Geology Unit 2 - Fisher

Front 1

What is the world's largest lake?

What is the world's oldest lake?

Back 1

Largest: Caspian Sea

Oldest: Baikal

Front 2

What are the six primary ways that lakes form?

Back 2

1. rift valleys; 2. sags of foreland basins & cratons; 3. glacial scouring & damming; 4. wind deflation; 5. volcanic craters; 6. fluvial activity

Front 3

What are the two types of lake systems?

Back 3

Closed (stratification) and Open (circulating & oxidizing)

Front 4

What is the economic importance of lake depostis?

Back 4

Lake deposits provide oil shale and special salts

Front 5

What is an example of a lake that was formed due to major rifting and faulting?

Back 5

East African Lakes

Front 6

What are examples of lakes that were formed due to a major final fill of foreland basin?

Back 6

Caspian & Aral

Front 7

What are examples of lakes that were formed due to continental sags?

Back 7

Victoria, Kenya, Uganda and Eyre

Front 8

What are examples of lakes that were formed due to glacial features, such as moraine damming and/or ice scouring?

Back 8

The Great Lakes

Front 9

What is an example of a lake that was formed due to volcanic activity?

Back 9

Crater Lake

Front 10

What is an example of a lake that was formed due to deflation by wind scour or damming by wind blown sand?

Back 10

Fayum

Front 11

What kind of lakes do fluvial systems make?

Back 11

oxbow lakes, levee lakes, delta & barrier bar entrapments

Front 12

What are characteristics of closed lacustrine systems?

Back 12

stratified, never turned over, presence of varved sediments, colloid-chemical sediments, carbonate & terrigenous basin, presence of thermocline & hypolimnion

Front 13

What are characteristics of open lacustrine systems?

Back 13

circulatory system, presence of turbidites & burrowed muds, graded bedding mroe likely

Front 14

What are some lacustrine facies?

Back 14

presence of freshwater fossils, better sorted than fluvial & periglacial sediments, may (or may not) show upward & inward fining, presence of seasonal varves.

Front 15

What are 3 kinds of oceanic depositional systems?

Back 15

river dominated deltas
wave dominated deltas
tide dominated deltas

Front 16

What is hyperpycnal flow?
A zone of mixing occurs along the outer edge of the flow. As the river water flows beneath the standing water, it erodes the previously deposited bottom sediments. Further out in the basin, the flow eventually deposits the eroded sediments as turbidites.

Back 16

Hyperpycnal flow is produced when the density of the river water entering the basin is greater than the density of the standing water in the ocean basin. This higher density river water will flow below the standing water in the basin because of the difference in density. (cont. on front)

Front 17

What is a homopycnal flow?

Back 17

Homopycnal flow occurs when the density of the river water is equal to the density of the standing water in the basin. This type of flow is associated with rapid mixing throughout the general flow. There is also abrupt deposition of the sediments carried to the basin by the river as the two water sources meet. Usually freshwater to freshwater.

Front 18

What is a hypopycnal flow?

Back 18

Hypopycnal flow is associated with a lower river water density entering a higher density standing water density in the basin. Under these conditions, the river water will flow out over the standing water gradually depositing the suspended clay portion of the sediment load to the prodelta.

Front 19

What are the 4 geometric shapes of deltaic coastlines?

Back 19

low energy ---> high energy of waves and longshore currents: elongate, lobate, cuspate, strandplain

Front 20

Describe delta morphology for tide-wave-fluvial dominated systems.

Back 20

Lobate deltas are weak fluvial dominated and elongate deltas are strong fluvial dominated. Tidal deltas produce sand ridges. Wave dominated deltas produce beach shorelines.

Front 21

What are some characteristics of fluvial-dominated deltas?

Back 21

Fluvial-dominated deltas are either elongate or lobate, fed by straight distributary channels, and have high suspended load. Ex: Mississippi

Front 22

What are some characteristics of wave-dominated deltas?

Back 22

Wave-dominated deltas are generally fed by meandering streams (soometimes braided), and have a mixed load. Their dominated facies consist of wave reworked coastal barriers but with defining CMB preserved. Ex: Nile, Brazos, Rhone

Front 23

What are some characteristics of tide-dominated deltas?

