chapter 3 Flashcards
Three Types of Rocks
Igneous Rocks
Sedimentary Rocks
Metamorphic Rocks
Formed by cooling and solidification of magma
Igneous Rocks
Igneous came from the Latin word ________ which means fire
ignis
Two Major Types of Igneous Rocks
Intrusive Rocks
Extrusive Rocks
Type of igneous rock that are at the crust surface
Extrusive Rocks
Type of igneous rocks that are beneath the earth’s surface
Intrusive Rocks
Two Groups of Intrusive Rocks
Plutonic Rocks
Hypabyssal Rocks
These are rocks that crystallize at great depths
Plutonic Rocks
These are formed when magma solidifies close to the earth surface
Hypabyssal Rocks
General Properties of Igneous Rocks
- They all contain minerals.
- The majority are made up of silicate materials.
- The process of igneous rock formation cannot be directly observed.
- They can be fine-grained or coarse-grained.
- Lava that cools quickly often has a glassy texture.
Igneous Rocks Textures
Aphanitic
Glassy
Phaneritic
Porphyritic
describes the texture of fine-grained igneous rock
Aphanitic
texture that is similar to broken glass
Glassy
texture in which mineral grains are large enough to be seen with the unaided eye
Phaneritic
texture of large crystals in a fine-grained matrix
Porphyritic
Classification of Igneous Rocks
Felsic Igneous Rock
Intermediate Igneous Rock
Mafic Igneous Rock
Ultramafic Igneous Rock
This is an igneous rock, so it is commonly found underground near volcanoes and it can occur as border rocks around granitic and other plutons. It can also be found in the oceanic crust, especially near mid-ocean ridges and ancient mountains that were formed from compressed and uplifted oceanic crust.
Gabbro
Properties of Gabbro
- dense mafic rock
- dark grey to black in color
- has a medium to coarse grained texture
silica content of gabbro
45–52%
This is an igneous rock characterized by the large crystals that it contains which can be meters long, and its variable texture. It forms at the end of the stage of a magma’s crystallization when water separates from magma pockets along the margins of batholiths where it is often found. It yields useful dimension stones and stone aggregates for the construction industry.
Pegmatite
Properties of Pegmatite
- plutonic rock, of variable texture and coarseness
- yellowish-white rock
Pegmatite is mainly composed of three minerals:
quartz, orthoclase (K-feldspar), and albite (Na-feldspar)
This is a dark-colored igneous rock that occurs in dikes, sills, and other shallow intrusions in the Earth’s crust. It is also known as diabase in North America. It is commonly found in regions of tectonic extension.
Dolerite
This is chemically and mineralogically similar to gabbro so it is also called “microgabbro”, but with significantly smaller crystal grains, essentially making it a “fine-grained” version of gabbro.
Dolerite
This is an igneous rock and it’s the most common volcanic rock on Earth. It is also present on the Moon, Mars, Venus, and Mercury.
Basalt
Properties of Basalt
- light grey to black in color
- basalt fibers can be mixed with concrete to improve its cracking energy absorption
Basalt is rich in _______ and __________ and is mainly formed of olivine, pyroxene, and plagioclase.
iron, magnesium
A hard and tough rock with an average density between 2.65 and 2.75 g/cm. It is found in abundance in all continents as part of the continental crust. It is a type of igneous rock that is strong and durable. It is composed of quartz, feldspar, and mica, and is often used for countertops, flooring, and other decorative purposes.
Granite
Average density of granite
between 2.65 and 2.75 g/cm
Granite is rich in _______; therefore it is very much resistant to decay.
silica
Other minerals that may be present in a piece of granite include ________ and __________.
amphibole
muscovite
Granite are primarily formed from ____________.
continental crust.
It forms from the slow crystallization of magma below Earth’s surface.
Granite
This is a coarse- grained intrusive igneous rock with a general composition similar to that of granite, but deficient in quartz.
Syenite
This is the major mineral component of syenite, total feldspar content is > 65% and quartz is typically lacking.
Alkali feldspar
Syenite generally forms in __________________, or in _______________.
thick continental crustal areas
Cordilleran subduction zones
This is a relatively rare rock that is gray or dark- gray in color, with coarse grains.
Diorite
The mineral composition of diorite is primarily composed of ______________ and ___________.
plagioclase feldspars and amphibole
Smaller amounts of _________, _________, and _________ may also be found in diorite
pyroxene, biotite, and quartz
Diorite is produced in __________, and in _________ where it can occur in large volumes as batholiths in the roots of mountains.
volcanic arcs
mountain building
These are rocks made of lithified sediments
Sedimentary Rocks
These rocks also form in deposits of pre-existing rocks or pieces of once-living organisms that accumulate on the earth’s surface.
