Midterm 1-Rocks and Mineral Flashcards
Weathering Rinds
Rock shows outer weathered zone with successive “layers”of weathering.
Often in combination with chemical weathering.
Resistance to abrasion or scratching and is determined using the MOHs hardness scale
Hardness
Metamorphic rock formed at Low grade metamorphosed basalt-volcanics
From interaction with ocean water or other
fluids → leading to a green colour
Greenstones
Soil Creep
the slow mass wasting process of soil on a slope, under the influence of gravity
Rocky remnants left over from the early formation of our galaxy
Asteroids
Chemical Weathering
Breaks down rock components &
internal structures of minerals
Very coarse grained rocks, formed in the late stage of granitic magma crystallization
Pegmatitic texture
Large grains, surrounded by a finegrained matrix of other minerals similar to the porphyritic texture in igneous rocks
Porphyroblastic textures
Slump
A slump is a form of mass wasting that occurs when a coherent mass of loosely consolidated materials or a rock layer moves a short distance down a slope. Movement is characterized by sliding along a concave-upward or planar surface.
Spheroidal weathering
Rock corners are eroded more rapidly than sides more surface area at corners leading to circular rocks
How do we classify sedimentary rocks?
Shape-degree of roundness form angular,intermediate, to round
Sorting-Very poorly sorted,moderately sorted, and well sorted
Surface extrustions <100km2 and include xenoliths and chill zones
Stock
Fine grained texture, fast cooling(extrusive), microscopic crystals and vesicles from gas bubbles ex.basalt
Aphanitic
Unconsolidated (loose)
Material
Materials not held in place by an adhesive force, at an angle of 35 degrees or greater the face will begin to break apart
Nebular Hypothesis
Solar nebular gas contracted,cooled, and condensed into dust sized particles that aggregated together via collisions into the formation of protoplanets
Fossils
the traces/remains of prehistoric life preserved in rock
Magma intrusions
Volcanic neck,dike,sill,laccolith
Blocky clumpy lava with a liquid underside
Aa lava
Conglomerate
composed mostly of gravel with
rounded fragments but poorly sorted
deposited by strong, turbulent currents such as floods,rivers,steep streams, and glaciers
Fluids effect on metamorphism
Mainly in reference to water and other volitiles it helps to increase the breakdown of ions and facilitate the formation of new crystals coming from either pores in the strata or liquid containing minerals like clay or mica
Composite volcanoes
Larger classical volcano shape made of layers of lava flow and pyroclastic debris. They have large explosive eruptions and form andesite and daltic rocks
non ferromagnesian minerals, composed of Si,K,Na, and Ca
ex.quarts, feldspar,muscovite mica
Light igneous rock
Breccia
conglomerate with angular
grains and have not travelled very far! They can sometimes be confused for pyroclastic rocks
Ripple marks
small waves of sand that show the direction of the wind
symmetric (oscillation ripples), found in areas where the direction of motion changes
asymmetric (current ripples), found in areas where the direction of motion faces on way
Dissolution weathering
Dissolving minerals by a liquid agent such as water or acid ex. Halite dissolving into water
sand
Rocks which are and-sized sandstone and form the sedimentary rock sandstone
Colour of a mineral in powdered form, helps to differentiate between different forms of the same mineral as the streak is always the same
Streak
Earths layers based on composition
1)Crust 0-40km
2)Mantle 40-2900km
3)Outer core 2900-5200 km
4)Core 5200-6400km
Rock Avalanche
The very rapid downslope flowage of rock fragments, during which the fragments may become further broken or pulverized
Impressions of internal and external
surfaces are imprinted into stone and are filled with minerals
Cast and Mould
a depression created after a volcano partially collapses after releasing the majority of its magma chamber in an explosive eruption. typically >1km
Caldera
Rhylolite
Very viscous lava with high silica content, forming thick bulbous deposits
Stages of Coal formation
1)Accumulation of plant material (swamps)
2)Partial decomposition into
peat
3) Shallow burial forming lignite
4) Deeper burial forming
bituminous coal
5) Higher pressure and temp
forming anthracite
all chemical, physical, & biological changes that occur after deposition, but before metamorphism
Diagenesis
Unloading
exfoliation as sheets of igneous & metamorphic
rocks at the surface due to decrease in confining pressure
Sodium and Calcium feldspar, has thin lines along a cleavage face
Plagioclase feldspar
Metamorphic rocks
Rocks undergo enviromental changes(temp/pressure) in the solid form and change state
Regional:over large region from plates
Contact: small scale due to high temps
Main form of bonding in minerals, involves the transfer of electrons
Ionic bonding
Earths gravity captured a passing planetesimal that became our moon
Capture hypothesis
Aa lava
Blocky clumpy lava with a liquid underside
Largest intrusive body with a surface exposure >100km2 and typically act as mountain cores
Batholitihs
Pyroclastic texture
Similar to sedimentary rock, these are rocks that are ejected during eruptions
Sedimentary cycle
1)Decomposition
2)Erosion
3)Transportation
4)Deposition
5)Compaction
Pahoehoe lava
Ropy textured lava with moving inside, lower in viscosity than Aa
Formed via solidification from a very hot liquid which can be either
Intrusive:Fine grained or glassy
Extrusive:Large crystals
Igneous Rocks
Oxidation weathering
Chemical reaction that causes
loss of electrons ex.oxygen (O) combines with Fe
to form haematite (Fe2O3)
Composed chiefly of calcite (CaCO3)