Back 23

Tide-dominated deltas are high tidal bore, linear, dip oriented tidal sand bars, and often have mangroove swamps. Ex: Mekong, Fly, Ganges, Indus

Front 24

How is the bedding of deltas characterized?

Back 24

Deltas tend to coarsen upwards in texture and in grain size.

Front 25

Deltas tend to _____ seaward.

Back 25

Deltas tend to prograde seaward.

Front 26

How do deltas move around?

Back 26

Deltas shift lobes by avulsion.

Front 27

Which deltaic system makes a great reservoir?

Back 27

Wave-dominated deltas

Front 28

What are four kinds of shorezone systems?

Back 28

Barrier Bars/Lagoons; Strandplains; Cheniers; Tidal Flats

Front 29

How are shorezone systems characterized?

Back 29

Shorezone systems are dominantly wave processes, sediments will coarsen upwards, linear sand bodies are parallel to the basin margin (strike oriented), serrated margins are landward, and they are formed by waves & tidal currents.

Front 30

What separates the upper shoreface from the lower shoreface, and what characterizes each shoreface?

Back 30

Breaker bars are the dividing point. The upper shoreface is higher energy since in contains the long-shore current. The lower shoreface is lower energy which gives rise to burrowing animales and turbation.

Front 31

What are the three common beddings found in shorezones?

Back 31

High-energy planar beds (swash zone); Trough cross-bed current ripples (upper shoreface); Hummocky (offshore transition)

Front 32

Which shorezone systems makes excellent oil reservoirs?

Back 32

Strandplain & Cheniers

Front 33

What is the difference between a strandplain and a barrier bar?

Back 33

Barrier bars will have a lagoon on the landward side and strandplains will instead have either land or a mudflat marsh. Otherwise, the processes are the same. Cheniers are also very similar to strandplains, but are mud-rich.

Front 34

BARRIER BARS

Back 34

HAVE LANDWARD LAGOON, WASHOVER FANS, TIDAL DELTAS (PROCESS OF FORMATION)

Front 35

SANDY STRANDPLAINS

Back 35

SIMILAR TO WAVE-DOMINATED DELTA, EXCEPT CMB IS NOT PRESERVED; NO LAGOON ASSOCIATED, ACCRETED DIRECTLY TO COASTAL MAINLAND

Front 36

MUDDY STRANDPLAINS OR CHENIERS

Back 36

ISOLATED, LENTICULAR SANDS SURROUNDED BY MUD FLATS; ACCRETED DIRECTLY TO COASTAL MAINLAND

Front 37

MUD FLATS

Back 37

LITTLE SAND INVOLVED; COMMON IN MODERATE TO HIGH TIDE AREAS; ALGAL FLATS

Front 38

What are four kinds of shelf systems?

Back 38

Wave dominated shelves; Tide dominated shelves; Carbonate shelfs & platforms; Evaporite shelves

Front 39

MOST _____ CONTINENTAL SHELVES ARE RELICT AND ____________, EXCEPT FOR EXTENSIVE BIOLOGICAL REWORKING AND BIOCHEMICAL DIAGENSIS AND OCCASIONAL STORM CURRENTS

Back 39

MOST CLASTIC CONTINENTAL SHELVES ARE RELICT AND NONDEPOSITIONAL, EXCEPT FOR EXTENSIVE BIOLOGICAL REWORKING AND BIOCHEMICAL DIAGENSIS AND OCCASIONAL STORM CURRENTS

Front 40

SLOPES CAN BE FED DIRECTLY AT THE SHELF EDGE BY _________ ____, BUT IT OCCURS MOSTLY BY _______ OF SHELF EDGE DEPOSITS FROM COASTAL SYSTEMS

Back 40

SLOPES CAN BE FED DIRECTLY AT THE SHELF EDGE BY HYPERPYCNAL FLOW, BUT IT OCCURS MOSTLY BY SLUMPING OF SHELF EDGE DEPOSITS FROM COASTAL SYSTEMS

