Reading...
Play button
Play button
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;
98 Cards in this Set
- Front
- Back
|
Clastic
|
composed of particles
|
|
|
Chemical
|
crystallized out of solution (also known as Precipitates)
|
|
|
Organic
|
formed by living organisms or directly from organic matter
|
|
|
Clay
|
so small, its too fine to even "feel"
|
|
|
Silt
|
can't see but can feel the "grit"
|
|
|
Sand
|
sizes from "can see" up to small peas/BB's
|
|
|
Gravel
|
from pebbles, cobbles, to boulders
|
|
|
Sediments
|
solid particles (clasts)
|
|
|
Lithification
|
"to make a ROCK"
- creates texture |
|
|
- Shale
- Fine grained rock |
Mud- silt and clay-size particles: most used!
|
|
|
Siltstone
- Fine grained rock |
silt sized particles, they're gritty!
|
|
|
Claystone
- Fine grained rock |
clay sized particles, they're smooth
|
|
|
Mudstone
- Fine grained rock |
kinda variation of shale with less sorting (I wouldn't use this term)
|
|
|
Lithification
|
-Compaction of clasts
-Cementation of clasts -Crystallization from solutions |
|
|
Compaction of clasts
|
decrease in pore space
|
|
|
In Clastic Sedimentary Rocks
|
Clastic texture
|
|
|
In Chemical Sedimentary Rocks
|
Crystalline texture
|
|
|
Clastic
|
Composed of either fragments, pieces, or clasts
|
|
|
Chemical
|
material that was dissolved and comes out of solution
|
|
|
Organic
|
Material that was the direct result of living organisms
|
|
|
Sedimentary Breccia
(Largest Particles) |
Angular fragments, close to surface
|
|
|
Conglomerate
(Largest Particles) |
Rounded fragments transported farther
|
|
|
Greywacke
|
- Fine grained Matrix
- Usually from turbidity currents |
|
|
Arkose
(sandstone) |
poorly weathered > 25% feldspar
|
|
|
Quartz sandstone
|
maturely weathered
|
|
|
Coral
|
limestone from direct deposit of CaCO3 by organisms
|
|
|
Coal
|
-Develops from plant matter deposited in an anaerobic environment, first peat, then with compression
-Usually more than 90% organic; not composed of true minerals! |
|
|
Chert
|
both from nodules in limestone (true chemical) and organic: bodies of siliceous tests of marine organisms
|
|
|
Evaporites
|
like limestone, from evaporation of marine basins
|
|
|
Rock Gypsum
|
-Calcium sulfate
-Moh's hardness scale of 2 |
|
|
Rock Salt
|
Sodium Chloride, softer than calcite, 3 plains of cleavage at right angles!
|
|
|
Carbonate Rocks
|
these could be clastic or organic as well!
|
|
|
Recrystallization
|
Chemical sedrox often differ from clastic type by texture- not particle-like but crsytalline texture
|
|
|
Dolmite
|
Replaced in ground water solutions or primary- supersaturated warm shallow marine basins
|
|
|
Limestone
|
made of calcite- from sea water or calcite rich solutions from ground water to "fresh" water lakes
|
|
|
Inorganic varieties
|
true chemical sedrox...from solutions
|
|
|
Biochemical varieties
|
from living organism: CORAL
|
|
|
Bioclastic
|
If particles from living shells with transport: may form coquina or fossiliferous limestone
|
|
|
Beds
|
A primary structure
-formed as a "deposit" also called "Strata" -bedding planes |
|
|
Other Primary structures
|
-Cross bedding
-graded bed -mud cracks -ripple marks -fossils |
|
|
Ripple marks
|
Steep slope faces down current and the gentle slope faces up current
|
|
|
Rain drop marks
|
Primary structures may also include
|
|
|
minerals
|
Primary structures do no include
|
|
|
Lithification
|
Secondary Structures form during...
|
|
|
diagenisis
|
Seconday Structures are also called...
