Exam One Study Guide Questions

The _____ division of The Geologic Time Scale is an era of the Phanerozoic eon.

Paleozoic

The total time period of "ancient life" is the _____ era

Phanerozoic

The division lines among eras (in the Geologic Time Scale) reflect major changes in the fossil record, including the extinction and appearance of new life forms. True or False?

True

The term Paleozoic describes an era of ancient life forms. True or False?

True

Aristotle and other prominent Greek philosophers were the first ones to promote the doctrine of Catastrophism. True or False?

True.

______ is often paraphrased as "the present is the key to the past"

Uniformitarianism.

What is the scientific name for the geologic process by which rocks break down in place to produce soils and sediments

Weathering

The asthenosophere ________

exists below a depth of 100 kilometers (60 mi)

the _____ is thought to be a liquid, metallic region in the Earth's interior.

outer core

The composition of the inner core of the Earth is thought to be ______

solid iron-nickel alloy

In an undeformed sequence of sedimentary rocks each bed is older than the one above and younger than the one below. The preceding is a statement of the law of ______

superpositon

The currently accepted age of Earth is ________ years.

4.6 Billion

What is "The Rock Cycle"

A conceptual model of the process of Uniformitarianism

Much of our modeling of Earth's interior comes from the study of seismic or earthquake waves. True or False?

True

Oceans cover 70% of the Earths surface. True or False

True

The Geologic Time Scale was devised before numerical dating using radioactivity was invented. True or False

True

Who was the highly influential, ancient Greek philosopher noted for his writings and teachings on natural philosophy and on the workings of Earth?

Aristotle

The ____- refers to the sum total of all life on Earth

Biosphere

___________, a popular natural philosophy of the seventeenth and early eighteenth centuries, was based on a firm belief in a very short geologic history for Earth.

Catastrophism

We now live in the ____ era

Cenozoic

What are the basic differences between the disciplines of physical and historical geology?

Historical geology involves the study of rock strata, fossils, and geologic events, utilizing the geologic time scale as a reference; physical geology includes the study of how rocks form and of how erosion shapes the land surface.

_____ rocks form by crystallization and consolidation of molten magma

Igneous

In correct order, from the center outward, Earth consists of which set of units?

Inner core, outer core, mantle, crust

Who is credited with formulating the doctrine of uniformitarianism?

James Hutton

Who was the important eighteenth century Scottish geologist and proponent of the doctrine of Uniformitarianism?

James Hutton

Consider the names of the eras in The Geologic Time Scale. What is meant by "zoic"?

Life and living things

The _____ forms the relatively cool, brittle plates of plate tectonics.

Lithosphere

Almost 90% of the earths geologic time (from the time it was gravitationally captured by our sun) is represented by the time span called _____

Precambrian Era

What type of rocks comprise 75% of Earths surface

Sedimentary

Which of the three rock types always originates on the surface of the solid Earth?`

Sedimentary

What is the fundamental concept of superposition?

Superposition: basic assumption, that in undeformed layers, oldest rock beds are at the bottom of sequence; or any sedimentary deposit accumulates on older rock or sediment layers.

Compared to the age of the Earth accepted as correct today, how did seventeenth and eighteenth century proponents of catastrophism envision the Earth's age?

They believed Earth to be much younger than current estimates.

According to the Rock Cylce, any type of rock may be transformed into another type of rock, given enough time. True or False

True

The thin, outer layer of Earth, down to a depth of 70 km (40 mi) in thickness, is called the ______

crust

The Geologic Time Scale division of eras are based on _________

major changes in the fossil record, including extinction and appearance of new life forms.

The asthenosphere is actually a part of the _____ of Earth

mantle