Front 41

IN SLOPE & DEEP WATER SYSTEMS, FLOWS MAY BE AS ________ (TURBID SUSPENSION), ______ FLOWS AND SLUMPS, AND ______ FLOW

Back 41

IN SLOPE & DEEP WATER SYSTEMS, FLOWS MAY BE AS TURBIDITES (TURBID SUSPENSION), DEBRIS FLOWS AND SLUMPS, AND GRAIN FLOW

Front 42

RESULTS FROM ______ AND ______ FLOWS ARE ________ AND ______ OF DIFFERENT SHAPE AND EXTENT DEPENDING ON SEDIMENT CALIBER AND LOAD

Back 42

RESULTS FROM TURBIDITY AND GRAIN FLOWS ARE CHANNELS AND LOBES OF DIFFERENT SHAPE AND EXTENT DEPENDING ON SEDIMENT CALIBER AND LOAD

Front 43

How are continental shelves formed?

Back 43

Continental shelves are formed by previous prograding coastal sediments.

Front 44

What is the average depth and distance of continental shelves?

Back 44

depth < 400 ft
distance 50-200 miles

Front 45

_________ SHELVES ARE BUILT BY ________ COASTAL SEDIMENTS (DELTAS AND STRIKE SYSTEMS)

Back 45

CONTINENTAL SHELVES ARE BUILT BY PROGRADING COASTAL SEDIMENTS (DELTAS AND STRIKE SYSTEMS)

Front 46

UNDER EQUILIBRIUM ________ CONTINENTAL SHELVES ARE MOSTLY ______________ (70% CURRENT SHELF)

Back 46

UNDER EQUILIBRIUM CLASTIC CONTINENTAL SHELVES ARE MOSTLY NONDEPOSITIONAL(70% CURRENT SHELF)

Front 47

_________ ________ ARE SUBJECT TO MARINE EROSION DURING PERIODIC STORMS, BUT MOSTLY THE SITE SHELL LAGS ANIMAL BURROWING AND BIOCHEMICAL DIAGENSIS

Back 47

CONTINENTAL SHELVES ARE SUBJECT TO MARINE EROSION DURING PERIODIC STORMS, BUT MOSTLY THE SITE SHELL LAGS ANIMAL BURROWING AND BIOCHEMICAL DIAGENSIS

Front 48

WHAT IS THE RESULT FROM SLUMPS AND DEBRIS FLOW?

Back 48

THE RESULTS FROM SLUMPS AND DEBRIS FLOW ARE MASS TRANSPORT DEPOSITS

Front 49

COASTAL SEDIMENTS CAN BE SUPPLIED TO THE SLOPE AND BASIN VIA ________ __________.

Back 49

COASTAL SEDIMENTS CAN BE SUPPLIED TO THE SLOPE AND BASIN VIA SUBMARINE CANYONS

Front 50

SUBMARINE FANS ARE EITHER _____ RICH, ____ _____, OR ____ RICH

Back 50

SUBMARINE FANS ARE EITHER SAND RICH, MIXED LOAD, OR MUD RICH

Front 51

____ ____ FANS ARE HIGHLY ELONGATE, DEVELOP PROMINENT LEVEES, AND COMMONLY EXTEND FAR INTO THE BASIN—HIGH EFFICIENTY FLOW

Back 51

MUD RICH FANS ARE HIGHLY ELONGATE, DEVELOP PROMINENT LEVEES, AND COMMONLY EXTEND FAR INTO THE BASIN—HIGH EFFICIENTY FLOW

Front 52

_____ _____ FANS ARE LOBATE, GENERALLY DEPOSITED AT THE TOE OF THE SLOPE ALTHOUGH SOME ARE CARRIED 100S OF MILES INTO THE BASIN

Back 52

SAND RICH FANS ARE LOBATE, GENERALLY DEPOSITED AT THE TOE OF THE SLOPE ALTHOUGH SOME ARE CARRIED 100S OF MILES INTO THE BASIN

Front 53

______ _____ FANS ARE ELONGATE LOBES WITH LEVEES AND COMMONLY MEANDERING STREAMS; THEY EXTEND BASINWARD A DISTANCE INTERMEDIATE OF SAND RICH AND MUD RICH FANS

