How do columnar joints form? What will be an ideal response?
In a lava flow, especially a mafic one, a distinctive pattern of columns bounded by fractures may form.
This occurs when the lava flow stops moving, contracts as it cools, and produces forces that cause
fractures to open. The fractures, called joints, appear as polygonal cracks that extend downward,
forming parallel columns with their long axes perpendicular to the cooling surface.
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Despite the recent warming of the troposphere, in 2009, the world's oceans were the coolest in 130 years of record keeping.
Answer the following statement true (T) or false (F)
Drainage winds are ____ winds
a. katabatic b. foehn-type c. Chinook d. tropical
Describe the advantages of pollution prevention efforts
What will be an ideal response?
All of the following are warm currents, EXCEPT
A. Canary Current. B. North Atlantic Drift. C. South Equatorial Current. D. Gulf Stream.