Exam 11: Geologic Time

The ________ is the idea or concept that ancient life forms succeeded each other in a definite,evolutionary pattern and that the contained assemblage of fossils can determine geologic ages of strata.

Compare and contrast relative age dating with radiometric age dating.What is a limitation (if any)of each?

An unconformity is a buried ________.

The remains or traces of prehistoric life are called ________.

Which of the following organisms would be most likely to be preserved in the geologic record?

An important geochronometer is the decay of 147Sm to 143Nd.What type of radioactive decay is involved in this parent-daughter pair?

electron capture alpha emission delta capture beta emission

If you observe a disconformity,you would infer that the region had experienced ________.

Petrified wood is an example of a fossil formed by ________.

For a radioactive isotope like Uranium-235,what does the 235 indicate?

Strata above an angular unconformity were tilted before the older strata were eroded.

Different periods of the geologic time scale are different in length.Why?

Which of the following refers to the investigative process by which geologists identify and match sedimentary strata and other rocks of the same ages in different areas?

Most sedimentary rocks are readily dated by radiometric methods.

All of geologic time prior to the beginning of the Paleozoic era is termed the Phanerozoic eon.

Unconformities which represent a break in the geologic record of deposition are important because ________.

The basic concept of Uniformitarianism is ________.

One method to obtain the absolute age of a sedimentary rock is to obtain a radiometric date on an interbedded volcanic rock.

The principle of cross-cutting relationships which states that a geologic feature that cuts across another feature must be younger than the feature it cuts is important because ________.

The principle of inclusions which states that the source of rock fragments found in a unit must be older than the unit with the fragments is important because ________.