* formed by marine organisms coral reefs,
coquina (broken shells), & chalk
* Inorganic limestones: travertine and oolitic
limestone
Limestone
Least useful method of determining mineral, describes the wavelength of light reflected off the surface
Colour
Metamorphism along fault zones, high T and high P from friction of sliding plates. Pre‐existing minerals deform by ductile
flow, Can fracture rocks and form fault
breccias…or total pulverisation to
mylonites
Cataclastic metamorphism
Types of chemical weathering
1)Dissolution
2)Oxidation
3)Hydrolysis
Rock cycle
The loop that involves the process by which one rock turns into another
gravel
Rocks that are bigger than 2 mm and form the sedimentary rocks conglomerate or breccia
Tendency for a mineral to break along planes of weak bonds making flat and shiny surfaces
Cleavage
Type of sedimentary rock made of Buried & compacted plant material
Coal
Solid aggregate or mass of minerals
Rock
Valence electrons are free to migrate among atoms allowing for electrical conductivity of mineral
Metallic bonding
Most common. Occurs during
mountain building within cores of
mountains → high T and high P with a strong degree of foliation
Regional metamorphism
Evaporite
water evaporates and dissolved stuff
is deposited
Gneiss
The product of high‐grade metamorphism with a Medium‐ to coarse‐grained banded appearance. Often composed of white or
light‐coloured feldspar‐rich layers with bands of dark ferromagnesian minerals. Formed from granites OR a recrystallised schist
Consolidated Material
Rocks held together by some cohesive force like vegetation or clay that keeps the materials from breaking apart as easily
Fission Hypothesis
Centrifugal force associated with earths spin caused a bulge of material that separated from the earth
Chill zones
Fine grained igneous rocks neat contact with cold country rocks
disintegration resulting from plants (roots) &
animals
Biological activity weathering
repeated freezing & thawing of water in
fractures & cracks leading to splitting of rocks occurs at Mountainous regions
with daily freeze/thaw cycles
Frost wedging
Changes in mineral assemblages due to changes in T and P over a limited range
Metamorphic Facies
Fossil types
Body fossils-preserve evidence of the tissue and hard parts of an organism
Trace fossils – preserve evidence of an organism’s activity (tracks and burrows)
Schist
Medium‐ to coarse‐grained metamorphic rock where platy minerals predominate,
e.g. the micas
Frost wedging
repeated freezing & thawing of water in
fractures & cracks leading to splitting of rocks occurs at Mountainous regions
with daily freeze/thaw cycles
silt & clay-sized particles (mud, clay, silt):
particles are too small to identify by eye
over 1/2 of all sedimentary rocks
deposited in quiet (slow moving) water
* deep ocean & continental slope, lakes, floodplains
Siltstone & Shale
A nonfoliated metamorphic rock that is formed from limestone or dolostone comprised of clacite or dolomite crystals
Marble
Rocks held together by some cohesive force like vegetation or clay that keeps the materials from breaking apart as easily
Consolidated Material
Metallic bonding
Valence electrons are free to migrate among atoms allowing for electrical conductivity of mineral
Specifications to be considered a mineral
1)Naturally occurring
2)solid
3)ordered internal structure
4)Definite chemical composition
5)Usually inorganic
Vent
Opening that is connected to magma chamber via a pipe
Detrital sedimentary rocks
created from weathered and eroded fragments of pre-existing rock that have been transported and cemented together
The reaction of any substance with water ex.Granite (mainly quartz + K feldspar) + carbonic acid (H2O + CO2)forms Kaolinite, Free potassium, and loose quartz
Hydrolysis weathering
Raindrop Marks
impact of raindrops on soft mud and indicates sediment was exposed to the earths surface at one point
Very rapid cooling of molton rock ex. obsidian/pumice
Glassy
Debris / Mud flows
fluid movement of coarser material & rock
in mud matrix
Pre existing rocks are broken down and carried and deposited into new rocks
Sedimentary rocks
Examples of oxides
Hematite
Dissolving minerals by a liquid agent such as water or acid ex. Halite dissolving into water
Dissolution weathering
Very viscous lava with high silica content, forming thick bulbous deposits
Rhylolite
Blocks vs Bombs
Blocks are fragments broken from solid rock, while bombs are molten when ejected
Rock corners are eroded more rapidly than sides more surface area at corners leading to circular rocks
Spheroidal weathering
Trigger mechanisms of slope collapse
Removal of Vegetation, Earthquakes, Liquefaction, Dams,Road cuts
water heated by subsurface magma but run out of the ground instead of erupt
Thermal springs
Colour
Least useful method of determining mineral, describes the wavelength of light reflected off the surface
derived from material carried in solution to lakes/seas and precipitation from solution to form “chemical sediments through organic or inorganic means
Chemical Sedimentary Rocks
Chemical reaction that causes
loss of electrons ex.oxygen (O) combines with Fe
to form haematite (Fe2O3)
Oxidation weathering
Types of mechanical weathering
1)Frost wedging
2)Unloading
3)Thermal expansion
4)Biological activity
Gradation in degree of metamorphism between slate & schist it has a glossy sheen and wavy surfaces and is composed mainly of fine crystals of muscovite and/or chlorite
Phyllite
Holes in rock texture due to trapped gas
Vesicular texture
Dolostone
formed from limestone when Mg
replaces some Ca and is a type of chemical sedimentary rock
Frost line
Transition zone from terrestrial planets and gas giants, The frost line for the Solar System lies between Mars and Jupiter.
