PHY2253 Chapter 24 Reading Worksheet
How Well Have You Read Chapter 24? Use this worksheet as a guide in your reading of Chapter 19. If you use
this worksheet correctly, it will also serve as a nice study guide for this chapter. Complete the “Answer” column
using words and phrases from your textbook. In the column labeled “page number”, enter the page Shipman text
where the answer to the item is first found. For each True/False question, I suggest you also explain the reasoning
in the answer column, so that when you look back on this to study, you remember why you chose ‘true’ or ‘false’.
STATEMENT
A(n) ______________ is any indication of
prehistoric life preserved in rock.
The study of fossils is called ______________.
The hollow depression left when a shell or bone is
dissolved completely out of a rock is called a(n)
______________.
The earliest evidence of prehistoric life is the
single-celled organisms called ______________.
A fossil imprint made by the movement of an
animal is called a(n) ______________ fossil.
When rocks and geologic events are placed in
chronological order without regard to actual
dates, ______________ geologic time is obtained.
The ______________ states that in a sequence of
undisturbed sedimentary rocks, lavas, or ash, each
layer is younger than the layer beneath it.
The process of matching up rock layers in different
localities by the use of index fossils or other means
is called ______________.
The largest units of geologic time are called
______________.
The time before the Phanerozoic eon is
collectively called ______________ time.
We live in the ______________ eon.
The term age of reptiles is sometimes used to
refer to the ______________ era.
The term age of mammals is sometimes used to
refer to the ______________ era.
The term age of ancient life is sometimes used to
refer to the ______________ era.
Eras are divided first into smaller time units called
______________.
The Jurassic period is part of the ______________
era.
Much of our energy comes from coal that was
formed from plants that lived during the
______________ period.
ANSWER
PAGE #
PHY2253 Chapter 24 Reading Worksheet
The actual age of rock layers and geologic events is
referred to as ______________ geologic time.
The concept of uniformitarianism was developed
by ______________, the "father of geology."
Atomic nuclei that decay of their own accord are
said to be ______________.
The span of time required for the radioactive
decay of half the parent nuclei in a sample is
known as the ______________.
Naturally occurring uranium ultimately decays to
isotopes of the element named ______________.
Primordial lead contains the isotope lead______________, whereas radiogenic lead does
not.
Rubidium-______________ dating is an important
radiometric dating tool.
Carbon dating was used to establish the age of the
Shroud of ______________.
Lack of knowledge of the phenomenon called
______________ led Lord Kelvin to an incorrect
estimate of the age of Earth.
Relative and absolute geologic times are combined
to give the ______________ scale.
The Phanerozoic eon and the Paleozoic era began
about ______________ million years ago.
The Paleozoic era ended and the Mesozoic era
began about ______________ million years ago.
The periods of the Cenozoic era are divided into
time units called ______________.
The finding of an abnormally high concentration of
the element named ______________ was the first
clue to the probable cause of the K-T event.
The Cenozoic era consists of the Tertiary and
______________ periods.
Sea lilies are more scientifically called
_________________.
Layers of sediment, lava, and ash are originally laid
down in a(n) ______________ position
A dike that intrudes a bed of sedimentary rock is
______________ than the sedimentary rock.