8th Grade Science: Chapter 4

What is the lower limit of the temperature range for metamorphism?

150 to 200 Celsius

Conglomerate rocks were deposited in what kind of environment?

A River channel

Sandstone has what kind of texture that is classic in clastic rocks?

A gritty texture like sugar

What are igneous rocks's composition?

A variety of minerals and appear MULTICOLORED

Chemical sedimentary rocks often have what kind of texture?

An interlocking crystalline texture similar to many igneous rocks

Processes that involve extreme heat and pressure or melting occur only above ground or below ground ?

Below ground

What kind of textures can metamorphic rocks have?

Blocky, interlocking crystals uniform in size and color

Ice can move what size of clasts?

Both large and small

When rocks are exposed to earth's surface, they can.....................

Break down and be transported to new environments

Small, gritty sediment is deposited in which environments?

Calm places such as the sea floor or the bottom of a lake

What does contact metamorphism do to rocks?

Can increase crystal size or from new minerals and change rock.

Limestone is what kind of rock?

Carbonate sedimentary rock

What are some factors that play a big role in creating metamorphic (and igneous) rocks?

Changes in temperature, pressure, or the addition of chemical fluids which RESULTS IN the rearrangement of minerals or the formation of new minerals

Geologists identify clastic rocks by their

Clast size and shape

What are chemical sedimentary rock's composition?

Composed of one dominant mineral and is UNIFORM IN COLOR

What is an example of a sedimentary rock that has well rounded rock fragments?

Conglomerate rocks

What is 1 way to form a non-foliated rock?

Contact metamorphism

What kind of minerals distinguish metamorphic rocks from clastic sedimentary rocks?

Crystalline minerals

When magma or lava cools, what forms to create what type of rock?

Crystals form to create igneous rocks

What contributes to the saltiness of seawater?

Dissolve minerals entering the ocean or sea

Sedimentary rocks can form during

Evaporation when minerals crystallize from water or when organisms remove minerals form the water to make their shells or skeletons

If the crystals of an igneous rock are small or impossible to see without a magnifying lens, the rock is (Extrusive/Intrusive)

Extrusive

Extrusive igneous rocks have course or fine grained texture?

Fine-grained

What is limestone with fossils in it called?

Fossiliferous limestone

Sediment can transported by...

Glacial ice

The rock granite metamorphoses into.........

Gneiss

What is an example of an igneous rock and its composition?

Granite - made of quarts, feldspar, & mica

What effect do the gasses that escape magma have on the rocks left behind?

Holes are created, like in Pumice

Extrusive rocks

Igneous rocks formed when volcanic material erupts and cools and crystallizes on Earth's surface

Intrusive rocks

Igneous rocks that form as magma cools underground

Metamorphic rocks can form from what other types of rocks?

Igneous, sedimentary, and other metamorphic rocks

If the crystals of an igneous rock are large enough to see and have interlocking texture, the rock is (Extrusive/Intrusive)

Intrusive

Why is limestone a type of carbonate sedimentary rock?

It contains the elements carbon and oxygen

What kind of texture does Rock Schist have?

It is foliated and has light and dark colored layers

How is crystalline texture in metamorphic rocks different than in igneous rocks?

It is uniform in color instead of multicolored like granite

Pressure in measured in what unit?

Kilo-bars (kg)

When magma cools slowly, what kind of crystals form?

Large, well defined crystals

Fast flowing River and ocean waves tend to move what sized sediment?

Larger sediment

Materials such as _____________________ solidify and form extrusive rocks

Lava and ash

Sediments accumulate in....

Layers

What is the most common biochemical rock?

Limestone

Large amounts of magma cool and crystallize underground, though this process is

Longer

When a geologist classifies a rock by its texture, he or she.....................

Looks at the size of the minerals or grains in the rock, the arrangement of these individual grains, and the overall feel of the rock

Geologists conduct fieldwork by using what tools?

Maps, a field journal, a compass , a rock hammer, and other tools

The rock limestone metamorphoses into.........

Marble

What is an example of an example of a common non-foliated rock?

Marble

Limestone is formed from when

Marine organisms make their shells out of dissolved minerals on the ocean floor and then when these organisms decompose, their shells settle onto the ocean floor and that sediment is compacted and cemented (fossils are then also found)

Foliated Rocks

Metamorphic rocks that contain parallel layers of flat and elongated minerals

What are three landforms that are made of rocks?

Mountains, valleys, and sea floors

Are all biochemical rocks carbonates?

No

Do metamorphic rocks crystallize from magma?

No

Do metamorphic rocks form as a result of erosion and deposition?

No

True or False: rocks bend or fold by MELTING

No, WITHOUT MELTING

Was the rock breccia transported very far?

No, the contrary, not much at all

What is an example of volcanic glass?

Obsidian

What are common minerals that cement sediment together?

Quartz, calcite, and clay

What are some important rock forming minerals and their texture?

REFER TO NOTEBOOK

What is the rock cycle?

REFER TO NOTEBOOK

What are some examples of where sedimentary rocks can form?

Rivers and river banks, streams, deserts, valleys, beaches, and backyards

What is an example of a chemical rock and it's composition?

Rock salt - made up mainly of halite

What are some examples of common chemical rocks?

Rock salt, rock gypsum, and limestone

Metamorphic rocks form from when............

