Q&A Hero

Q: Salt wedging is a weathering process that is more common in humid areas than arid.

Q: Middle-latitude deserts and steppes are more numerous and extensive in the Northern Hemisphere than in the Southern Hemisphere.

Q: The world's driest desert is the Atacama Desert in South America.

Q: The world's largest arid desert is the Sahara.

Q: A true desert is defined by how hot it is.

Q: The central United States is covered with extensive deposits of loess. Where did this loess come from? A) Alluvium deposited during major floods B) Rock flour from the braid plains of Pleistocene glacial streams and rivers C) Decomposing sandstone from the St. Peter Sandstone D) Weathering and erosion of western mountains

Q: Deposits of silt carried by blowing winds are referred to as ________. A) deflation deposits B) loess C) eolian sands D) alluvium

Q: ________ are mounds and ridges of sand that are deposited by the wind. A) Ventifacts B) Desert pavements C) Blowouts D) Dunes

Q: What are the two primary sources for loess? A) Lakes and streams B) Deserts and glacial deposits C) Atmosphere and volcanoes D) Shallow seas and lakes

Q: The ________ was a period of drought in the 1930s in the United States that resulted in significant dust storms blowing fine sediment for hundreds of miles. A) Dust Bowl B) driftless area C) rainshadow D) basin and range

Q: What is a yardang? A) A wind-sculpted landform oriented parallel to the prevailing wind, often narrow at the base B) A small rock polished and pitted on the exposed surface C) A shallow depression created by deflation D) A pit worn into a rock by circular currents of flowing water

Q: A(n) ________ is a smooth, polished rock that has been abraded by the wind. A) blowout B) bajada C) inselberg D) ventifact

Q: There is no one maximum depth for desert blowouts. They vary in depth depending on conditions present at the location. What controls the depth of all blowouts? A) Force of the moving wind B) Velocity of water eddy C) Elevation of water table D) Amount of water available for dissolution of underlying materials

Q: What process creates desert blowouts? A) Moving water B) Evaporation C) Herd animals pawing at the ground D) Deflation by wind

Q: Which mechanical weathering process will be most common in an arid environment? A) Salt wedging B) Abrasion C) Root wedging D) Exfoliation

Q: Which set of characteristics would best fit a geologically recent fault block mountain uplift? A) Large, broad bajadas with many inselbergs B) Small playas and large alluvial fans C) Flat upland surface, steep slopes, and small alluvial fans D) Extensive playas ringed by large sand dunes

Q: Which one of the following statements about landforms is correct? A) Alluvial fans typically rim desert valleys. B) Playas form on high cuestas in arid areas. C) Inselbergs are composed of coarse sands and gravels. D) Inselbergs are found in low, circular depressions.

Q: Why is it so difficult for wind to pick up clay-sized particles? A) They are too large for the wind to carry. B) The wind has a near-zero velocity closest to the surface and can't pick them up. C) The clay particles are often buried under larger sediments. D) There is too much clay to carry.

Q: Which size(s) of sediment commonly make up most of wind's suspended load? A) Sand B) Clay C) Silt D) Gravel

Q: ________ refers to the bouncing motion sands will display when transported by moving water or wind. A) Yardang B) Saltation C) Deflation D) Slithering

Q: How was the Salt Pan at Death Valley created? What is the name of such a desert feature? A) Stream erosion; wadi B) Precipitation; nullah C) Evaporation; playa D) Chemical reactions; ephemeral

Q: Inselbergs are generally associated with a(n) ________ stage desert landscape. A) early B) middle C) late

Q: Why doesn't interior drainage, such as the drainage that develops in deserts, flow out of the desert? A) The water flows underground. B) The water fills large lakes. C) The water evaporates. D) The water freezes.

