Geomorphology

Question 1

Define Karst

Answer 1

A term that is applied to the topography of a region which is underlain by limestone, dolomite, gypsum, or other rocks which can be affected by dissolution.

Question 2

What are 4 conditions necessary for the development of karst terrain?

Answer 2

1. a soluble rock (limesstone) at or near the surface
2. A dense rock, highly jointed and thin-bedded.
3. Entrenched valleys below uplands underlain by soluble rock and well-jointed rocks
4. A region of moderate to abundant rainfall

Question 3

Sinkholes: What? Environment?

Answer 3

Circular depressions that are commonly funnel-shaped and can be a few feet to a hundred feet in diameter. They are the most commonly observed karst feature.

Question 4

Solution sinkholes

Answer 4

Occur when rainwater comes into contact with carbonate bedrock either directly or though a thin covering of soil.

Question 5

Cover-subsidence sinkholes

Answer 5

Form where sand overlies the carbonate bedrock.

Question 6

Cover-collapse sinkholes

Answer 6

Develop where there is a thick layer of clay above the soluble bedrock.

Question 7

Dripstone

Answer 7

A depositional karst feature of travertine deposits that result from the CaCO3-rich water dripping from the ceiling of a cave or cavern.

Question 8

Helictite

Answer 8

A depositional karst feature of an irregular twig like deposit that forms in a cavern where there is not enough water to form drips, but where the surface remains damp allowing the CaCO3 to grow in any direction

Question 9

Travertine

Answer 9

A depositional karst feature of a deposit of CaCO3 precipitate that can be found in limestone caverns coating the cavern walls, floors, and ceilings.

Question 10

Blind Valley

Answer 10

An erosional karst feature. It is a valley that ends at a swallow hole due to a prolonged period of upstream erosion above the sinkhole.

Question 11

Cavern

Answer 11

Large caves that may extend in any direction, have one or several levels, and are created by the solution of limestone along joints and bedding planes.

Question 12

Hum

Answer 12

Isolated hill remnants due to erosion by solution in karst terrain.

Question 13

Karst Window

Answer 13

A hole in the ground in which one can observe an underground stream flowing from one cavern to another. A hole in a cavern which breaks the surface.

Question 14

Lapies

Answer 14

Grooved or fluted surface resulting from the solution of limestone at or near the surface in an area of high relief. Grooves commonly result in knifelike ridges.

Question 15

Natural tunnels & bridges

Answer 15

Features produced by the underground flow of water in karst terrain. Bridges are formed when the tunnel sections collapse.

Question 16

Polje

Answer 16

An elongated basin with a flat floor and steep walls formed by solution of a previously faulted or folded structure.

Question 17

Sink

Answer 17

The point at which a sinking creek ends, often in an observable swallow hole.

Question 18

Sinkhole or Karst plain

Answer 18

A limestone plain exhibiting sieve-like characteristics resulting from numerous sinkholes intercepting any surface waters and diverting them to subsurface channels.

Question 19

Sinkhole ponds or karst lakes

Answer 19

A pond or lake resulting from the clogging of a (doline) sinkhole by clay that perches water above the water table.

Question 20

Sinking creeks

Answer 20

Any surface creek or stream which disappears underground in karst terrain. Many disappear in a swallow hole.

Question 21

Solution valley or karst valley

Answer 21

A transitional feature between surface and subsurface drainage in an area of clastic rocks. It is a special type of a blind valley.

Question 22

Solution-subsidence trough

Answer 22

A non-tectonic feature, up to 10 miles long, resulting from concurrent subsidence and solution along joints or faults.

Question 23

Swallow Hole

Answer 23

A hole in the bottom of a sinkhole which allows surface water runoff or streams to flow into the subsurface cavities.

Question 24

Terra rossa

Answer 24

A red clayey (CL-CH) soil found mantling the ground surface and extending into joints or fractures resulting from surface or near surface solution. It is usually found on moderate to gentle slopes.

Question 25

Uvala

Answer 25

An elongated karst window that has occurred by the collapse of an extensive portion of a subsurface waterway. These features can extend from 1000 ft to a mile or more.