|
|
|
Seconday Structures
|
-Nodules
-Concretions -Solution cavaties where fossils may dissolve out by ground water action |
|
|
Formations
|
Group of different sedimentary rocks representative of a particular depositonal environment
|
|
|
geographic locations
|
Formations were named after
|
|
|
formations
|
Distinctive from neighboring rock units
|
|
|
Sedimentary contact
|
Transitional with other deposits
|
|
|
Other contacs
|
Unconformities or gaps in the geologic record/ no translation
|
|
|
top and bottom
|
Horiziontal planes =
|
|
|
Sorting
|
distribution of sizes
|
|
|
poorly sorted
|
a mix of sizes, weakly layered
|
|
|
Good sorting to well sorted
|
uniform in size and well layered
|
|
|
Unsorted
|
no order of layering or size
|
|
|
Shape
|
rounded or angular
|
|
|
Surfaces
|
smooth/polished to "frosted", etched
|
|
|
Source area
|
closeness based on size and angularity of particles
|
|
|
Environment of Deposition
|
the surroundings or conditions from which a sediment is deposited
|
|
|
Transitional
|
-between Continental and Marine
includes: beaches and coasts, lagoons, reefs, mangrove swamps (deltas?) |
|
|
Marine
|
-formed in ocean basins; vary by depth
From continental shelf, continental slope to abyssal depths |
|
|
geographic locations
|
Formations were named after
|
|
|
formations
|
Distinctive from neighboring rock units
|
|
|
Sedimentary contact
|
Transitional with other deposits
|
|
|
Continental
|
usually fresh- water deposits on the continents
includes: deserts, glaciers, streams with lakes and deltas, ground water, mass wasting |
|
|
Beds
|
=strata; seperated by bedding planes at contacts between different rock layers
|
|
|
Laminations/laminae
|
Layers within the horizontal beds that may be a different angles/ inclined as cross beds
|
|
|
horizontally
|
Stratification or layering of sediment
|
|
|
- conformable
- continuous deposit - unconformable (gaps!) |
Contacts between beds may be...
|
|
|
Lakes
|
-fine sediments
-often organic and peaty: may form Coral |
|
|
Glaciers
|
-Unsorted from ice: till
-Sorted from melt water: Outwash (like stream deposits) |
|
|
Deltas
|
coarsening upward deposits
|
|
|
Reef
|
Organic complexes that may be more marine and carbonate rich
|
|
|
Lagoon
|
quiet brackish water- may be organic, rich, peaty, and can result in Coal... but poor quality
|
|
|
Beach, Barrier Island, Dune
|
uniform and well sorted...usually
|
|
|
Transitional
|
Between Continental and Moraine
|
|
|
Common Continental Deposits
|
- Desserts
- Streams - Glacial Environments |
|
|
Deserts
|
evaporate deposits and dune fields
|
|
|
Talus Slope
|
base of cliffs
|
|
|
Alluvial fan
|
related to stream deposits
|
|
|
Streams
|
channel (flow) and flood plain (sheet flow)
|
|
|
Lake
|
a standing body of water
|
|
|
Delta
|
The exstension of a stream into a standing body of water
|
|
|
Glacial environments
|
Poorly sorted from ice (till) to well sorted from melt water (outwash)
|
|
|
source area by wind
|
Loess removed from
|
|
|
interior basins
|
Deserts evaporate deposit in
|
|
|
Evaporates
|
Crystalline and Chemical
|
|
|
Evaporates
|
Halite and Gypsum
|
|
|
Dunes
|
Wind blown sand
- Well sorted, well rounded, and frosted grains |
|
|
high velocity streams
(Conglomerate) |
Gravel to pebbles is...
|
|
|
very large
|
bed load can be
|
|
|
saltation
|
Farther down stream channels favor sand moved by
|
|
|
Sandstone
|
jumps in grains in flow
|
|
|
graded deposits
|
fines upward
|
|
|
Deep Marine to "abyssal" depths
|
-cold ocean depths may have high silica content
-planktonic organisms would build their shells of chert- like material - chert deposits |
|
|
Shallow Marine Shelf- shale to limestone
|
Can include evaporites in dying marine basins: Gypsum to Halite (evaporate from 80 to 90 %: enrichment)
|
|
|
-ocean basins
-in submarine fans from submarine canyons |
Turbidites on steep slopes in...
|
