geo #4

What is a spit and a tombolo and are they erosional or depositional?

A tombolo is a growing sandpit. Spit bars and tombolo can take on may different shapes as they bend, curve and shift during their evolution. They are depositional.

How does glacial abrasion work and what does it leave behind?

Glacier abrasion works when rocks are frozen to base cause the glacier to work like sandpaper. It leaves scratches on the rock..

Who was Ralph Bagnold and what did he contribute?

He laid the foundations for the research on sand transport by wind

What is an ice sheet and where do we currently find them?

Ice Sheets are sheets of ice they are the biggest continental glaciers. They are in Greenland and Antartica

What is a rejuvenated stream? What is a notable landform that was created by one?

One that has newly increased its erosive power and cuts downward into its own floodplain and other alluvial deposits; caused by either a relative fall in the streams bas level or the tectonic uplift of the valley.

What is roche moutonnee? How is it formed and is it erosional or depositional?

POWER POINT #19 PAGE 10

What is the difference between physical and chemical weathering?

Physical weathering is caused by natural occurrences, Chemical Weathering evolves water and other substances

What is pock beach?

Pocket beach is usually a small beach, between two headlands. In an idealized setting, there is very little or no exchange of sediment between the pocket beach

Be sure to study the physiographic realms and which landforms are found in which realm.

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Is the Earth currently gaining or losing glacial ice?

The earth is losing glacial ice.

What is the definition of horn? How is it formed and is it erosional or depositional?

The horn is sharp and pointed. It remains when several cirques attain their maximum growth by head ward erosion and intersect and fall. Leaving the Horn.

What is the "angel of repose?

The maximum angle at which a slope remains stable. At 36 degrees it becomes unstable. Knowing the angle of response you will know how stable the area is.

What is erosion?

The natural process by which wind, water, ice or gravity transports soil and sediment from one location to another

What is denudation?

The overall effect of disintegration, wearing away, & removal of rock material that lower the surface of continents. it is the process of weathering and erosion constantly wear away the rocks on the earths surface

Explain the mass wasting, falls, slides and flows.

The spontaneous down slope movement of earth's materials under the force of gravity. Landslides, rock falls, volcanic lahars also called Mass Movement

What is Geomorphology?

The study of the origin and history of land forms not just mountains.

What is depositional landforms?

They are the results of erosional landform deposits. The sediments from the landforms are carried though water and slowly chip away to make the landscape over time.

What is drumlin? How is it formed? Is it erosional or depositional?

This is a smooth steep sided hill elliptical in shape. Drumlins almost always occur in groups and there are drum fields. They develop beneath the ice and follow the pattern of the glacier movement, it is believed they are formed when the ice sheet erodes away material. DEPOSITIOANL

Explain the process of salt-crystal growth. Where do we find this process and is it physical or chemical?

This is when a lot of salt crystals grow and can split rocks. You find this process in the deserts and coastal areas. When H2O enters joints, evaporates, and leaves behind salts which wedges rocks apart. This is physical.

What is frost wedging? Where do we find this process? Is it physical or chemical.?

Water gets into cracks in rock, FREEZES, and EXPANDS THE CRACK. This process if found in colder areas. This process is physical.

Explain the concept of wave refraction and what it does to coastlines over time.

When a wave approaches a beach at the oblique angle, only part of it is slowed down at first, the part that first reaches shallow water. The rest of the wave continues to move at a higher velocity. This process obviously bends the wave as the faster end overtakes the end already slowed by shoaling. The bending is known as wave refraction. This would leave some parts of the beach behind the islet with waves approaching parallel to the shore and others with waves approaching at an angle. Waves breaking at an angle on some areas of the beach would thus lead to the removal of sediment by long shore drift.

What is a bay mouth bar and is it erosional or depositional?

When sandpits continue to grow all the way across the mouth of the bay. Another one is the offshore bar aka sandbar. which is some distance from the beach and is not connected to land. They are depositional.

Explain the process of hydrolysis. Where do we find this process and is it physical or chemical.

When water molecules separate to release hydrogen ions, and those ions then react with minerals. This is chemical weathering.

How do star, barchans and transverse dunes form?

