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Flashcards in Final Review Deck (38)
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1

Controls on sediment and water transport:

Climate and tectonics

2

Controls on accommodation:

Lake Level, subsidence (tectonics )AKA CLIMATE AND TECTONICS

3

Main difference between lakes and marine:

Basin size, salinity

4

Lake Zonation Vocabulary (Zones) to know:

Pelagial (Limnetic) Zone, Littoral Zone, Sublittoral Zone, Profundal Zone, Photic Zone, Mixed Layer, Aphotic Zone

5

Water column stratification defined by:

Temp, pH, O2

6

Water column stratification vocabulary (zones):

Epilimnion, Metalimnion (thermocline), Hypolimnion

7

Word for permanent stratification:

Meromixis

8

Factors causing permanent stratification:

Permanent thermocline and/or permanent chemocline

9

Density stratification caused by:

temperature, salinity, or both

10

Lakes get water by:

inflow (streams + groundwater) + precipitation

11

Lakes loose water by:

outflow + evaporation

12

Open vs closed lake stability:

open lakes have stable lake levels, closed lakes have unstable lake levels

13

Lake inflow vocabulary (flow types):

Homopycnal, Hypopycnal, Hyperpycnal

14

Result of homopycnal flow in lakes:

Deltas with sand and gravel bars (Gilbert type)

15

Result of hypopycnal flow in lakes:

Suspended sediment plumes

16

Result of hyperpycnal flow in lakes:

Density currents (turbidites) that extend out into basin

17

How are carbonate shorelines classified?

Classified according to geometry (bench vs. ramp) and energy level (high vs low)

18

Three lake types:

Overfilled, underfilled, balance filled

19

Overfilled Lake Facies:

Fluvial-lacustrine facies assocation

20

Underfilled Lake Facies:

Evaporative facies assocation

21

Balance Filled Lake Facies:

Fluctuating-profundal facies association

22

Glacier Vocabulary (zones):

Accumulation Zone and Ablation Zone

23

Define Accumulation Zone

The formation of glacier ice takes place here; net gain of mass (top of slope); mass of ice gained each year is greater than that lost by melting

24

Define Ablation Zone

At lower elevations and under warmer temperatures, glacier ice melts at greater races than it is formed and the glacier loses mass; net loss of mass (bottom of slope)

25

How to characterize differences between cold and warm based glaciers:

location, pressure melting point, movement, erosive capability

26

Location: Cold vs Warm Based Glacier

Cold=high latitude, Warm=warm, moist climates (lower lat)

27

Pressure Melting Point: Cold vs Warm Based Glacier

Cold=below pressure melting point; Warm=ice close to pressure melting point

28

Movement: Cold vs Warm Based Glacier

Cold=move slowly by internal deformation (Creep); Warm=moves rapidly by creep and by sliding over thin films of water at base, refreezing incorporates debris at base

29

Erosional Capability: Cold vs Warm Based Glacier

Cold: Ineffective at bedrock erosion; Warm: high erosional and sediment transport potential

30

Glacier Indicators:

Diamictite, Outsized clasts (interpreted as ice-rafted debris), Rhythmites (interpreted as varves), Gelondonite, Striations, chatter marks

31

What is the biggest different with ice-contact and non-ice contact lakes?

With non-ice contact lakes, there are meltstreams, so you get more stream facies (braided river, rippled sands), etc. whereas with ice contact, you essential just have the subglacial facies and the bottom lake lam silts and clays ; varves characteristic of non-contact

32

Wind as a geologic agent is capable of:

Erosion, transport, deposition

33

Define Yardang:

Erosional, streamlined elongate mounds of consolidated material, strong, unidirectional wind

34

3 Transport mechanisms in wind:

suspension, saltation, creep

35

4 Main Eolian Depositional Environments:

Dunes, interdune (between dunes, sand sheet (fringe of dune), extradune

36

Formation of dune depends on:

sand size, environment, vegetation

37

Four types of dunes (draw each):

Barchan, Transverse, Parabolic, Longitudinal

38

Dune grain fall and grain flow formation:

grain fall is grains falling out of suspension, grain flow forms when saltating and rolling grains land on slip face and unstable accumulation builds up, the accumulation then cascades down to the base, advancing the dune