Geology Final Exam

A stream starts at 200 meters above sea level and flows 400 kilometers to the ocean. Calculate gradient.

0.5 m/km

A typical rate of seafloor spreading in the atlantic ocean is

2 cm per year

The age of Earth is about ________.

4.5 billion years

________ is NOT part of the hydrologic cycle.

Calcium carbonate dissolving in soil water and groundwater

Extrusive igneous rocks are typically finer grained than intrusive igneous rocks. Why?

EX cools quickly so the mineral grains do not have time to grow

Water in Earth's early oceans came from ________.

Earth's interior, rising up through fissures in the crust

Which of the following best defines a mineral and a rock?

Minerals have atoms are arranged with structure; in rocks atoms are random

A well-tested and widely accepted view that best explains certain scientific questions

Theory

Which statement concerning sedimentary rocks is NOT true?

They were originally deposited at depth beneath Earth's surface

The water table is ________.

a boundary between saturated rock below and unsaturated rock above

The asthenosphere is...

a relatively weak zone within the mantle

The reflectivity of surfaces is called ________.

albedo

________ magma is the most abundant type of erupted at oceanic spreading centers.

basaltic

The ________ refers to the sum total of all life on Earth.

biosphere

Which common, rock-forming mineral or mineral group is most readily dissolved by groundwater?

calcite

Which of the following is/are most susceptible to chemical weathering by dissolution?

calcite

The strong tendency of certain minerals to break along smooth, parallel planes is known as ________.

cleavage

Lowering of the water table around a pumping well results in a ________.

cone of depression

Most of Earth's strongest earthquakes tend to occur along ________.

convergent plate boundaries

Which of the following is an Earth layer defined based on the chemical composition?

crust

Metamorphism typically occurs ________.

deep beneath earth's surface

________ are NOT associated with a mid-ocean ridge.

deep ocean trenches

Folds form as a result of ________.

ductile deformation

The position on Earth's surface directly above the earthquake source is called the ________.

epicenter

True or false? Sedimentary rocks may weather to igneous rocks

false

Which contains the highest percentage of Earth's liquid freshwater?

groundwater

A very long-lived magma source located deep in the mantle is called a ________.

hot spot

How does urbanization (paving, etc.) affect runoff and infiltration in a small, previously forested, drainage basin?

infiltration decreases; runoff increases

Currents within the surf zone that flow parallel to the shore are known as ________ currents.

longshore

All of the following are possible consequence of global warming, EXCEPT:

lowering of sea level

Which of the following describes the light reflecting characteristics of a mineral?

luster

The asthenosphere is actually a part of the_________

mantle

The downslope movement of rock, regolith, and soil is called ________.

mass movement

The two basic categories of weathering are ________.

mechanical and chemical

At subduction zones, is the portions of oceanic crust older or younger that descend into the mantle?

older

Which of the following gases was not part of Earth's original atmosphere?

oxygen

Deep-oceanic trenches are most abundant around the rim of the ________ ocean basin.

pacific

The primary basis for distinguishing among detrital sedimentary rocks is ________.

particle size

The major source of free oxygen in the atmosphere is from ________.

plants

________ Eon accounts for ~90% of the geologic time scale.

precambrian

What rock type always originates at the surface?

sedimentary

Most of our knowledge about Earth's interior comes from ________.

seismic waves

A ________ volcano is a very large, gently sloping mound composed mainly of basaltic lava flows.

shield

What are deep ocean trenches surficial evidence for

sinking of oceanic lithosphere into the mantle at a subduction zone

Sorting refers to the range of particle ________ in a rock.

sizes

Overall, this type of seismic wave is the most destructive.

surface waves

The sizes, shapes, and arrangements of mineral grains in an igneous rock are known as ________.

texture

Deep-ocean circulation currents are referred to as ____________ circulation.

thermohaline

What two factors speed up rates of chemical reaction and weathering in rocks and soils?

warm temperatures and very moist

________ are usually the most abundant gases typically released during volcanism.

water vapor and carbon dioxide

What is the process by which rocks break down in place to produce soils and sediments?

weathering