Where star dunes are present, an area's wind regime is complex. Star dunes form only in places where wind blows from varied directions over the course of a year. To me this is part of a parabolic dune; As the sand supply increases, Barchan dunes begin to connect with others forming barchanoid ridges. If the ridges become fairly straight, scientists call them transverse dunes (below). Transverse dunes are believed to form when the sand supply is quite large and the prevailing strong winds blow from on direction.

What is Aeolian.

Wind erosion that is dependent on wind velocity and air density. A large assemblage of fluvial landforms (braided streams, terraces, ... or sedimentary structural dome or basin where erosion has exposed rimming .... left behind migrating dunes and /or storm wash over sediments; may be either barren or vegetated.

Forms of Mass Movement

You will need to distinguish them is by the type of downhill motion. 1) creep 2) slide movement 3) flow movement 4) fall movement.

Fully explain how a meandering stream works?

a river channel with distinct bends called meanders. This meandering channel patter is common and meanders themselves change over time in predictable ways. They tend to be downstream and begin with alluvium.

What is exotic stream? Can you drink the water?

a stream (such as the Nile) that has its source in well-watered lands and crosses a desert on its way to the sea. sustained by water that originates outside the desert, it comes from an adjacent wetter areas or a higher mountain area in the desert. Ex: Nile River, Colorado River. Stretches of the Mississippi River within the park corridor exceed water quality standards for mercury, bacteria, sediment, PCBs (polychlorinated biphenyl), and nutrients. Unfortunately, these "impairments" can make the water unsuitable for fishing, swimming, and drinking.

Explain ice regelation and rock plucking.

ice regelation is refreezing of melted glacial ice. The refreezing causes surface rocks and debris to get incorporated into the glacier.. Rock Plucking is when the glacier pulls the rocks out of the ground and carriers them internally across the ground.

What is kettle? How is it formed? Is it erosional or depositional?

in some places large blocks of ice are initially buried in the outwash plain. when these blocks melt they create steep sided water filled depressions known as kettles. DEPOSITIONAL

Glacial Landforms

landforms made by either the ice or the meltwater of a retreating glacier. Examples are: moraines, drumlins, kames, outwash, eskers, kettles, and kettle lakes Cirque, arete, Horn, Col, and trough 1. Valley Glaciers- tend to accentuate the landscape (make it sharper) Moraine- soil left behind by glacier • Cirque: Bowl forms initially below firn ice. Water from melted firn ice percolates through the bergschrund into fractures in the rock below • Hanging valleys: tributaries of larger glaciers higher up on the glacial wall. • Cirque: Bowl forms initially below firn ice. Water from melted firn ice percolates through the bergshrund into fractures in the rock belo

Study WM Davis drawings of alpine glacial erosion. You should be able to explain what happens from the beginning to the end.

power point #17 page 5

What are the three depositional landforms created by Aeolian forces?

sand dunes, bERM, SOME DESERTS

Explain point bars, cut banks, oxbow lakes and meander scars, braided streams

A cut bank, also known as a river cliff or river-cut cliff, is the outside bank of a water channel (stream), which is continually undergoing erosion.[1] Cut banks are found in abundance along mature or meandering streams, they are located on the outside of a stream bend, known as a meander, opposite the slip-off slope on the inside of the bend. They are shaped much like a small cliff, and are formed by the erosion of soil as the stream collides with the river bank. As opposed to a point bar which is an area of deposition, a cut bank is an area of erosion. Typically, cut banks are nearly vertical and often expose the roots of nearby plant life. Given enough time, the combination of erosion along cut banks and deposition along point bars can lead to the formation of an oxbow lake. Not only are cut banks steep and unstable, they are also the area of a stream where the water is flowing the slowest at a higher pressure and often deeper, making them rather dangerous. Geologically speaking, this is known as an area of high-energy. Material eroded here is deposited downstream in point bars. Oxbow lakes : when the stream will break through and cut off the meander entirely. The cutoff channel may retain water and form a crescent shaped oxbow lake. Braided Streams are patterns involving multiple stands of flowing water separated by sand , or islands.

What are distributaries and deltaic islands? Are they erosional or depositional landforms?

A distributaries is: As the river flows onto the delta, streamflow generally separates into multiple channels call distributaries, which carry the rivers water in several directions. Each distributaries may divide several times before reaching the ocean. Deltaic Islands form as the sediment is deposited by the river overwhelm the less effective work of waves and currents creating the deltaic. They are both Depositional landforms.

