Physical Geography- Test 4
Name 3 types of dry lakebed, which has a heavy clay mixture and which one has a heavy salt content?
1. Playas 2. Salinas- Heavy salt 3. Claypan- Heavy clay
Sharp Angles in geography come from_____ and smooth angles come from _______?
Dry Climate and Wet Climates
ergs are ------
Seas of sand. sand dunes, originated in a more humid climate, wind created formation sahara and arabian deserts
what is the erg in desert in california called?
algodones
Name an exotic river/stream in Africa and 3 in the United States.
1. Africa- Nile River 2. US- Rio Grande 3. US- Mississippi 4. US- Colorado
Name the four most common dunes
1. Barchan 2. Transverse 3. Sief 4. Star
There are 3 characteristics of deserts, what are they? Briefly explain them, tell me which one is covered in sand, rock and/or exposed bedrock.
1. Ergs- "Sea of sand"- sand, contain sand dunes 2. Regs- stone covered deserts- no sand- aeolian 3. Hamada- barren bedrock, larger material than a reg, exposed bedrock/ sedimentary rock
List the 3 Erg deserts found in the US and tell me in what state they are located.
1. Great Sand Dune National Park Colorado 2. White Sands National Monument New Mexico 3. Yuna Dessert Arizona
Ina basin and range topography, the lowest areas are frequently occupied by a _______ and the highest area are occupied by ________?
1. Low- Playa, Playa Lake 2. highest- Range
Ten Conditions of Weathering- First 5
1. Weathering- mechanical weathering is dominant water shapes but mechanical weathering is dominant 2. Soil & Regolith- Soil Thin- exposing bedrock 3. Soil Creep- Minor in arid deserts Lacks water (a smoothing agent) 4. Impermeable surfaces [H2O]- caprocks, hardpans, high water runoff 5. Sand: sand abundance A. Basins of interior drainage B. Water infiltrates/ no rivers C. Heavy rain and wind move sand
Next 5 of 10 conditions
6. Rainfall- Limited, Flashh Floods, Thunderstorms- Rain Fluvial deposits 7. Fluvial Deposition- Major agents of erosion- water is king! 8. Wind- wind shifts particles, aeolian erosion 9. Basins of interior drainage- water stays in the basin doesn't drain to ocean. Eater major landform agent 10. Vegetation- lack of continuous vegetative cover
What is bajada and what is another name for it?
A. Are several alluvial fans joined together B. Coalescing alluvial fans
How do Bornhardts differ from other inselbergs? What landscape do we find them in?
A. Bornhardts- rounded hills, weather resistant B. Landscape in areas surrounded by plains
What zone we find at the base of a mountain range in a desert environment, is it an area of fluvial deposition?
A. Pediment B. It is Fluvial deposition
Is deflation a fluvial or an aeolian erosion? Then describe deflation.
A. aeolian erosion B. shifting of love particles
Aeolian erosion
Aeolian- wind erosion airborne sand and dust
Alluvial fan forms ________
Cove the piedmont zone and pediment
What are inselbergs?
Desert Islands- iNSELBERGS- steep mountains, hills and rounded hills Bornhardts- rounded hills and weather resistant
In the three characteristics of deserts, where do their rivers drain?
Downstream
In a basin and range topography which occupies the highest and lowest areas?
Highest- Range Lowest- Playa/Playa Lake
Barchan dunes are ______.
Individual dunes, non sandy surfaces, crescent shaped and wind in one direction
Sief dunes are ______.
Long, narrow and parallel. Wind blows in 2 directions
What is the piedmont zone?
Mountain and pediment meet
What is the best example of Exotic Stream/ Desert River?
Nile River
Most weathering in a karst topography is chemical, is major weathering in a desert environment also chemical, if not what then?
No, it is mechanical weathering
Star dunes are ________.
Not common, pyramid shaped dunes, wind blows from all directions.
What is abrasion?
Pitting and etching of rock through wind patches
Transverse dunes are ______.
Supply of sand greater than barchans, crescent shaped, entire landscape is dunes
What is the major agent responsible for landscape formation of deserts?
Water
aeolian is what type of erosion?
Wind erosion
Does water (fluvial process) erode more than wind (aeolian process) in the desert?
Yes
Which two sand dunes are crescent shaped?
barchan & transverse
basin and range terrain has no ________.
external drainage to the ocean.
what are exotic streams?
permanent streams formed outside of arid lands
What is the lowest to hight basin and range terrain?
playa/playa lake, basin, then range
ephermal streams
short terms- alluvium is common in deserts
Explain what pediment is in a desert environment.
zone at the foot of a mountain range/bedrock