Back 53

MIXED LOAD FANS ARE ELONGATE LOBES WITH LEVEES AND COMMONLY MEANDERING STREAMS; THEY EXTEND BASINWARD A DISTANCE INTERMEDIATE OF SAND RICH AND MUD RICH FANS

Front 54

_____ AND ______ FLOWS DEPOSITED ON SLOPE OR AT TOE OF SLOPE BUT MAY FORM INTO MASS TRANSPSORT FLOWS AND EXTEND FAR INTO THE BASIN

Back 54

SLUMPS AND DEBRIS FLOWS DEPOSITED ON SLOPE OR AT TOE OF SLOPE BUT MAY FORM INTO MASS TRANSPSORT FLOWS AND EXTEND FAR INTO THE BASIN

Front 55

LARGE OCEAN BOTTOM CURRENTS, CALLED ________ CURRENTS DUE TO CORIOLIS FORCE, REWORK AND ERODE PREVIOUSLY DEPOSITED SLOPE AND BASIN SEDIMENTS, CREATING DEPOSITS CALL _________

Back 55

LARGE OCEAN BOTTOM CURRENTS, CALLED CONTOUR CURRENTS DUE TO CORIOLIS FORCE, REWORK AND ERODE PREVIOUSLY DEPOSITED SLOPE AND BASIN SEDIMENTS, CREATING DEPOSITS CALL CONTOURITES

Front 56

__________ ARE COMMONLY MOUNDED DEPOSITS AND CAN TREND IN ALMOST ANY DIRECTION BUT COMMONLY PARALLEL TO SLOPE

Back 56

COUNTOURITES ARE COMMONLY MOUNDED DEPOSITS AND CAN TREND IN ALMOST ANY DIRECTION BUT COMMONLY PARALLEL TO SLOPE

Front 57

What two major rocks are included in carbonates?

Back 57

Carbonate rocks include limestones and dolostones

Front 58

Define autochthonous?

Back 58

Autochthonous: originating or formed in the place where found

Front 59

_________ and _______ are dominant controls on carbonate accumulation

Back 59

Geotectonics and Climate are dominant controls on carbonate accumulation

Front 60

Geotectonics controls clastic influx and the shape of the surface that carbonates grow upon.

Back 60

_________ controls clastic influx and the shape of the surface that carbonates grow upon.

Front 61

_____ and ________ control what types of organism communities exist, thus what type of carbonate factory develops

Back 61

Climate and oceanography control what types of organism communities exist, thus what type of carbonate factory develops

Front 62

Carbonate sediments are ________, with only minor local transport. Clastic sediments are _______, with major transport.

Back 62

Carbonate sediments are autochthonous, with only minor local transport. Clastic sediments are allochthonous, with major transport.

Front 63

What are the three carbonate factories?

Back 63

Three Carbonate Factories – Tropical, Cool Water, and Mud Mound

Front 64

Define uniformitarianism.

Back 64

The present is the key to the past.

Front 65

Geotectonics – _______ do not develop typically in proximity to major areas of uplifts

Back 65

Geotectonics – carbonates do not develop typically in proximity to major areas of uplifts

Front 66

What happens to a carbonate factory with an influx of clastics?

Back 66

An influx of clastics “dilutes” the carbonate factory. An influx might be an increase of nutrients. However, carbonate-producing organisms like nutrient “deserts."

Front 67

Carbonate Platforms develop best in _____ from ____ influx, which is typically inbetween what two latitudes.

Back 67

Carbonate Platforms develop best in isolation from clastic influx, which is typically inbetween 30N - 30S.

Front 68

What are five requirements for carbonate sedimentation?

Back 68

Warm water; “normal” marine salinities; clear water (function of distance from clastics and low productivity); low nutrient levels; low organic productivity (linked to clear water)

Front 69

How are the bulk of carbonate sediments produced?

Back 69

The Bulk of Carbonate Sediments are Produced by Photosynthizing Autotrophs

Front 70

Describe the platform profiles of the three carbonate factories.

Back 70

Tropical: mostly very shallow water but with a drop off. Cool Water: begins relatively shallow and depth increases with distance from shore. Mud Mound: produces mounds that increase in magnitude with depth.