After three half-lives, one-ninth of an original radioactive parent isotope remains, and eight-ninths has decayed into the daughter isotope.
answer
FALSE
question
The era known as the "age of mammals" is the ________ era.
answer
Cenozoic
question
About 88 percent of geologic time is represented by the time span called the ________.
answer
Precambrian
question
Visualize five horizontal sedimentary strata exposed in a cliff or canyon wall identified by consecutive numbers, 1 being the lowest bed and 5 being the highest. Which of the following statements concerning the strata are true?
answer
Beds l and 3 are older than bed 4.
question
After two half-lives, there is no longer any of the original radioactive material remaining.
answer
FALSE
question
There is geologic evidence that the earth has experienced many episodes of mountain building and erosion.
answer
TRUE
question
Petrified wood is an example of a fossil formed by ________.
answer
permineralization replacing original cellulose of the wood
question
The era of "ancient life" is the ________ era.
answer
Paleozoic
question
Which of the following is not a very long-lived, radioactive isotope?
answer
C-14
question
An unconformity is a buried ________.
answer
surface of erosion separating younger strata above from older strata below
question
An important tool in understanding the actual numerical dates of past geologic events is ________.
answer
Radioactivity
question
Explain the principle of uniformitarianism and discuss how it differs from catastrophism.
answer
Uniformitarianism is the concept that the processes that have shaped earth in the geologic past are pretty much the same as the ones today, whereas catastrophism is the idea that earth was shaped by catastrophic events of a short-termed nature.
question
Describe at least 3 ways that an animal or plant can be preserved as a fossil.
answer
They can be preserved by permineralization, molds or casts, carbonization, or amber.
question
Which of the following organisms would be most likely to be preserved in the geologic record?
answer
a clam with a thick calcite shell that lived on a mudflat
question
Which of the following is an essential characteristic of an index fossil?
answer
The organism only lived for a short period of geologic time.
question
In the late 1800's various principles (original horizontality, inclusions, cross cutting relations, etc.
arête) were established and used to ________.
answer
organize the order in which events occurred on earth
question
What is the age of the Earth accepted by most scientists today?
answer
4.6 billion years
question
Numerical dates based on radioactivity are very important for studying Precambrian geologic history because fossils are rare or absent.
answer
TRUE
question
Which of the following denotes the divisions of the geologic time scale in correct order of decreasing lengths of time beginning with the longest time interval and ending with the shortest?
answer
eon, era, period, epoch
Haven't found what you need?
Search for quizzes and test answers now
Quizzes.studymoose.com uses cookies. By continuing you agree to our cookie policy