Q: Which desert location in the United States consists of alternating mountain ranges and flat-bottomed valleys as a result of fault block mountains? A) Rocky Mountains B) Ohio River Valley C) Marathon Uplift D) Basin and Range Province

Q: Which of the following can contain large quantities of evaporite minerals such as borate and halite? A) Playa B) Inselberg C) Alluvial fan D) Bajada

Q: Which of the following desert landforms is carved from solid rock rather than consisting of accumulated sediments? A) Playa B) Inselberg C) Alluvial fan D) Bajada

Q: ________ weathering is most common in a desert environment. A) Mechanical B) Erosional C) Chemical D) Dissolution

Q: There are many names for ephemeral desert streams that remain empty for most of the year. Which of the following is not another name for an ephemeral desert stream? A) Arroyo B) Wadi C) Playa D) Wash

Q: What is the definition of an ephemeral stream? A) A distributary channel on a stream delta B) A stream that meanders back and forth across a valley C) A stream that has interweaving channels and is choked with sediment D) An intermittent stream that only has water after specific episodes of rain

Q: In a desert environment, in which area would surface water infiltrate into the local groundwater system most effectively? A) Playa lakes with thick mud bottoms B) Streams flowing across an alluvial fan C) Streams flowing across bare bedrock D) Steep-walled mountain streams

Q: Why do deserts lack thick deposits of soil? A) Low temperatures and high soil moisture contents accelerate chemical weathering. B) Warm temperatures and high soil moisture contents accelerate chemical weathering. C) Warm temperatures and low soil moisture contents allow some mechanical weathering. D) Temperature has no effect on rock weathering.

Q: Within water-deficient regions, two climatic types are recognized. What are they? A) Subpolar high and subpolar low B) Ephemeral and playa C) Desert and steppe D) Saltation and tropical

Q: Which of the following areas is known for its rainshadow deserts? A) The Sahara in Africa B) South America east of the Andes C) Central Iran D) Great Valley of Central California

Q: What percentage of Earth's land area is covered by dry regions such as deserts and steppes? A) 14 percent B) 30 percent C) 9 percent D) 50 percent

Q: Which of the following statements about deserts is true? A) Although rainfalls are infrequent, erosion and deposition related to water are important in deserts. B) Deserts are located where there are ascending air masses and low atmospheric pressure. C) Deserts are defined by their sand content. D) Deserts are always located in hot, humid coastal areas.

Q: Most dry lands exist between ________ degrees latitude on either side of the equator. A) 50 and 60 B) 35 and 40 C) 20 and 30 D) 0 and 10

Q: A true desert is defined by a lack of what substance? A) Oxygen B) Plant life C) Rocks D) Water

Q: From a climatological perspective, a region is a desert if ________. A) yearly precipitation exceeds evaporation B) yearly precipitation is equal to evaporation C) yearly precipitation is less than evaporation

Q: Traditionally, a region is defined as a desert if it receives less than ________ centimeters of rain per year. A) 10 B) 25 C) 15 D) 2

Q: Which crevasse will form perpendicular to the terminus as a glacier stretches to fill a valley? A) Esker B) Longitudinal C) Transverse D) Moulin

Q: Which crevasse will form parallel to the terminus as a glacier moves over a change in slope? A) Bergschrund B) Longitudinal C) Transverse D) Moulin

Q: ________ is an elevation point above which snow remains throughout the year. A) Firn B) Snowline C) Grounding line D) Surge

Q: The Laurentide Ice Sheet is an example of ________ glaciation. A) alpine B) valley C) continental D) ice cap

Q: Ice shelves are grounded in ________ and float in ________. A) saltwater; freshwater B) shallow water; deep water C) freshwater; shallow water D) deep water; shallow water

Q: Glaciers form because of the accumulation of large amounts of ice and snow. Which of the following provides the most water needed to create glaciers? A) Groundwater B) Geysers C) Oceans D) Streams

Q: Which of the following ice bodies is an example of alpine glaciation? A) Valley B) Ice Sheet C) Ice Cap D) Iceberg

Q: The Hubbard Glacier in North America is an example of which kind of glacier? A) Valley B) Ice Sheet C) Piedmont D) Cirque

Q: When was the Last Glacial Maximum? A) 18,000 years ago B) 10,000 years ago C) 100,000 years ago D) 32,000 years ago

Q: Which of the following locations does not currently have glaciers? A) Norway B) Antarctica C) Scotland D) Alaska

Q: What percentage of the Earth's land surface is currently covered by glacial ice? A) 2% B) 10% C) 15% D) 33%

Q: Match the image with the correct glacial erosional term. A) Cirque B) Horn C) Hanging valley D) Arte 1. 2. 3. 4.

