rocks Flashcards
Marine environment
shallow and deep
Transitional/sedimentary environment
delta, beach, wave-cut platforms, longshore currents, spit, tombolo
Alluvial environments
alluvial fans, bajada
lacustrine environments
lake
fluvial environment
river, meandering streams, braided streams, drainage patterns
aeolian environment
desert (arid), steppe (semiarid), desert pavement, ventifacts, yardanga, dunes
- Marine Environment
a. Shallow
– continental * (reef environment)
carbonate content
* – buildup structures of carbonate secreting organisms- *– reef is attached with an island
- *– reef (lagoon/body of water) island
- *– circle of coral reef surrounding a lagoon (no island)
shelf Coral reefs Fringing Barrier Atoll
- Marine Environment
a. *
– continental shelf (reef environment)
*carbonate content
*Coral reefs – buildup * of * secreting organisms- Fringing – reef is * with an *
- Barrier – reef — island
- Atoll – * of coral reef surrounding a * (no *)
Shallow
structures , carbonate
attached, island
(lagoon/body of water)
circle, lagoon
island
b. Deep
- Continental * (sedimentation is low); high relief – sediments tend to go to continental rise/abyssal plain to become * (more on * deposit)
- Continental * (deposit as an effect of submarine landslides); may be cut by submarine canyons; characteristic of Bouma sequence
- Abyssal plains ( ) – *: fine-grained sedimentary rocks rich in silica, volcanic materials from mid-oceanic ridge
slope
stable, fine-grained
rise, turbiditic
ocean floor
cherts
- : streams that flow on complexly-networked shallow depth diverging and converging channel
- : coarse material (sand and gravel) with a highly variable discharge
- – response of the drainage system to the type of material and structures (folds, faults, and fractures present in an area)
Braided streams
Stream’s load
Drainage patterns
Aeolian Environment
1. * (arid), * (semiarid)
Blowout - Aeolian erosion
* : rainshadow effect (blocks moisture) no precipitation, dry
2. * (due to deflation)
3. *– polished rocks
4. *– elongated; parallel to direction of wind current (abrasion and erosion)
desert, steppe
Mountain
Desert pavement
Ventifacts
Yardanga
Deposition:
Dunes: * and * where sand is deposited as wind slows down
* – leeward side; * – stoss side
*migrating towards the direction of the * –> cross beds
Glacial (Glacier}Erosion), plucking *glaciers are melting; abrasion (scratch rocks)
Rocks: Till, stratified drift, moraives
mounds, ridges
Deposition, erosion
wind
Deposition:
* : mounds and ridges where sand is deposited as wind slows down
Deposition – * side; erosion – * side
*migrating towards the direction of the wind –> cross beds
Glacial (Glacier}Erosion), plucking *glaciers are melting; abrasion (scratch rocks)
Rocks: Till, stratified drift, moraives
Dunes
leeward, stoss
- *: shoreline where you don’t have sediments
- swash (erosion), backswash (deposition)
- *– formed from longshore currents (hindi connected sa island) attached to land at upstream
- *– sand or gravel bar that connects an island with the mainland or another island
Wave-cut platform:
Longshore currents
Spit
Tombolo
Alluvial environments
- *: fan-shaped * that accumulate along steep mountain fronts
- – coalescing *
Alluvial fans, deposits
Bajada, alluvial fan
- environments
1. Alluvial fans: * deposits that accumulate along steep mountain fronts
2. Bajada – *alluvial fan
Alluvial
fan-shaped
coalescing
- environments
1. Lake: *body of standing, * (fresh) water
Lacustrine
landlocked, non-marine
- environment (river)
1. *: river begins
2. *: river ends
3. *: down hill
4. * (small creek or river that runs into a larger one)
5. * (where two streams meet)
6. *(empties into lake or ocean; often forms a delta with extensive wetlands)
Fluvial River head River mouth: River flow Tributary Confluence Mouth
Fluvial environment (*)
- River head: river *
- River mouth: river *
- River flow: down *
- Tributary (small * or river that runs into a *one)
- Confluence (where two streams *)
- Mouth (empties into *or *; often forms a *with extensive wetlands)
river begins ends hill creek, larger meet lake, ocean delta
Meandering streams: streams that move in * on deep and smooth channels while carrying most of their *as suspension
- Eroded portion: *
- Deposition: *
- Natural levels: deposited during *stage
- Backswamp: *portion of river
- Oxbow lake – connected to *
sweeping bends, load meanderscar point bar flood dehydrated meandering river
- : streams that move in sweeping bends on deep and smooth channels while carrying most of their load as *
1. *: meanderscar
2. *: point bar
3. *: deposited during flood stage
4. *: dehydrated portion of river
5. * – connected to meandering river
Meandering streams suspension Eroded portion Deposition Natural levels Backswamp Oxbow lake
Braided streams: * that flow on complexly-networked shallow depth *
Stream’s load: coarse *(sand and gravel) with a highly variable discharge
Drainage patterns – response of the * to the type of * (folds, faults, and fractures present in an area)
streams, diverging and converging channel