Sources of heat on earth
External-Solar radiation
Internal-Radioactive decay
Bowens reaction series
Ultramafic- Peridiot, Komatite, Olivine
Mafic-Pyroxene, Garbbo and Basalt, Calcium feldspar
Intermediate magma-Amphibole and Biotite mica, Diorite and Andesite, Sodium feldspar
Felsic-Quartz,Feldspar,Granite, Rhyolite
Erosion
the geological process in which earthen materials are worn away and transported by natural forces such as wind or water
Dome
form from the slow extrusion of highly-viscous silica lava. These lava’s are too thick to spread out into a lava flow. Most domes are small and many do not have a crater
Mechanical weathering
Physical forces break rock into smaller &
smaller pieces without changing mineral composition
Streak
Colour of a mineral in powdered form, helps to differentiate between different forms of the same mineral as the streak is always the same
Begins at around 100m and at a temp around 300c, a low temp and low pressure environment very little changes although the minerals might change
Burial metamorphism
The moon formed concurrently with the earth from a local cloud of gas and dust
Double planet hypothesis
Course grained texture, Formed from slow cooling (intrusive) with crystals large enough to see without a microscope ex.granite
Phaneritic texture
Marine-Ocean beds
Continental-mountains, lakes, rivers
Transition-beach, deltas
Sedimentary environment types
Broad and slightly dome shaped formed from continuous mild eruptions of large volumes of lava, form basalt and cover large areas
Shield volcanoes
Geological factors that affect weathering
Properties of the parent rock-Some minerals weather more readily than others and Fractured rocks more susceptible to weathering
Rainfall and temperature-Warm,wet climate speeds up chemical reactions
Cold, wet/dry climate favours physical weathering
Length of exposure, longer time exposed more weathering
Two or more minerals with the same chemical composition but different crystalline structures ex.Diamond and graphite
Polymorph
The ferromangesian rocks that contain Fe or Mg, include olivine,pyroxene,amphibole, and biotite mica
Dark igneous rock
A non foliated metamorphic rock formed from quartz‐rich sandstone where the quartz grains are recrystallised & fused together.
Made with Contact & regional metamorphism
Quartzite
Batholitihs
Largest intrusive body with a surface exposure >100km2 and typically act as mountain cores
Basalt
MOst abundant volcanic rock with an 80% Fe Mg composition, heat of 800-1000c
composed of sand grains and is the 2nd most abundant sedimentary rock deposited by moderate currents:
such as rivers & deltas, beaches, wind (sand dunes)
and is mostly composed of quartz
Sandstone
Classifications of mass wasting
1)Material type- Soil or bedrock
2)Motion type, Fall,slide, or flow
3)Rate- Fast or slow
Amphibolite
Medium to high-grade metamorphism
of mafic volcanics with Lots of amphiboles and plagioclase
Rocks that are bigger than 2 mm and form the sedimentary rocks conglomerate or breccia
gravel
Phreatic explosion
team-driven explosions that occur when water beneath the ground or on the surface is heated by magma, lava, hot rocks, or new volcanic deposits
Igneous Rocks
Formed via solidification from a very hot liquid which can be either
Intrusive:Fine grained or glassy
Extrusive:Large crystals
Larger classical volcano shape made of layers of lava flow and pyroclastic debris. They have large explosive eruptions and form andesite and daltic rocks
Composite volcanoes
External expression of the ordered internal arrangement of atoms when there are no limitations to space
Crystal form
Movement of plates apart, ex.Midocean ridges
Divergent plates
Similar to sedimentary rock, these are rocks that are ejected during eruptions
Pyroclastic texture
Difference between quiet and explosive eruptions
Quiet will form mafic to intermediate rocks where as explosive form felsic rocks
addition or substitution of
original material by different mineral ex.petrified wood
Petrifaction / Replacement
Stages of bowens reaction series and examples
Ultramafic, peridiot
Mafic, basalt and gabbro
Intermediate, andesite and diortie
felsic, rhyolite,granite
Quartzite
A non foliated metamorphic rock formed from quartz‐rich sandstone where the quartz grains are recrystallised & fused together.
Made with Contact & regional metamorphism
Graded beds
Normally graded beds generally represent depositional environments which decrease in transport energy (rate of flow) as time passes, but these beds can also form during rapid depositional events. Coarse at the bottom and fine at the top
Example of a independent tetrahedron silicate
Olivine
– Individual tetrahedra
linked together by iron
and magnesium ions
– Forms small, rounded
crystals with no cleavage
Water content and mass wasting
Water increases the weight and decreases the
strength of the material in the slope. Adding pore pressure in the slope increases, and clay minerals become hydrated and expand. As well as dissolving cohesive minerals.
