Chapter II: Rock-Forming Minerals and Rocks Flashcards

1
Q

What traits of minerals determine their physical properties?

A

Hardness is determined by the strength of the chemical bonds.
Density is determined by the weight of its atoms, and to some degree their structure.
Fracture Pattern is determined by the weakness of the crystalline structure.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What conditions produce various kinds of igneous rock?

A

Mafic igneous rocks are denser than felsic rocks due to the high atomic weight of iron atoms. Extrusive rocks are smooth due to their rapid cooling, conversely intrusive rocks are more granular due to their slow cooling.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the ways in which sedimentary rocks form?

A

Clastic sedimentary rocks form when sediments are deposited then compacted by the weight of sediments above them. Next they are cemented by fluids, causing minerals to precipitate and form the rocks.

Chemical Sedimentary rocks form when they are precipitated from water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How do metamorphic rocks form from other rocks?

A

Composition and texture vary depending on degree of heat and pressure. 4 methods of metamorphism; Regional, Contact, Hydrothermal, and Burial.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How does an ion form from an uncharged atom?

A

Ions are formed when an uncharged atom gains or loses an electron(s) in order to form a more stable valence shell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Silicates

A

Most abundant mineral family in Earth’s crust/Mantle. Basic building block of SiO4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Sedimentary Structure

A

Distinct arrangement of grains which reflects the method of deposition.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why do most sediments formed by weathering consist of silicate minerals?

A

Because silicates make up the majority of rocks on earth.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Silliclastic Sedimentary Rocks

A

Consists of silicate grains produced by weathering and erosion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Regional Metamorphism

A

generally within hundreds of kilometers, caused by catastrophic events such as a meteor impact which creates the conditions necessary for metamorphism.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Contact Metamorphism

A

heat from an igneous intrusion bakes surrounding rock

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Hydrothermal Metamorphism

A

hot, watery, fluids percolate through rocks to form metamorphic rocks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Burial Metamorphism

A

Deep burial of rocks produces the conditions necessary for metamorphism (i.e. Coal from plant material)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Ions

A

Retain their identity when dissolved in water. Enables chemical precipitates like salt.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Aragonite

A

Common minerals consisting of calcium carbonate (CaCO3);
Precipitates directly from shallow tropical seas as tiny needle shaped crystals and accumulates into carbonate mud.
Forms younger Limestone because it is unstable.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Calcite

A

Common mineral consisting of calcium carbonate (CaCO3);
Precipitates to form blocky, or tooth shaped crystals. Forms Limestone that can last much longer than Aragonite based Limestone.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Calcite

A

Common mineral consisting of calcium carbonate (CaCO3);
Precipitates to form blocky, or tooth shaped crystals. Forms Limestone that can last much longer than Aragonite based Limestone.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

8 Major Mineral Groups

A

Silicates, Carbonates, Sulfates, Phosphates, Halides, Oxides, Sulfides, Native Elements.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Silicates

A

(SiO4)^-4 tetrahedra are basic units;
Mostly hard, except for mica and clay minerals, glassy/pearly luster;
Dominant mineral group in crust and mantle;

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Carbonates

A

Positive Ions attached to (CO3)^-2;
soft, light colored;
Mostly sedimentary, but also marble (metamorphic);

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Sulfates

A

Positive ions attached to (SO4)^-2;
Soft, light colored, water soluble;
Mostly sedimentary

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Phosphates

A

Positive ions attached to (PO4)^-3;
soft, weakly soluble;
relatively uncommon sedimentary rocks;

23
Q

Halides

A

Positive ions attached to negative ions;
soft, light colored, water soluble;
most rock forming halides are sedimentary;

24
Q

Oxides

A

Metallic ions combined with oxygen;
soft to hard;
mostly sedimentary but many varieties present in crystalline rocks;

25
Q

Sulfides

A

Metallic ions combined with sulfur;
Soft to medium hard, often metallic;
minor role in rock forming, many precipitate;

26
Q

Native Elements

A

Pure forms of elements;
variable physical properties;
forms graphite through metamorphosed organic carbon;

27
Q

Dolomite

A

Similar to Calcite, but calcium ions are replaced with magnesium ions. Special layered crystalline structure. Not secreted by any organism in the form of a skeleton.

28
Q

What allows one element to substitute for another in the crystal of a particular mineral?

A

Elements can substitute for each other if both atoms have a similar charge and size.

29
Q

Dikes vs Sills

A

Sills are plutons which are injected between sedimentary rock while dikes cut upwards between layers of sedimentary or crystalline rock

30
Q

Plutons

A

another word for intrusive rock

31
Q

How does the origin of clay particles differ from the origin of sand particles from the same rock

A

Clay is formed from chemical weathering while sand is formed from physical weathering.

32
Q

Shale formation vs Sandstone formation

A

Shale can only be formed in calm water because clay settles so slowly. Sandstone forms in moving water because sand settles more quickly.

33
Q

Graded beds

A

Formed by swift currents with varying sediment size. Coarser sediment settles more quickly than finer sediments.

34
Q

Ripples

A

equal slopes, formed by the motion of waves

35
Q

Cross-Beddding

A

Uneven slopes, steeper on the backside, side facing away from current. Formed by water or air currents

36
Q

Mud Cracks

A

Formed when mud is deposited in shallow, calm water. Water evaporates leaving mud exposed and further evaporation leaves cracks as the mud dries.

37
Q

Why do evaporites weather so quickly?

A

Due to their solubility in water, evaporites last above the surface for an extended time only in arid climates.

38
Q

Basalt

A

Formed when lava flows slowly out of a fissure rather than a vent

39
Q

Vent

A

Exposure to the surface from which lava forms volcanoes

40
Q

Pillow Basalt

A

Basalt formed under the sea. Rapid cooling gives its surface a hummocky configuration

41
Q

Pumice

A

Frothy lava from a high velocity eruption, glassy and very light (often floats on water)

42
Q

Tuff

A

sedimentary rock formed from volcanic material

43
Q

Gneiss

A

High quality metamorphic rock, crystals resemble igneous rock

44
Q

Schist

A

low to medium grade metamorphic rock, largely grains of platy material including mica

45
Q

Foliation

A

alignment of platy materials caused by pressures applied during metamorphism

46
Q

Slate

A

very low grade metamorphic rock.

47
Q

Bioturbation

A

disturbance of sedimentary bedding by the activity of animals

48
Q

peat

A

leafy and woody plant tissue accumulated in oxygen deprived water, the starting material for coal

49
Q

Oolites

A

sediments or rocks consisting of nearly spherical grains

50
Q

Intraclsts

A

Fragments of preexisting seafloor material that gets ripped up by storms or other sudden events

51
Q

Fecal Pellets

A

sand sized grains found in carbonate mud which have passed through the guts of invertebrate organisms

52
Q

Coal

A

rock formed by stratified plant debris, can be burned because more than 50% organic compounds

53
Q

Clasts

A

fragments of rock produced by destructive processes