Sedimentary Rocks
It often have distinctive layering of bedding.
Sedimentary Rocks
Are loose, solid particles originating from:
- Weathering and erosion of pre-existing rocks
- Chemical precipitation from solution including secretion by organisms in water
Sediments
Types of Sedimentary Rocks
Clastic Sedimentary Rock
Chemical Sedimentary Rock
Organic Sedimentary Rock
it is formed from broken rocks fragments weathered and eroded by river, glacier, wind, and sea waves
Clastic Sedimentary Rock
rocks fragments include __________, ________, and ___________
pebble, sand silt, and clay
It usually formed in water environment such as river, lakes, ocean but can also form in deserts.
Clastic Sedimentary Rock
Formed when the water components evaporated, leaving dissolved minerals behind. It is very common in arid lands such as the deposits of salts and gypsum.
Chemical Sedimentary Rock
Formed from the accumulation of any animals or plants debris such as shells and bones.
Organic Sedimentary Rock
Plants and animals debris have _______ minerals in them that pile on the sea floor over time to form organic sedimentary rock.
calcium
Forms in marine environments due to accumulation of coral, shell fragments, and calcite precipitation.
Limestone
Limestone are found in _________, ___________, and __________.
sedimentary basins, continental shelves, and reefs
Major deposits of limestone are in _______, _________, and __________.
Europe, North America, and Asia
Often forms at the base of mountain ranges and near ancient river systems.
Sandstone
Sandstone are found in ___________, __________, and _____________.
fluvial (river), alluvial fan, and glacial deposits
Common in lake beds, floodplains, and deep marine environments
Conglomerate
Conglomerate are found in ______________ worldwide.
sedimentary basins
Forms in fault zones, landslides, volcanic eruptions, and impact craters
Breccia
Breccia are found in ______________ regions.
tectonically active
Common in river deltas, deserts, beaches, and shallow marine environments
Shale Rocks
Shale rocks are found in _____________ and _____________.
sedimentary basins and ancient riverbeds
Limestone is a sedimentary rock, generally _______ in color, and forms from the remains of once-living things at the bottom of the oceans.
white
_____________ generally contains shells or bones of animals or remains of plants.
Limestone
The remains of plants or animals from a long time ago are called _________.
fossils
This is formed when sand is glued (cemented) together.
Sandstone
Sandstone is mostly made up of ________.
quartz
Sandstone when formed in ________ may have a layer that looks like ripples or waves.
water
These rocks form from larger rocks, made up of round pebbles, stones, or even boulders that are carried by fast-moving water.
Conglomerate
The word Conglomerate originates from a Latin word that means ____________.
lumped together
Rocks mix with sand and are bound together by ____________.
natural cement
This rock is a clastic sedimentary rock made up of broken mineral fragments or rocks bonded together by a coarse-grained matrix that can be similar to or different from the composition of fragments.
Breccia
These can vary in color depending on their composition. They can be dark grey, greenish, reddish, and brown or yellowish brown.
Shale Rocks
Because of shales’ ______________, they are relatively smooth.
finely-grained clay minerals
They easily break along thin layers or flat planes to varying degrees.
Shale Rocks
These are formed from the alteration of pre-existing rocks due to heat, pressure, and chemical processes.
Metamorphic rocks
This is the transformation of existing rock to rock with a different mineral composition or texture.
Metamorphism
Classification of Metamorphic Rocks
Foliated Rocks
Non-foliated Rocks
Occurs over large areas due to tectonic forces. It involves both high pressure and temperature.
Foliated Rocks
Foliated rocks create foliated metamorphic rocks such as _______ and _________.
schist and gneiss
Occurs when rocks are subjected to high temperature due to their proximity to molten magma or lava.
Non-foliated rocks
Textures of Metamorphic Rocks
Crystalloblastic
Palimpsest (Relict)
Textures which have developed newly during the process of metamorphism
Crystalloblastic
Two kinds of Crystalloblastic Textures
Xenoblastic
Idioblastic
Textures which belong to parent rocks but still retained in metamorphism rocks
Palimpsest (Relict)
This is a non-foliated metamorphic rock composed almost entirely of quartz.
Quartzite
It is dominated by quartz, and in many cases, the original quartz grains of the sandstone are welded together with additional silica.
Quartzite
Quartzite is ___________________.
metamorphosed sandstone
It forms when a quartz-rich sandstone is altered by the heat, pressure, and chemical activity of metamorphism.