example of a 3d network silicate
Feldspar 3D framework of
tetrahedra exhibit 2
directions of perfect
cleavage at 90 degrees
Ionic bonding
Main form of bonding in minerals, involves the transfer of electrons
Type of minerals associated with different plate interaction zones
Spreading:basalt
Subduction:Felsics
Examples of carbonates
Calcite (calcium carbonate) & Dolomite (calcium magnesium
carbonate) Calcite reacts with acid where as dolomite needs to be powdered
exfoliation as sheets of igneous & metamorphic
rocks at the surface due to decrease in confining pressure
Unloading
Magma
Produced from partial melting of rocks in the crust and upper mantel
Metamorphisim that occurs at relatively low T (200‐320°C) and low P forming Lots of water containing minerals (e.g., clays, serpentine, chlorite)
Low‐grade metamorphism
Burial metamorphism
Begins at around 100m and at a temp around 300c, a low temp and low pressure environment very little changes although the minerals might change
Methods in changing magma composition
1)Magmatic differentiation, separation of melt and earlier formed crystals
2)Assimilation, change in composition via incorporation of foreign material in magma
3)Magma mixing, 2 different magma’s mix together
How to differentiate and oxidizing and reducing enviorment
Deposition in an oxidising environment produces red coloured iron oxides.
Deposition in a reducing(oxygen poor) environment generally results in rocks
having a dark colour
Siltstone & Shale
silt & clay-sized particles (mud, clay, silt):
particles are too small to identify by eye
over 1/2 of all sedimentary rocks
deposited in quiet (slow moving) water
* deep ocean & continental slope, lakes, floodplains
Physical forces break rock into smaller &
smaller pieces without changing mineral composition
Mechanical weathering
Slate
Very fine‐grained metamorphic rock with
excellent rock cleavage and is most often generated from lowgrade metamorphism of shale, mudstone, or siltstone
Example of a sheet silicate
Biotite and Muscovite
Sheet structures that result in one direction of perfect cleavage
– Biotite is the common dark coloured mica mineral
– Muscovite is the common light coloured mica mineral
Produced from partial melting of rocks in the crust and upper mantel
Magma
Low‐grade metamorphism
Metamorphisim that occurs at relatively low T (200‐320°C) and low P forming Lots of water containing minerals (e.g., clays, serpentine, chlorite)
How magma intrudes into surrounding rocks
1)magma invades cracks
2)Magma breaks off rocks and incorporates
3)Magma melts walls of country rock
Metamorphic temperature and pressure route
the breaking down or dissolving of rocks and minerals on Earth’s surface due to either chemical or mechanical factors
Weathering
Centrifugal force associated with earths spin caused a bulge of material that separated from the earth
Fission Hypothesis
created from weathered and eroded fragments of pre-existing rock that have been transported and cemented together
Detrital sedimentary rocks
Theory that the rigid lithosphere moves over a liquid asthenosphere
Plate tectonics
a type of landslide occurring when a mass of rock slides quickly downslope
Rockslides
Factors affecting viscosity of lava
1)Temp:higher temp less viscous
2)Composition-more silica more viscous
3)Dissolved gases-more gas more viscous
water heated by subsurface magma and erupting out of the earth
Geysers
Factors controlling Metamorphism
1)Tempreture
2)Fluid
3)Time
4)Pressure
blocks of rock free fall
from cliffs or mountainsides
Rockfall
Hardness
Resistance to abrasion or scratching and is determined using the MOHs hardness scale
Very fine‐grained metamorphic rock with
excellent rock cleavage and is most often generated from lowgrade metamorphism of shale, mudstone, or siltstone
Slate
Due to the removal of elements by earlier forming crystals the silica components of magma are enriched as crystallization continues
Bowens reaction series
Chemical Sedimentary Rocks
derived from material carried in solution to lakes/seas and precipitation from solution to form “chemical sediments through organic or inorganic means
Bowens reaction series
Due to the removal of elements by earlier forming crystals the silica components of magma are enriched as crystallization continues
Metamorphism at Convergent boundaries
Most metamorphism occurs along convergent plate boundaries where the plate is thickened & heated forming Greenschist, amphibolite, granulite
– Formation of the Earth’s major mountain belts (e.g., Alps,
Himalayas, & Appalachians)
Impact hypothesis
A massive collision with an earth sized object ejected parts of the earths core and mantle into orbit, preferred hypothesis by scientists
Potassium feldspar, lacks fine parallel lines
Orthoclase feldspar
Silicates
Formed from the SiO4^4- aninon arranging into a variety of shapes
Independant tetrahedron
Single chain
Double chain
Sheet
3d network
Cinder cone volcanoes
Small volcanoes built from ejected lava fragments with 30 degree slopes
shows a mixture of grain sizes and results from deposition from melting ice, rockfalls, debris flows,mud flows
Non‐Sorted Sediment
fluid movement of coarser material & rock
in mud matrix
Debris / Mud flows
Example of a sulphate
Gypsum
Geysers
water heated by subsurface magma and erupting out of the earth
Non‐Sorted Sediment
shows a mixture of grain sizes and results from deposition from melting ice, rockfalls, debris flows,mud flows
Occurs due to high T when magma invades host rock, but low P (<10 km depth). A zone of alteration called an aureole forms in the rock surrounding the magma. Produces a fine grained rock with no preferred orientation
Contact metamorphism
a mudflow or debris flow that originates on the slopes of a volcano. Small debris flows are common in the Cascades, where they form during periods of heavy rainfall, rapid snow melt, and by shallow landsliding.
