up rock layers in different localities by such means as index fossils is called

Amber is fossilized

The K-T event occurred about ______________ million years ago.

Tracks,borings,and burrows are examples of

The Cenozoic era began about how many million years ago?

A dike that intrudes a bed of sedimentary rock is ______________ than the sedimentary rock.

A lava flow radiometrically dated at 300 million years lies just below sedimentary layer A and just above sedimentary layer B.What can be said of the ages of beds A and B?

The Paleozoic era began about how many million years ago?