Explain why the sediment in windblown sand dunes is better sorted than the sediment deposited by a flooding river
What will be an ideal response?
Wind can only pick up a certain size fraction of particle sizes (roughly sand size). Therefore, wind-blown sand dunes are composed of sand-sized particles and are well sorted (particles are all of roughly the same size). In comparison to flood deposits, floods have more energy to pick up a large range of particle sizes and these deposits are poorly sorted.
You might also like to view...
Gravity is:
A) a force. B) an acceleration. C) an attraction between any two masses. D) all of the above
Once a parcel of air rises above the lifting condensation level, the rate of cooling slows because:
A) latent heat is released when water vapor condenses. B) the air surrounding the parcel is cooler. C) water droplets absorb visible light much better than water vapor does. D) the parcel of air continues to cool at the dry adiabatic lapse rate.
Geologists regard basaltic magma (Hawaiian lava, for example) as the result of the partial melting of ultramafic rock in the ________.
A. inner core B. oceanic crust C. outer core D. continental crust E. mantle
Why isn't manganese mined on the seabed when there are abundant manganese nodules in some parts of the ocean floor?
A) The manganese market is held by a global cartel who prevent the material from being mined. B) It is not economical to mine manganese nodules at present-day world prices for manganese and associated metals in nodules. C) The manganese is too difficult to extract from the nodules; a new technology is needed. D) It is impossible to extract the nodules from the seafloor with present-day technology.