Lahars
Transition zone from terrestrial planets and gas giants, The frost line for the Solar System lies between Mars and Jupiter.
Frost line
Components of Magma
1)Liquid portion (melt) composed of mobile ions
2)Solid portion, typically silicates that have crystallized
3)Volatile gases dissolved into the melt (H2),Co2,SO2)
Rock shows outer weathered zone with successive “layers”of weathering.
Often in combination with chemical weathering.
Weathering Rinds
the geological process in which earthen materials are worn away and transported by natural forces such as wind or water
Erosion
Examples of native elements
Gold,Silver,Copper,Graphite,diamond
foliation
foliation, planar arrangement of structural or textural features in any rock type but particularly that resulting from the alignment of constituent mineral grains of a metamorphic rock of the regional variety along straight or wavy planes.
Cleavage
Tendency for a mineral to break along planes of weak bonds making flat and shiny surfaces
How is the structure of a mineral determined
1)Ion size
2)Ion charge
Debris avalanche
rapid movement of slope
materials (70 km/hr). Steep slopes & rain
Icy solar system body that releases gases as burning up creating its colourful tail
Comet
Examples of Halides
Flourite, Halite,Sylvite
High‐grade metamorphism
Metamorphisim that occurs at relatively high T (>320°C) and high P
Water reliant minerals (muscovite, biotite) lose H2O and nonhydrous minerals are common (pyroxene, garnet)
Biological activity weathering
disintegration resulting from plants (roots) &
animals
Pegmatitic texture
Very coarse grained rocks, formed in the late stage of granitic magma crystallization
Crater
Craters are formed by the outward explosion of rocks and other materials from a volcano. Generally <1km
Rocks which are and-sized sandstone and form the sedimentary rock sandstone
sand
Light igneous rock
non ferromagnesian minerals, composed of Si,K,Na, and Ca
ex.quarts, feldspar,muscovite mica
planar arrangement of structural or textural features in any rock type but particularly that resulting from the alignment of constituent mineral grains of a metamorphic rock of the regional variety along straight or wavy planes.
foliation
Crystal form
External expression of the ordered internal arrangement of atoms when there are no limitations to space
Contact metamorphism
Occurs due to high T when magma invades host rock, but low P (<10 km depth). A zone of alteration called an aureole forms in the rock surrounding the magma. Produces a fine grained rock with no preferred orientation
Rockslides
a type of landslide occurring when a mass of rock slides quickly downslope
Rocks undergo enviromental changes(temp/pressure) in the solid form and change state
Regional:over large region from plates
Contact: small scale due to high temps
Metamorphic rocks
Thermal springs
water heated by subsurface magma but run out of the ground instead of erupt
Removal of Vegetation, Earthquakes, Liquefaction, Dams,Road cuts
Trigger mechanisms of slope collapse
Rockfall
blocks of rock free fall
from cliffs or mountainsides
Hornfels
A non foliated High T contact metamorphism rock made of various minerals.
Coal
Type of sedimentary rock made of Buried & compacted plant material
Dwarf planet
an object in the solar system that orbits the sun and is not a satellite of a planet or celestial body that is nearly spherical in shape
Times effect on metamorphism
Crystallisation, recrystallisation and chemical reactions are VERY SLOW. The longer the time, the bigger the crystals!
Materials not held in place by an adhesive force, at an angle of 35 degrees or greater the face will begin to break apart
Unconsolidated (loose)
Material
8 igneous textures
1)Phaneritic
2)Aphanitic
3)Porphyritic
4)Glassy
5)Pyroclastic
6)Pegmatic
7)Vesicular
8)Amygaloidal
an object in the solar system that orbits the sun and is not a satellite of a planet or celestial body that is nearly spherical in shape
Dwarf planet
The way a mineral reflects light, can be either metallic or non metallic
Luster
Pathways of mineral formation
1)Crystallization from heat
2)Crystallization via precipitation from water
3)Precipitation from vapour
4)Biological activity
5)Change in state
Glassy
Very rapid cooling of molton rock ex. obsidian/pumice
Foliated rock examples
Gneiss, Slate,Schist, phylite
Texture grading of metamorphic rocks
Low grade: Slaty cleavage platy minerals aligned, rock easily split in slabs
Medium grade:Schistosity cleavage,crystals grow larger, scaly appearance
High grade:Gneissic cleavage,ion transfer, mineral segregation, banding
Rock
Solid aggregate or mass of minerals
Cross-bedding
Cross-bedding forms during deposition on the inclined surfaces of bedforms such as ripples and dunes; it indicates that the depositional environment contained a flowing medium (typically water or wind).
Transform plates
Plates that move along side one another ex.San Andreas Fault
Orthoclase feldspar
Potassium feldspar, lacks fine parallel lines
Petrifaction / Replacement
addition or substitution of
original material by different mineral ex.petrified wood
Chert
most formed in ocean, occurs as
layers (beds) & as irregular blobs in
limestone
marine creatures remove silica from
sea water, make shells
Lahars
a mudflow or debris flow that originates on the slopes of a volcano. Small debris flows are common in the Cascades, where they form during periods of heavy rainfall, rapid snow melt, and by shallow landsliding.