What is a glacier and how does it form?

A glacier is a large mass of ice. Either resting on land or adjacent to land floating in the sea. It is formed by continual accumulation of snow the recrystallizes under its own weight into an ice mass.

What is headland ? Is it erosional or depositional?

A headland of considerable size often is called a cape. Headlands are characterized by high, breaking waves, rocky shores, intense erosion, and steep sea cliffs with water generally on three sides. it is erosional.

How does a natural levee form and how does it prevent flooding?

A natural levee is sediment that has been deposited. As the river spills out of its channel, the coarsest material is carries is deposited closest to the overflow and creates the levee.

What is a lagoon and is it erosional or depositional?

A normally shallow body of water the lies between an offshore barrier island and the original shoreline. It is erosional.

what is a paternoster lake?

A paternoster lake is one of a series of glacial lakes connected by a single stream or a braided stream system they say to appear like rosaries beads. Paternoster lakes occur in alpine valleys, climbing one after the other to the valley's head, Paternoster lakes are created by end moraines, or rock dams, that are formed by the advance and subsequent upstream retreat and melting of the ice.[

what is the definition of truncated spur? How was it formed and is it erosional or depositional?

A truncated spur Is a spur of hillsides that have been cut off by a glacier, thereby straightening the glacially eroded valley. Glaciers shear off many of the mountainside spurs around which rivers once flowed which causes the straightening.

How does a watershed work and why is it important to study?

Also known as a drainage basin: Is a region occupied by a complete stream system formed by the trunk river and all its tributaries. A river system consists of a trunk river joined by a number of tributary streams, which are themselves are fed by smaller tributaries. These branch streams diminish in size the farther they are upstream from the trunk river. The complete system of the trunk and its tributaries forms a network that occupies a region known as a drainage basin. ONE well known Watershed is the Mississippi Basin the Mississippi river is in the trunk and the Missouri and Ohio rivers are chief tributaries.

What are saltation and surface creep in Aeolian sediment transport?

Also spelled ; EOLIAN. WHICH MEANS WIND RELATED PROCESS. Coarser particles are too heavy to be picked up and carried very far the wind still moves them and they may tend to bounce on the ground at a high rate of speed. This is called SALTATION. Aeolian (wind transport process) can also push a rock along the surface this is called SURFACE CREEP

Explain the problems with using the Colorado River for water.

Any untreated water has the potential to cause illness if it is not properly and carefully disinfected.

What is the definition of arête? How is it formed and is it erosional or depositional?

Arêtes are sharp like ridge and they are erosional. These ridges frequently separate adjacent glaciers or glacial valleys.

What are the types of dunes and explain their movement.

Barchans, Transverse, Longitudinal, and Parabolic They are moved by the wind.

Explain the process of carbonation. Where do we find this process and is it physical or chemical

Carbonation occurs when carbon dioxide gas dissolves in water and reacts with the water to form a mildly acidic solution. More specifically, the reaction of CO2 and Water h20 forms carbonic acid H2CO3. Some of carbonic acid then separates into bicarbonate and hydrogen ions.

Explain the process of oxidation. Where do we find this process and is it physical or chemical.

Chemical combination of oxygen and other materials to create new products. biologist call this process respiration. When iron bearing silicate minerals are broken down by weathering some of the iron is released and will change the rock color this is a chemical weathering.

What are the differences between valley, cirque and tidewater glaciers? Are they Alpine or Continental?

Cirque glaciers are bowl shaped erosional landforms at the head of a valley. Valley Glaciers is ice confined within the valley that was originally formed by stream action it is erosional. Tidewater glaciers are glaciers that end at the sea by breaking off into ice bergs.

What is deposition?

Deposition of Sediment: Is when deposits of sediment in distinctive pattern.

Explain the process of exfoliation. Where do we find this process and is it physical or chemical.

Exfoliation in Granite: Granite forms underground as its cooling then stuff happens and the granite works its way up and it exposed so it explodes to create the domes. It is a special kind of jointing that produces a joint patter resembling a series on concentric shells, much like the layers o an onion. Following pressure the outer layer peal away to expose the inner layer. It is physical weathering.

What does fluvial mean?