Question 26

What did continental glaciation cover during the last Ice Age?

Answer 26

Central and northern U.S.

Question 27

Where is Alpine glaciation found?

Answer 27

Mountainous areas of Alaska, in the higher elevation of the Rockies, the Sierras, and the Cascades.

Question 28

Drift

Answer 28

It is all rock and associated material that has been carried by and deposited by a glacier, glacial ice, or water running from a glacier.

Question 29

Drumlin

Answer 29

An elongated ellipsoidal feature which can be composed of a wide variety of material ranging from till to relatively large rock fragments. The streamlined hills are usually clustered and found near the terminal or recessional moraines.

Question 30

Esker

Answer 30

Serpentine shaped stratified deposits that develop as the load carried by the stream flowing beneath, within, and above the glacier, once the glacier becomes stained and is dropped.

Question 31

Kame & Kame terrace

Answer 31

A small hummock or terrace of ice-contact drift that has resulted from the deposition of sediment either in crevasses at the surface of the glacier, or on the irregular surface of stagnant glaciers, or from streams flowing at the edge of the glacier along the contact of the ice with the valley wall. Sediments are usually stratified and contain poorly sorted sands (SW) and gravels (GW).

Question 32

Kettle

Answer 32

A depression in the postglacial terrain formed by the melting of a large stagnant ice bock which allows for the settlement of the overlying glacial drift.

Question 33

Arcuate terminal moraine

Answer 33

An arcuate moraine that has been deposited at the terminus of the glacier. marking the furthest progression of the glaciation.

Question 34

Ground moraine

Answer 34

Can be composed of both the material contained within the glacier and the material being moved at the base of the glacier.

Question 35

End moraine or Terminal moraine

Answer 35

Found at the maximum extent of a continental glaciation.

Question 36

Recessional moraine

Answer 36

Moraines that have formed during a temporary hiatus in the retreat of the ice sheet.

Question 37

Outwash plain

Answer 37

A broad plain composed of outwash: stratified depbirs that is carried by meltwater streams both in front of and beyond the terminal or end moraine. The outwash plain is typically comprised of coarser grained materials (SW, GW) closer to teh terminus of the glacier grading to finer materials with increased distance.

Question 38

Swell & Swale topography

Answer 38

Till deposits rich in clay that may result in a gently undulating surface whihc often is also found in areas that have had multiple glaciations

Question 39

Till

Answer 39

An unsorted, unstratified glacial deposit composed of a herterogenous mixture of clay (CL), silt (ML), sand (SW), gravel (GW), and boulders. It is usually unconsolidated and deposited directly by a glacier

Question 40

Lacustrine Plains

Answer 40

A plain that has formed by the filling of a lake with lake sediments and alluvium which has been deposited along the margin of the glacier. Characterized by very flat alley bottoms in hilly terrains.

Question 41

Moraines

Answer 41

A mound or ridge composed of accumulated of accumulated glacial drift or till deposited directly by the glacier. Composed of a heterogenous collection of unsorted and unstratified clay (CL), silt (ML), sand (SW), gravel (GW), and boulder. Many large clasts are faceted and have striations or polish due to abrasion while the glacier moved.

Question 42

Arête

Question 43

Cirque

Question 44

Col

Question 45

Fjords and Fiards

Answer 45

A submerged glacial trough or valley at its seaward end resulting from the raising of sea levels as the glacier melts.

Question 46

Fiards

Question 47

Glacial polish

Question 48

Glacial steps or stairway

Question 49

Glacial Trough

Answer 49

A steep-sided valley that extends down from the cirque in which glacial action has widened and deepened an existing valey.

Question 50

Hanging Valley

Question 51

Horn

Question 52

Monuements (tinds)

Question 53

Paternoster lakes

Question 54

Tarn

Answer 54

A small deep lake formed in a cirque basin

Question 55

Trough Lakes

Question 56

Truncated or faceted spur

Answer 56

A ridge in a pre-glacial valley that has been truncated by the abrasion of glacial action as it straightened the valley.