Q: What kind of lake was Lake Agassiz in this image? A) Kettle lake B) Proglacial lake C) Pluvial lake D) Tarn

Q: What landform is present in this image? A) Drumlin B) Esker C) Kettle D) Horn

Q: The landform visible in this image is a drumlin. Based on the shape of the drumlin, which direction was the ice coming from? Assume that the top of the figure is north. A) North B) South C) East D) West

Q: How did erosion shape this glacial feature? (Hint: It is bedrock.) A) Frost wedging B) Plucking C) Abrasion D) Plucking and abrasion

Q: Which direction was the ice flowing (Hint: It is bedrock.) A) Bottom to top B) Left to right C) Top to bottom D) Right to left

Q: What erosional feature is visible in this image? (Hint: It is bedrock.) A) Arte B) Moraine C) Drumlin D) Roche moutonne

Q: What substance is responsible for the turquoise color of the water in this image? A) Till B) Outwash C) Oxidation D) Rock flour

Q: Which method of glacial erosion is responsible for the marks in this image? A) Abrasion B) Plucking C) Quarrying D) Jointing

Q: What evidence of glacial erosion is visible in this image? A) Crevasses B) Striations C) Faults D) Outwash

Q: Explain how the presence of glaciers on the planet affects the albedo of the land surface. How will the albedo change as glaciers melt? What will this mean for the climate?

Q: Compare and contrast proglacial lakes and pluvial lakes.

Q: Glacial Lake Agassiz went through many periods of catastrophic drainage starting at 13,000 years ago. Some of these periods of catastrophic change have been linked to periods of cooling climate, particularly when the lake drained through the St. Lawrence Seaway and into the North Atlantic. How would the drainage of Lake Agassiz affect the climate to such a degree that cooling would result?

Q: The Mississippi River currently makes up the western boundary of the state of Illinois. However, the Ancient Mississippi River Valley once flowed through the center of the state, cutting off one-quarter of the state from its modern boundaries. How did the Mississippi River shift from its ancestral location to its present one? How did it end up staying in its current location? Explain.

Q: During the Wisconsin Episode Glaciation, a glacial forebulge formed just off the coast of British Columbia in the vicinity of Queen Charlotte Island. What is a glacial forebulge and how did this one form?

Q: How is isostatic rebound affecting the Lake Michigan Basin?

Q: How does ground moraine form? Relate the formation of ground moraine to changes in climate.

Q: How does a glacial fjord form? What does it tell us about climate change after glaciation?

Q: Evaluate the following statement: "Continental ice sheets generally subdue their landscapes, whereas alpine glaciers accentuate them."

Q: What factors influence the rate of glacial erosion?

Q: The Zone of Fracture in a glacier is found in the uppermost 50 m of glacial ice. Explain why ice fractures above this depth, but not below.

Q: Match the glacial landform with the material it is made of. (Note: Some answers will be used more than once.) A) Solid rock B) Till C) Sands and gravels 1. Outwash plain 2. End moraine 3. Erratic 4. Esker 5. Drumlin 6. Arte

Q: Match the state of the glacier to the correct glacial budget. A) Incoming ice is equal to ablation. B) Incoming ice is less than ablation. C) Incoming ice is greater than ablation. 1. Glacial stagnation 2. Glacial advance 3. Glacial retreat

Q: Match the type of glacier with the correct definition. A) A long, narrow glacier that flows downslope B) A broad lobe that spreads out to flow on an open plain C) A small, round glacier at the head of a valley D) A large, massive glacier that moves independently of the topography 1. Valley glacier 2. Cirque 3. Piedmont glacier 4. Ice sheet

Q: North American glaciations used to be described in four episodes. However, two of those episode names, the Kansan and Nebraskan, are no longer used. What evidence did scientists use to redefine the glacial history on the North American continent?

Q: How does the formation of a hanging valley differ from the formation of the main glacial trough?

Q: What factor(s) might lead glaciers to basal slip?

Q: How does an ice cap compare to an ice sheet?

Q: When the three parts of the Milankovitch Cycle align, there will be harsher winters in the middle to high latitudes with less snowfall and warmer summers bringing an increase in snowmelt.

Q: The Earth is still in an Ice Age today because there are still glaciers on the planet.