Quartzite
Characteristic and Physical Properties of Quartzite
Texture: Granular
Parent Rock: Sandstone
Hardness: 7 on Mohs scale hardness
Color: Pure quartzite is white but quartzite exists in a wide variety of color.
Other features: Generally gritty to touch.
Porosity: Quartzite has a range of porosities.
This is used for making bricks and other strong building materials.
Quartzite
This can be used as railroad track ballast because is so hard and durable.
Crushed quartzite
It can be used in many different shapes and forms including landscaping, building stone, as a feature wall, tiles or even stone cladding. Some of the most common uses indoors are floors, countertops, vanities, fireplace surrounds, etc.
Quartzite
At least 90% of quartzite rock is _______.
quartz
The purest form of silica found on Earth can be found in __________.
quartzite
The shade of quartzite is dependent upon the amount of ____________.
iron oxide
Quartzite can be found in many countries including ___________, ____________, and ____________.
Canada, the United Kingdom, and the United States
The word “marble” derives from the Ancient Greek _______ , which means ______________.
mármaros
crystalline rock, shining stone
This is a granular metamorphic rock, it is derived from limestone or dolomite and it consists of a mass of interlocking grains of calcite or the mineral dolomite.
Marble
It is formed when limestone buried deep in the older layers of Earth’s crust is subjected to heat and pressure from thick layers of overlying sediments.
Marble
It may also form as a result of contact metamorphism near igneous intrusions.
Marble
Characteristics and Physical Properties of Marble
Color: White, pink
Parent Rock: Limestone
Grain size: medium grained; can see interlocking calcite crystals with the naked eye
Hardness – 3 on Mohs scale of hardness
Rocks Texture: Granoblastic, granular
Marble is a versatile and beautiful natural stone that has been used for centuries in a wide variety of applications:
Building and architecture
Sculpture
Countertops and tabletops
Flooring
Landscaping
Art and crafts
Slate comes from the Old French word _________ which means __________, from the verb slater, to shatter.
scalar
fragment
Is a fine-grained, foliated metamorphic rock this is created via the alteration of shale or mudstone by means of low-grade local metamorphism. It is famous for a extensive form of makes use of such as roofing, floors, and flagging due to its sturdiness and appealing look.
Slate
These are usually formed from mudstone that has been put under pressure and heated up during plate collisions and mountain building.
Slate
Characteristics and Physical Properties of Slate
Parent Rock: Shale, Mudstone, or Siltstone.
Color: Gray slate is common, but occurs in a variety of colors, including brown, purple, green, and blue.
Texture: Foliated Metamorphic Rock
Grain size: Very fine-grained; crystals not visible to the naked eye.
Hardness: Ranges between 2.5-4 on the Mohs scale
Other features : smooth to touch
Slate is mainly used for:
Roofing
Facade cladding Flooring
Decorative aggregate
Other uses: tables, countertops, plates for restaurant
Gneiss originates from the German word ________, meaning ________.
Gneiss
spark
It is a foliated metamorphic rock. It exhibits gneissic banding, characterized by thick foliation bands.
Gneiss
It forms under high-grade regional metamorphic conditions.
Gneiss
It develops from pre-existing igneous or sedimentary rocks.
Gneiss
It develops from the metamorphism of shale, granite, or volcanic rocks.
Gneiss
Characteristics and Physical Properties of Gneiss
Parent Rock: Shale, granite, and volcanic rocks.
Texture: Foliated, with foliation on a scale of centimeters or more.
Grain Size: Medium to coarse-grained; visible to the naked eye.
Hardness: Ranges from 6 to 7 on the Mohs scale.
Color: Alternating lighter and darker sub-parallel discontinuous bands.
Other Features: Generally rough to the touch
It is used as a dimension stone for construction, paving, and curbing projects.
Some types can be polished and used as architectural stone for tiles, wall facings, stair treads, window sills, countertops, and cemetery monuments.
Gneiss
The name “schist” comes from a Greek word meaning “_________.”
to split
It is a foliated medium-grade metamorphic rock.
Schist
It contains well-developed mica minerals, such as biotite, chlorite, and muscovite.
Schist
It has a distinct schistosity texture, which gives it a layered appearance.
Schist
Characteristics and Physical Properties of Schist
Texture: Foliated, with a schistosity texture
Parent Rock: Shale, siltstone, and some sandstones.
Grain Size: Fine to medium-grained; crystals are often visible to the naked eye.
Hardness: Ranges from 4 to 5 on the Mohs scale.
Color: Typically consists of alternating lighter and darker bands, often with a shiny appearance.
Other Features: Smooth to the touch.
Historically used for building houses and walls.
Previously used to create decorative rock walls.
Currently used as a decorative stone and in jewelry-making.
Schist