Rocks are exposed to extreme heat and pressure or the addition of chemical fluids

Since magma within the Earth is insulated by solid rock it cools (slower or faster) than extrusive rock

Slower

Well rounded rock fragments imply that .....................

Strong forces such as water or ice carved individual clasts and produced smooth surfaces

What are some examples of places where igneous rocks can form?

Subduction zones, mid ocean ridges, and hot spots where volcanos are common

Geologists study rocks by identifying what two things?

Texture and composition

What are the two most important observation factors scientists use to classify rocks?

Texture and composition

Which natural structures in the world are associated with regional metamorphism?

The Himalayas in Asia and the Appalachian Mountains in U.S.A?

Clasts

The broken pieces and fragments

The texture of a rock can be used to determine............

The environment in which the rock formed

Texture

The grain size and the way grains fit together in a rock

Changes in pressure equals what change in minerals?

The minerals align to form layers

The composition of a rock is............

The minerals or grains present in a rock

Which is the rock that changes during metamorphism

The parent rock

What does the term "metamorphosed mean"

The rock has changed in structure and composition

What does the layering in rocks result from?

The uneven distribution of pressure in metamorphism

Carbonate rocks have what reaction when they come into contact with hydrochloric acid?

They fizz

TRUE OR FALSE: Forces on Earth and deep within the Earth drive the rock cycle

True

TRUE OR FALSE? : The minerals in a rock's composition and the arrangement of the the individual grains change in metamorphic rocks

True

True or False? : Water and air can change the physical or chemical properties of rock.

True

TRUE OR FALSE: rocks are changing all the time. If true, why?

True, because of weathering erosion, deposition, compactions, and cementation

Plastic deformation occurs during...............

Uplift events when tectonic plates collide and form mountains

Because of what factors are some rocks that were once deep underground now exposed on Earth's surface ?

Wind, rain, and other factors

What are some forces that cause rocks to break down?

Wind, running water, ice and gravity

Is foliation common in rocks?

Yes

Is the rock cycle natural?

Yes

Will all loose sediment eventually one day turn into sedimentary rock?

Yes

Is the change that forms metamorphic rocks is intense? If so, how do the grains look different?

Yes, the grains can appear in bent or twisted layers

_____________ sediment layers bury ___________ sediment layers

Younger, older

Rock

a natural, solid mixture of minerals or grains

Cementation

a process in which minerals dissolved in water crystallize between sediment grains.

Compaction

a process in which the weight from the layers of sediment forces out fluids and decreases the space between sediment grains

Metamorphism

any process that affects the structure or composition of a rock in a solid state as a result of changes in temperature, pressure, or the addition of chemical fluids

Darker colored minerals are similar to what rock in composition?

basalt

What is an example of a biochemical sedimentary rock?

coal: composed from the remains of prehistoric plants and animals. Over time, those organic remains were buried. The burial of those remain lead to compression, which eventually changed the remain into sedimentary rock.

As magma moves toward the surface, pressure _______________ and the gases ______________ from the molten mixture. This is similar to when CO2 escapes from a carbonated beverage.

decreases, separate

Where do most metamorphic rocks form?

deep within Earth's crust

Magma stored underground can contain

dissolved gases

Uplift is a tectonic process that......

forces rocks onto Earth's surface

Chemical Rock

form when minerals crystallize directly from water

regional metamorphism

formation of metamorphic rock bodies that are hundreds of square kilometers in size: Can create entire mountain ranges!

Grains

fragments that make up a rock

Lighter colored minerals are similar to what rock in composition?

granite

Like igneous rocks sedimentary rocks are classified according to.........

how they form

What are the three major rock groups?

igneous, sedimentary, metamorphic

To determine the type of igneous rock that forms, scientists use what characteristics?

magma composition, the location where the lava or magma cools and crystallizes, and the cooling rate of the lava or magma

Darker colored minerals such as olivine and pyroxene contain more of what elements?

magnesium and iron

Nonfoliated Rocks

metamorphic rocks that have mineral grains with a random, interlocking texture

What is contact metamorphism?

metamorphism due to contact with or proximity to an igneous intrusion.

Magma

molten or liquid rock underground

Lava

molten rock that erupts on Earth's surface

Plastic Deformation

permanent change in shape by bending and folding

Some microscopic organisms make their shells by........ & what rock do their shells turn into after the organisms decompose?

removing silicon and oxygen from seawater. When the organisms decompose, the processes compaction and cementation turns their shells into rock chert

What are the building blocks of sedimentary rocks?

rock fragments, mineral crystals or the remains of certain plants and animals

Sediment

rock material that forms where rocks are broken down into smaller pieces or dissolved in water as rocks erode

Volcanic Glass

rock that forms when lava cools too quickly to form crystals

Clastic Rock

sedimentary rock that is made up of broken pieces of minerals and rock fragments

Sedimentary rocks form when or from

sediments and rock fragments go through the processes of compaction and cementation, evaporation of water & organic remains

Igneous rocks are classified, in part, based on their ___________ content

silica

Light colored minerals such as quartz and feldspar contain more of what mineral?

silica

Sedimentary rocks form where............

the sediment is deposited

Rock Cycle

the series of processes that change one type of rock into another type of rock

contact metamorphism

when magma comes in contact with existing rock, and its thermal energy and gases interact with the surrounding rock, forming new metamorphic rock