Geology chap 3.

The Earth is 4.5 billion years old, but the oldest surviving rocks only go back 4.0 billion years. However, geologists have extended the rock record by finding small zircon (ZrSiO4) crystals as old as 4.4 billion years. In which of the following rock types do geologists find these ancient zircon crystals?

Clastic sedimentary

Which of the following statements best describes extrusive igneous rocks?

Cool on the surface and have a fine-grained texture (small mineral crystals)

Which of the following terms do geologists use to describe the process whereby rocks are mechanically broken down into smaller pieces?

Physical weathering

Which of the following is NOT true regarding clay minerals?

Precipitate out of magmas.

Which of the following is an example of how chemical sedimentary rocks form?

Precipitation of dissolved ions as a water body evaporates.

What elements makeup most of the rocks in Earth's crust?

Silicon and Oxygen

Which of the following statements best describe what geologists refer to as rock-forming minerals?

The few dozen or so minerals that make up most of the rocks in Earth's crust.

Prehistoric humans used the mineral chert to make stone tools. Which of the following physical properties made chert useful for this application?

Very hard and creates sharp edges when broken

Many types of sedimentary rocks are deposited along the continental shelf. Which of the following best explains why limestones commonly form further offshore compared to other sedimentary rocks?

Water has less suspended sediment

frost-wedging

When water creeps into the cracks of rocks then freeze causing the rock to crack. This is an example of physical weathering.

Which of the following best explains how foliated metamorphic rocks form?

by increased pressure

Limestone (sedimentary) is dominated by

calcite

Which of the following type of rocks would be most susceptible to being broken down by the weathering process known as dissolution?

chemical sedimentary

Shale (sedimentary) is dominated by

clay minerals

Which of the following best explains why rocks can be used to interpret the geologic past?

different types of rocks form in different types of environments

Physical weathering causes rocks to ________, whereas chemical weathering refers to ________.

disintegrate into smaller particles by some mechanical process, the decomposition of minerals via chemical reactions

Which of the following is NOT a subatomic particle found in the nucleus of atoms?

electrons, only contain protons and neutrons

The Rock Cycle illustrates how different rock types can be transformed into other rock types. Which of the following best describes the process by which igneous rocks are transformed into sedimentary rocks?

erosion and weathering

The Rock Cycle illustrates how different rock types can be transformed into other rock types. Which of the following best describes the process by which metamorphic rocks are transformed into igneous rocks?

extreme heat

All metamorphic rocks have a foliated texture.

false

Earth's crustal rocks have a higher density compared to the Earth as a whole.

false

basalt cooling history

fast cooling, fine-grain texture, extruded on the surface

Basalt (igneous) is dominated by

feldspar and ferromagnesian minerals

Granite (igneous) is dominated by

feldspar, quartz, and micas

Which of the following is NOT a type of chemical reaction that breaks down minerals?

fusion

The Rock Cycle illustrates how different rock types can be transformed into other rock types. Which of the following best describes the process by which igneous rocks are transformed into metamorphic rocks?

heat and pressure

Which of the following best describes how metamorphic rocks form?

increased pressure and temperature

obsidian cooling history

instant cooling, glassy texture, extruded in waterbody

Which of the following best describes what happens when a sedimentary rock is heated to the point it completely melts and later re-crystallizes?

it becomes an igneous rock

When using rocks to study Earth's history, information about the surface environment is best provided by which of the following types of rock?

limestone and shale

Sandstone (sedimentary) is dominated by

quartz

Marble (metamorphic) is dominated by

recrystallized calcite

Quartzite (metamorphic) is dominated by

recrystallized quartz

Schist (metamorphic) is dominated by

recrystallized quartz and micas

Which of the following is an example of a detrital sedimentary rock?

sandstone

granite cooling history

slow cooling, coarse-grain texture, intruded below surface

All minerals have a unique combination of internal structure and chemical composition. The structure and chemistry of minerals determines what?

the physical and chemical properties of minerals

Geologists are able to study processes that form rocks here on Earth and then use this information to help interpret the geologic history of other planets.

true

The term lava is used to refer to molten rock that makes its way onto Earth's surface environment.

true