Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
22 Cards in this Set
- Front
- Back
How is grain size connected to sedimentary rock name?
|
Sed rocks are named after the diameter of the rocks, increasing size to decreasing size. conglomerate/ Breccia, sandstone, mudstone
|
|
What is the difference between a conglomerate and a breccia?
|
Conglomerate has rounded clasts while Breccia has angular clasts.
|
|
What is the volume fraction of gravel in a conglomerate?
|
30% gravel
|
|
What is the fraction of mud in an arenite?
|
<15% I think
|
|
What is the grain size associated with an arenite?
|
<.03mm
|
|
What is a Wacke?
|
wackes are poorly sorted sand stones
|
|
What the definition of a Mudstone?
|
Mudstone is less than 30% gravel, at least a 1:1 sand ratio.
|
|
What are the definitions for Lithic Arenite, Feldspathic Arenite, Quartz Arenite, Arkose, Lithic Arkose, Feldspathic Litharenite, Litharenite, and Subarkose?
|
JUST BE ABLE TO RECREATE THE TRIANGLE. The first three are composed of lithic grains with increasing sorting and quartz content. Arkose:
|
|
Why is a compositional classification for sandstones useful?
|
Helps us predict the diagenetic process a sandstone might undergo. also directly indicates the compositional maturity of the sediment grains
|
|
What is the phi scale?
|
2 to the power of -phi
|
|
What are the basic size classes in the Wentworth Scale? What is the mm size break for each of these?
|
Gravel, Sand Mud. Gravel<2mm=sandstone<.0625mm=mud
|
|
What minerals can occur as clay-sized grains?
|
less than .0039mm
|
|
What is mud? Mudstone? Silt? Siltstone? Clay? Claystone? Shale? What does fissile mean?
|
mud is a type of sediment with a grain size of less than .0625mm. mudstone is a rock name with mud sediment, clay is a subgroup of mud that is the sediment of claystone and shale. silt is a subgroup of mud, larger than .0039mm, sediment in siltstone
|
|
How do clay minerals form? Why are they so common?
|
product of weatheared, primarily Feldspars, but also mica pyroxene, amphibole etc.
|
|
What is the basic mineralogic description of clay?
|
primarily Feldspars, but also mica, pyroxene, amphibole. parallel sheets of Si22O5
|
|
What is the role of surface area in clay mineralogy?
|
A lot of area for chemical reactions
|
|
How stable are clay minerals?
|
very stable
|
|
Why are clay-rich deposits common hydrocarbon source rocks?
|
organic material adheres to clay
|
|
For the Kaolin Clay Group, what is the most common mineral? What is its basic formula? What is a laterite? How is kaolinite formed? What are some uses of this mineral?
|
silicates, Al2Si2O5(OH)4. common weathering product of highly leached tropical soils (laterite). Used in porcelain, medicine, coated paper, toothpaste, food additive, cosmetics.
|
|
For the Illite Clay Group, what are the most common minerals? What is its basic formula? What minerals weather to Illite? What does the presence of Glauconite mean?
|
Iron-rich member,
(K,H3O)(Al,Mg,Fe)2(Si, Al)4O10[(OH)2(H2O)] weathers from feldspar, and muscoovite. used in ceramics with some industrial use. |
|
For the Chlorite Clay Group, what is the basic formula? What minerals weather to Chlorite?
|
Pyroxene, Amphibole, & Biotite weather into chlorites,
Clinochlor (Mg-rich), Chamosite (Fe-rich), Nimite (N-rich), Pennantite (Mn-rich) |
|
For the Smectitie Clay Group, what are the most common minerals? What is the basic structure? Why are these clays referred to as “swelling clays”.
|
Weathers from volcanic rock, bentonite from volcanic ash. Expanding clay used in drilling mud, landfill liners, well/pond plugs.
|