Volcanic neck,dike,sill,laccolith
Magma intrusions
Retrograde metamophism
High‐grade rock re‐metamorphosed at lower temperature
very fine-grained rocks and form shale or mudstone
silt, mud, clay
Examples of sulphides
Sphalerite,Galena,chalcopyrite
forms during deposition on the inclined surfaces of bedforms such as ripples and dunes; it indicates that the depositional environment contained a flowing medium (typically water or wind).
Cross-bedding
Terrestrial planets
Rocky particles and metallic compounds form solids in the inner region of our solar system include: Mercury, Venus, Earth, and Mars
Small volcanoes built from ejected lava fragments with 30 degree slopes
Cinder cone volcanoes
A non foliated High T contact metamorphism rock made of various minerals.
Hornfels
Movement of plates together,ex. Mariana trench, Himalayan mountains
Convergent plates
Fine grained igneous rocks neat contact with cold country rocks
Chill zones
Regional metamorphism
Most common. Occurs during
mountain building within cores of
mountains → high T and high P with a strong degree of foliation
Stock
Surface extrustions <100km2 and include xenoliths and chill zones
sheet or stream of soil and rock material saturated with water and flowing downslope under the pull of gravity
Earthflow
Capture hypothesis
Earths gravity captured a passing planetesimal that became our moon
Convergent plates
Movement of plates together,ex. Mariana trench, Himalayan mountains
A massive collision with an earth sized object ejected parts of the earths core and mantle into orbit, preferred hypothesis by scientists
Impact hypothesis
Luster
The way a mineral reflects light, can be either metallic or non metallic
Ropy textured lava with moving inside, lower in viscosity than Aa
Pahoehoe lava
Marble
A nonfoliated metamorphic rock that is formed from limestone or dolostone comprised of clacite or dolomite crystals
formed from limestone when Mg
replaces some Ca and is a type of chemical sedimentary rock
Dolostone
Formed when gas vesicles of vesicular rock are filled in with additional minerals from ground water precipitation
Amygdaloidal texture
7 major classes of minerals
1)Silicates (SiO)
2)Native elements (Au, Ag, C etc.)
3)Oxides (O)
4)Sulfides(S)
5)Sulfates(SO4)
6)Halides (Br,F,Cl)
7)Carbonates (CO3)
Earthflow
sheet or stream of soil and rock material saturated with water and flowing downslope under the pull of gravity
mud shrinkage upon exposure to
air, alternately wet/dry found at shallow lakes, desert basins, flood plains
Mud cracks
Phyllite
Gradation in degree of metamorphism between slate & schist it has a glossy sheen and wavy surfaces and is composed mainly of fine crystals of muscovite and/or chlorite
Double planet hypothesis
The moon formed concurrently with the earth from a local cloud of gas and dust
Chemical sedimentary rocks
form by chemical precipitation that begins when water travelling through rock dissolves some of the minerals and precipitate out through inorganic or organic processes
Example of a double chain silicate
Hornblende Double chain structures involving a variety of ions, Two perfect cleavages exhibiting angles of 124 & 56 degrees
Limestone
Composed chiefly of calcite (CaCO3)
* formed by marine organisms coral reefs,
coquina (broken shells), & chalk
* Inorganic limestones: travertine and oolitic
limestone
Earths layers based on properties
1)Lithosphere- rigid
2)Atenosphere- liquid
3)Mesosphere- rigid
4)outer core- liquid
5)Inner core- rigid
Solifluction
the progressive movement of a mass down a slope caused by freeze-thaw activity. During the warmer months, thaw, water in the soil is stuck by frozen permafrost beneath it, causing solifluction
silt, mud, clay
very fine-grained rocks and form shale or mudstone
conglomerate with angular
grains and have not travelled very far! They can sometimes be confused for pyroclastic rocks
Breccia
Opening that is connected to magma chamber via a pipe
Vent
How are hard animal parts turned into fossils?
Form through one of these pathways
-Essentially unaltered
– Recrystallised
– Petrifaction
– Replacement
– Mould
– Cast
Gas giants
Planets primarily formed of hydrogen and helium alongside metals and rocks Include:Neptune, Uranus, Saturn, and Jupiter.
1)Decomposition
2)Erosion
3)Transportation
4)Deposition
5)Compaction
Sedimentary cycle
small waves of sand that show the direction of the wind
symmetric found in areas where the direction of motion changes
asymmetric , found in areas where the direction of motion faces on way
Ripple marks
Caldera
a depression created after a volcano partially collapses after releasing the majority of its magma chamber in an explosive eruption. typically >1km
Differential weathering
Masses of rock do not weather uniformly due to regional and local factors
Aphanitic
Fine grained texture, fast cooling(extrusive), microscopic crystals and vesicles from gas bubbles ex.basalt
The loop that involves the process by which one rock turns into another
Rock cycle
Pyroclastic flow
a hot (typically >800 °C, or >1,500 °F ), chaotic mixture of rock fragments, gas, and ash that travels rapidly (tens of meters per second) away from a volcanic vent or collapsing flow front
The product of high‐grade metamorphism with a Medium‐ to coarse‐grained banded appearance. Often composed of white or
light‐coloured feldspar‐rich layers with bands of dark ferromagnesian minerals. Formed from granites OR a recrystallised schist
Gneiss
Polymorph
Two or more minerals with the same chemical composition but different crystalline structures ex.Diamond and graphite
a form of mass wasting that occurs when a coherent mass of loosely consolidated materials or a rock layer moves a short distance down a slope. Movement is characterized by sliding along a concave-upward or planar surface.