material
drainage system, material and structures
Aeolian Environment
1. desert (), steppe ()
Blowout - Aeolian *
Mountain: * (blocks moisture) no precipitation, dry
2. Desert pavement (due to *)
3. Ventifacts – *rocks
4. Yardanga – elongated; parallel to direction of wind current (abrasion and erosion)
arid, semiarid erosion rainshadow effect deflation polished
Aeolian Environment
- (arid), * (semiarid)
* - Aeolian erosion
* : rainshadow effect (blocks moisture) no precipitation, dry
- (arid), * (semiarid)
- (due to deflation)
- *– polished rocks
- *– elongated; parallel to direction of wind current (abrasion and erosion)
desert, steppe
Blowout
Mountain
Desert pavement
Ventifacts
Yardanga
types of sedimentary environments
differentiated using:
- Marine
- Transitional
- Terrestrial
- Physical
- Chemical
- Biological
reef environment and high carbon composition
• Continental Shelf
- composed of carbonate structures formed by carbonate secreting organisms
• Coral Reefs
coral reef that is directly attached or borders the shore of an island or continent
- Fringing Reef
- long narrow coral reef parallel to shore and separated lagoon
- Barrier Reef
- continuous or broken circle of coral reef
- Atoll
turbiditic deposit formed along the continental rise
Bouma Sequence
• *
1. Progradation- sediments *towards the sea
2. Retrogradation- sediments * away from the sea
• *
1. Transgression- *migration of sea level
Carbonate, forms * environment, retrogradation
2. Regression- *migration of sea level
Silicon, forms * marine environment, progradation
Sediment Movement
advance, retreats
Movement of Sea Level
landward
seaward
shallow, deeper
• Sediment Movement 1. *- sediments advance towards the sea 2. *- sediments retreats away from the sea • Movement of Sea Level 1. *- landward migration of sea level *, forms shallow environment, * 2. *- seaward migration of sea level *, forms deeper marine environment, *
Progradation
Retrogradation
Transgression
Regression
Carbonate - retrogradation
Silicon - progradation
– prograding depositional bodies that form at the point where river deposits in a lake or sea
- Similar morphology to an alluvial fan but deposition result from sharp * in velocity as a * enters standing water or ocean
delta
reduction, stream
Kinds of delta
- (birdfoot delta)- large sediment volume
- – linear features parallel to * and perpendicular to *(sand bars)
- *- smoothly arcuate, wave action reworks sediments, much sandier, beach ridges
River Dominated
Tide Dominated tidal flow, shore
Wave Dominated
- River Dominated (* delta)- large * volume
- Tide Dominated – * parallel to tidal flow and perpendicular to shore (*)
- Wave Dominated- smoothly *, wave action reworks , much sandier, e.g.:
birdfoot, sediment
linear features, sand bars
arcuate, sediments
beach ridges
accumulation of sediments found along the landward margin of the ocean
BEACH
– if there is no sedimentation, the rocky surface interactive with waves
Wave-cut platform
movement of waves at an angle
- Swash: erosion
- Backwash: deposition
Longshore transport
long ridge of sand deposited by longshore current and drift, attached to land at upstream end
Spit
a sand or gravel bar that connects an island with the mainland or another island
Tombolo
fan-shaped deposits that accumulate along steep mountain fronts, as mountain stream emerge into relatively flat lowland; a large portion of sediment load is deposited
Alluvial fans
coalesce alluvial fan
Bajada
landlocked body of standing, non-marine water
Lake
*- small creak that runs into a larger one
Tributary
move in sweeping bends on a deep and smooth channel while carrying most of their load as suspension (snake-like river)
Meandering Stream
after merging 2 streams in the inner bend, there is an isolation of the bent part and the river will look linear
Osbow lake
- flow on complexity networked diverging/converging channels, stream’s load- coarse material (sand and gravel) with a highly variable discharge
Braided Stream
drainage system of braided stream
Drainage pattern
Drainage pattern
- (tree-like)
- (develops on isolated volcanic cone)
- (developed on bedrock)
- (developed on areas of alternating weak and resistant bedrocks)
Dendritic
Radial
Rectangular
Trellis
Drainage pattern
- Dendritic (*-like)
- Radial (develops on isolated *)
- Rectangular (developed on *)
- Trellis (developed on areas of alternating *)
tree
volcanic cone
bedrock
weak and resistant bedrocks
(An area having relatively little precipitation due to the effect of a topographic barrier, especially a mountain range, that causes the prevailing winds to lose their moisture on the windward side, causing the leeward side to be dry)
- Rainshadow effect
Aeolian erosion, sediments are transported
Blowout
formed through deflation
Desert pavement
polished rock through Aeolian abrasion/wind erosion
Ventifacts
remaining portion of rock parallel to the wind direction
Yardang
mounds and ridges where sand is deposited as wind slows down
Dunes
– migration, towards the direction of the wind
Cross bed
- leeward side
* - Stoss side
Deposition
erosion
