Astronomy quiz question: Mercury's lobate scarps

Astronomy 210 Quiz 7, Fall Semester 2010
Cuesta College, San Luis Obispo, CA

__________ caused the long curving ridges on the surface of Mercury.
(A) Lava flooding in lowland basins.
(B) Compression and shrinking of the crust.
(C) Convection currents underneath the crust.
(D) Vertical motion of magma under the crust.

Correct answer: (B)

Mercury's rupes, or lobate scarps, were formed as its relatively thin crust wrinkled and shrank as its massive underlying core cooled and contracted.

Section 70158
(A) : 2 students
(B) : 25 students
(C) : 11 students
(D) : 5 students

"Success level": 60% (including partial credit for multiple-choice)
Discrimination index (Aubrecht & Aubrecht, 1983): 0.75