Question 57

Alluvial Fans: How do they develop? Grain sizes and sorting?

Question 58

Base Level

Question 59

Bed Load

Question 60

Runoff

Question 61

Sheet Flow

Question 62

Sheetwash

Question 63

Deltas

Answer 63

* Occur when streams enter lakes or seas and the flow branches out. Sedimentation occurs because of the change in gradient. * Topset and bottomset beds consist of deposiuts of finer grained silts (ML) and clays (CL)

Question 64

Gravel Bars | (Sand Bars)

Answer 64

GP and SP can develop midstream when the flow velocity of the water declines where it borders with a higher velocity in the stream. Bars are usually linear in the flow direction. Often relatively well sorted or poorly graded deposits.

Question 65

Natural Levees

Question 66

Braided Stream

Question 67

Stream Terraces

Question 68

Ripple Marks (2 types)

Answer 68

Asymmetrical ripple marks indicate directional current. Symmetrical ripple marks indicate oscillating water.

Question 69

Peneplains

Question 70

Pediments

Question 71

Inselbergs

Question 72

What are 3 proceeses that need to occur to develop a stream channel?

Question 73

Where do meander streams occur

Question 74

How do Parallel Streams develop?

Question 75

Dendritic Streams

Question 76

Radial Pattern Streams

Question 77

Deranged Stream Pattern

Question 78

Braided Stream Pattern

Question 79

What 3 Stream patterns occur with lithologic or structural control?

Question 80

Wave Cut Beach or Wave Cut Platform

Question 81

Marine Terrace

Answer 81

A wave-cut platform that has been exposed onto and by uplift or a lowered sea level.

Question 82

Headlands

Question 83

Sea Cliif

Answer 83

Scarp-like features found at the seaward side of marine terraces and are caused by erosion from wave action

Question 84

Sea Arches and Caves

Question 85

Stacks, Chimneys, or Skerries

Question 86

Order of stability of minerals under weathering:

Question 87

What are the soil horizons?

Question 88

What is the O-horizon

Question 89

Describe O-Horizon in humid, semi arid, and arid environments

Answer 89

Humid - O-horizon has thick accumulations of plant matter

Question 90

Describe A-Horizon: Humid Semi arid Arid

Answer 90

Humid - has a very thick zone of eluviation resulting in nutrients for plants Semi Arid - moderately thick zone of eluviation. is rich in organic matter and high in soluble minerals. Arid - a thin to nonexistent zone of eluviation. More coarse textured because of little precipitation. Soluble salts can precipitate from the water and accumulate in the soil.

Question 91

What is the A - Horizon

Question 92

What is the B-Horizon?

Question 93

Describe the B-Horizon in environments: Humid Semi Arid Arid

Question 94

What is the C-Horizon?

Question 95

Describe C-Horizon in these environments: Humid Semi Arid Arid

Answer 95

Humid - it is very deep Semi Arid - it is moderately deep Arid - It is very near the surface and relatively intact

Question 96

Till Plain

Answer 96

Also called ground moraine, deposition by an ice cap of glacial till forming a relatively flat to undulating surface which covers an extensive area and buries preglacial topography.

Question 97

Ice-scoured Plain

Answer 97

An assemblage of erosional landforms on exposed bedrock resulting from the flow of an ice cap. It exhibits many of the same surficial features that are found in areas of alpine glaciation like: striations, grooves, and polished surfaces, as well as the development of roche moutonées or mammillated surfaces.

Question 98

Roche Moutonée

Answer 98

An elongated bedrock knob which is oriented parallel to the direction of glacial flow and has a smooth rounded upstream end and usually a steep rough downstream end where the glacier plucked out the rock as it moved away.

Question 99

Streamlined topography (mammillated surface)

Answer 99

A series of smooth rounded erosional rock mounds alternating with parallel valleys resulting from the smoothing off of a mountainous region by the ice cap.

Question 100

Knob & Basin Topography

Answer 100

Also called knob and kette topography. A hummocky landscape consisting of knols or mounds of glacial drift in an area interspersed with basins or kettles. Basins often contain water.