Why are the regressive phases of cratonic sequences marked by unconformities? What will be an ideal response?


During regressive phases, sea level is falling, therefore sediments are exposed. When rocks
and sediments are exposed, weathering and erosion occurs. Deposition is also less likely to
take place on land. As a result of non-deposition and/or erosion, sediments are lost and
unconformities develop.

Environmental & Atmospheric Sciences

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Which one of these four main greenhouse gases is associated with the storage and application of nitrogen based fertilizers?

A. N2O B. NO2 C. CO2 D. CH4

Environmental & Atmospheric Sciences

A stream increases its channel slope as it moves downstream. If the water depth remains the same or decreases slightly, this stream will

A) deposit some of its sediment load due to a decrease in shear stress. B) erode additional sediment load due to an increase in shear stress. C) continue to carry the same sediment load as there is no change in shear stress. D) deposit some of its sediment load due to a increase in shear stress. E) erode additional sediment load due to an decrease in shear stress.

Environmental & Atmospheric Sciences

In arid climates, most small streams are ________

A) nonexistent B) ephemeral C) intermittent D) perennial E) without channels

Environmental & Atmospheric Sciences

____________________ ripple marks form in response to wind or water moving in one direction. Fill in the blank(s) with the appropriate word(s)

Environmental & Atmospheric Sciences