Flowing or running water

What are the three ways in which fluvial erosion occurs? Explain them

Fluvial erosion relates to stream related. It is a powerful force in denudation. It is the geomorphic process associated with flowing water. Fluvial landforms are depositional. Fluvial processes include the motion of sediment and erosion or deposition on the river bed.

What is esker? How is it formed and is it erosional or depositional?

Glacial outwash landform that appears as a long ribbon like ridge in the landscape because it was formed by the clogging of a river course within the glacier, the debris from which remains after the ice melts. " not compelted"

What is weathering?

Is the breakdown of rocks in place. Weathering sets the stage for erosion. Gravity is part of weathering. Weathering can be chemical or physical. Weathering does not move the rock it only breaks it down. Weathering is caused by climate, Orientation of slope, vegetation, jointing of rock and character of bedrock. Chemical weathering is the decay due to chemical alteration always in the presence of water. Spheroidal Weathering is when water works into cracks and causes rounded surfaces.

When can you expect the next 100 year flood?

It is not a sure thing. It is only an estimate for insurance companies to base flood insurance rates on. EST 10 YEARS

What is Karst? How does it form and what are the features associated with it.

Karst is the chemical weathering of soluble rocks, primarily limestone. This is when a rock is dissolved and is carried away by groundwater. The results are caverns and sinkholes.

What is a littoral drift?

Littoral transport is the term used for the transport of non-cohesive sediments, i.e. mainly sand, along the foreshore and the shore face due to the action of the breaking waves and the long shore current. The littoral transport is also called the long shore transport or the littoral transport.

What is the definition of moraine. How is it formed and is it erosional or depositional?

Moraine: A ridge or mound of glacial debris deposited during the melting phase of a glacier. Larger rock fragments are often deposited in ridges of debris called moraines. They are depositional.

Do we worry about sinkholes in California?

No, because California does not have a lot of water like Florida. Florida needs to worry about sinkholes.

What is Aeolian deflation and what landform it leaves behind.

Regions which experience intense and sustained erosion are called deflation zones. Most Aeolian deflation zones are composed of desert pavement, a sheet-like surface of rock fragments that remains after wind and water have removed the fine particles. Almost half of Earth's desert surfaces are stony deflation zones

What is a natural levee?

River-lining ridge of sediment and mud deposited when a stream overflows it banks during a periodic flood. When the river contracts after the flood, it sys within these self-generated "dikes" aka levee.

Explain Aeolian abrasion and how is it forms ventifacts and yardangs

Sculpted landforms, called yardangs, are up to tens of meters high and kilometers long and are forms that have been streamlined by desert winds. The famous Great Sphinx of Giza in Egypt may be a modified yardang.

What is sea stacks and is it erosional or depositional?

Sea stacks are remnants of headlands they stand alone as columns. The are erosional.

What is alluvium?

Sediment laid down by a stream on its valley floor. Deposition occurs when the streams velocity decreases and the valley fills with a veneer of unconsolidated material. Sine soil particles washed from slopes in the drainage basin form a large part of these deposits, these soils are usually fertile and productive.

What is the basic relationship between stream load and stream capacity?

Stream capacity is the maximum amount of sediment that a stream can carry with a given amount of water. Steam load. Stream load is a geologic term referring to the solid matter carried by a stream

What is the definition of tarn? How was it formed and is it erosional or depositional?

Tarn: Small circular lake on the floor of a cirque basin. When climate is warn that cirques are no longer filled with snow, small circular lakes are found. These lakes dammed up behind the "lip" of the cirque are known as tarns.

What is alluvial fan and bajada?

The alluvial fan is a sequence of events when ephemeral streams emerge from desert mountains. an alluvial fan is fan shaped deposit consisting of alluvial material located where a mount sterema emerges into the plain.

What is base level and how does it relate to streams?

The base level is the elevational level below which a stream cannot erode its bed. No stream can erode its base level. Sea level is the ultimate base level.

What is the definition of hanging valley? How is it formed and is it erosional or depositional?

also known as a hanging trough happens when both glaciers melt away, the valley of the tributary glacier, as viewed from the floor of the main glacier, seem to "hang" high above. Thus called hanging valley erosional.

What is erosional landforms?

as a rock is eroded away it will develop an erosional landform is where the bay reaches the sea. Limestone is very susceptible of erosional landform. As the rock is eroded away it will develop erosional landscape.