Slump
MOst abundant volcanic rock with an 80% Fe Mg composition, heat of 800-1000c
Basalt
water evaporates and dissolved stuff
is deposited
Evaporite
Carbonisation
Removal of most organic material,
leaving only a carbon film in the rock
Cataclastic metamorphism
Metamorphism along fault zones, high T and high P from friction of sliding plates. Pre‐existing minerals deform by ductile
flow, Can fracture rocks and form fault
breccias…or total pulverisation to
mylonites
form by chemical precipitation that begins when water travelling through rock dissolves some of the minerals and precipitate out through inorganic or organic processes
Chemical sedimentary rocks
Fracture
Absence of cleavage when a mineral is broken
Cast and Mould
Impressions of internal and external
surfaces are imprinted into stone and are filled with minerals
Planets primarily formed of hydrogen and helium alongside metals and rocks Include:Neptune, Uranus, Saturn, and Jupiter.
Gas giants
Sandstone
composed of sand grains and is the 2nd most abundant sedimentary rock deposited by moderate currents:
such as rivers & deltas, beaches, wind (sand dunes)
and is mostly composed of quartz
Pillowy lava
lavas that contain characteristic pillow-shaped structures that are attributed to the extrusion of the lava underwater, or subaqueous extrusion. Pillow lavas in volcanic rock are characterized by thick sequences of discontinuous pillow-shaped masses
Mud cracks
mud shrinkage upon exposure to
air, alternately wet/dry found at shallow lakes, desert basins, flood plains
Sedimentary rocks
Pre existing rocks are broken down and carried and deposited into new rocks
Plate tectonics
Theory that the rigid lithosphere moves over a liquid asthenosphere
Factors in igneous textures
1)Cooling rates, slow=few but large crystals, fast=many small crystals, very fast=glassy
2)Amount of SiO2 present
3)Amount of dissolved gases
Plagioclase feldspar
Sodium and Calcium feldspar, has thin lines along a cleavage face
composed mostly of gravel with
rounded fragments but poorly sorted
deposited by strong, turbulent currents such as floods,rivers,steep streams, and glaciers
Conglomerate
1)Liquid portion (melt) composed of mobile ions
2)Solid portion, typically silicates that have crystallized
3)Volatile gases dissolved into the melt (H2),Co2,SO2)
Components of Magma
Breaks down rock components &
internal structures of minerals
Chemical Weathering
Lithification
unconsolidated sediments
transformed into solid rock by compaction
and cementation (calcite, silica, and iron
oxide)
Resistance of minerals to weathering most to least
Quartz
Muscovite
Potassium feldspar
Biotite and potassium feldspar
Amphibole
Pyroxene and calcium feldspar
Olivine
50% plagioclase and 50% iron magnesium, more viscous lava than basalt
Andesite
Vesicular texture
Holes in rock texture due to trapped gas
Amygdaloidal texture
Formed when gas vesicles of vesicular rock are filled in with additional minerals from ground water precipitation
are formed by the outward explosion of rocks and other materials from a volcano. Generally <1km
Crater
Pressures effect on metamorphism
As depth of burial increases so does pressure, uniform pressure leads to layering remaining in tact where as differential stress will lead to foliation patterns. Increasing pressure increases chance of metamorphisim
Solar nebular gas contracted,cooled, and condensed into dust sized particles that aggregated together via collisions into the formation of protoplanets
Nebular Hypothesis
the movement of rock and soil down slope under the influence of gravity. Rock falls, slumps, and debris flows are all examples of mass wasting.
Mass wasting
most formed in ocean, occurs as
layers (beds) & as irregular blobs in
limestone
marine creatures remove silica from
sea water, make shells
Chert
Most metamorphism occurs along convergent plate boundaries where the plate is thickened & heated forming Greenschist, amphibolite, granulite
– Formation of the Earth’s major mountain belts (e.g., Alps,
Himalayas, & Appalachians)
Metamorphism at Convergent boundaries
Differentiation
The surface of earth was heated due to meteor impacts causing the earth to melt and then stratify based on density of minerals around 4.6 billion years ago
Metamorphism
The transition of one rock into another by temperatures, pressures
and/or chemical conditions unlike those in which it formed.
Shield volcanoes
Broad and slightly dome shaped formed from continuous mild eruptions of large volumes of lava, form basalt and cover large areas
Medium‐ to coarse‐grained metamorphic rock where platy minerals predominate,
e.g. the micas
Schist
The transition of one rock into another by temperatures, pressures
and/or chemical conditions unlike those in which it formed.
Metamorphism
Thermal expansion
alternate expansion/contraction due to
heating/cooling
Fragments of country rock
Xenoliths
The surface of earth was heated due to meteor impacts causing the earth to melt and then stratify based on density of minerals around 4.6 billion years ago
Differentiation
Divergent plates
Movement of plates apart, ex.Midocean ridges
Porphyroblastic textures
Large grains, called porphyroblasts, surrounded by a finegrained matrix of other minerals similar to the porphyritic texture in igneous rocks
metamorphism in Subduction zones
Mountainous terrains along subduction zones exhibit distinct linear belts of
metamorphic rocks
* High-P, low-T zones nearest the trench->blueschist
* High-T, low-P zones further inland in the region of igneous activity
* High-P, high-T zones at depth in thickened continental crust
Non foliated rock examples
Quartzite, marble, hornfel, Greenstone, amphibolite
Xenoliths
Fragments of country rock
Diagenesis
all chemical, physical, & biological changes that occur after deposition, but before metamorphism
Minerals forming at different temperatures and rates. The large crystals(phenocrysts) are embedded into a matrix of smaller crystals (ground mass) ex.porphyry
Porphyritic
form from the slow extrusion of highly-viscous silica lava. These lava’s are too thick to spread out into a lava flow. Most domes are small and many do not have a crater
Dome
Sedimentary Facies
Different sediments often accumulate adjacent to one another at the same time with each facie having a different property sandstone->shale->limestone
The very rapid downslope flowage of rock fragments, during which the fragments may become further broken or pulverized
Rock Avalanche
Dark igneous rock
The ferromangesian rocks that contain Fe or Mg, include olivine,pyroxene,amphibole, and biotite mica
Factors for magma formation
1)Temperature, higher temp more melting
2)Pressure, lower pressure more melting
3)Volatiles, lower melting temps
alternate expansion/contraction due to
heating/cooling
Thermal expansion
Mass wasting
the movement of rock and soil down slope under the influence of gravity. Rock falls, slumps, and debris flows are all examples of mass wasting.
High‐grade rock re‐metamorphosed at lower temperature
Retrograde metamophism
Hydrothermal metamorphism
Chemical alteration caused when hot, ion‐rich fluids (hydrothermal solutions) circulate through fissures and cracks that develop in rock, occurs along the mid ocean ridge
Sedimentary environment types
Marine-Ocean beds
Continental-mountains, lakes, rivers
Transition-beach, deltas
Asteroids
Rocky remnants left over from the early formation of our galaxy
Absence of cleavage when a mineral is broken
Fracture
Medium to high-grade metamorphism
of mafic volcanics with Lots of amphiboles and plagioclase
Amphibolite
Greenstones
Metamorphic rock formed at Low grade metamorphosed basalt-volcanics
From interaction with ocean water or other
fluids → leading to a green colour
Pyroclastic deposit types
1)Ash and dust- Fine glass fragments
2)Pumice- porus rock from frothy lava
3)Cinders- peas sized
4)Lapilli- walnut sized
the progressive movement of a mass down a slope caused by freeze-thaw activity. During the warmer months, thaw, water in the soil is stuck by frozen permafrost beneath it, causing solifluction
Solifluction
Specific gravity
Ratio of the weight of a mineral to the equal volume of water, or just how heavy that bad boy is.
3 main factors in mass wasting
1)Nature of slope
2)Amount of water
3)Steepness & instability of slope
Andesite
50% plagioclase and 50% iron magnesium, more viscous lava than basalt
Metamorphisim that occurs at relatively high T (>320°C) and high P
Water reliant minerals (muscovite, biotite) lose H2O and nonhydrous minerals are common (pyroxene, garnet)
High‐grade metamorphism
Chemical alteration caused when hot, ion‐rich fluids (hydrothermal solutions) circulate through fissures and cracks that develop in rock, occurs along the mid ocean ridge
Hydrothermal metamorphism
Ratio of the weight of a mineral to the equal volume of water, or just how heavy that bad boy is.
Specific gravity
Phaneritic texture
Course grained texture, Formed from slow cooling (intrusive) with crystals large enough to see without a microscope ex.granite
Comet
Icy solar system body that releases gases as burning up creating its colourful tail
Plates that move along side one another ex.San Andreas Fault
Transform plates
Porphyritic
Minerals forming at different temperatures and rates. The large crystals(phenocrysts) are embedded into a matrix of smaller crystals (ground mass) ex.porphyry
the traces/remains of prehistoric life preserved in rock
Fossils
Removal of most organic material,
leaving only a carbon film in the rock
Carbonisation
Metamorphic Facies
Changes in mineral assemblages due to changes in T and P over a limited range
Hydrolysis weathering
The reaction of any substance with water ex.Granite (mainly quartz + K feldspar) + carbonic acid (H2O + CO2)forms Kaolinite, Free potassium, and loose quartz
Temperatures effect on metamorphism
Has the most effect on metamorphic rock formation as higher heat favours metamoprhisim, this can be due to either igneous heat intrusions or the change in geothermal gradient as crust depth increases
Example of a single chain silicate
Augite,Single chain structures
involving iron and magnesium
Two distinctive cleavages
at nearly 90 degrees
unconsolidated sediments
transformed into solid rock by compaction
and cementation (calcite, silica, and iron
oxide)
Lithification
a hot (typically >800 °C, or >1,500 °F ), chaotic mixture of rock fragments, gas, and ash that travels rapidly (tens of meters per second) away from a volcanic vent or collapsing flow front
Pyroclastic flow
team-driven explosions that occur when water beneath the ground or on the surface is heated by magma, lava, hot rocks, or new volcanic deposits
Phreatic explosion
Weathering
the breaking down or dissolving of rocks and minerals on Earth’s surface due to either chemical or mechanical factors
Masses of rock do not weather uniformly due to regional and local factors
Differential weathering
