Pillow basalts,shown below,attain their distinctive blob-like shapes because their parent lavas do not travel far prior to solidification.This is because the parent lavas ____________.

A)are completely devoid of volatiles and thus travel slowly
B)erupt underwater and thus cool very quickly
C)are highly felsic and thus travel slowly
D)are ultramafic and thus freeze at exceptionally high temperatures

Question

Pillow basalts,shown below,attain their distinctive blob-like shapes because their parent lavas do not travel far prior to solidification.This is because the parent lavas ____________.

A)are completely devoid of volatiles and thus travel slowly 
B)erupt underwater and thus cool very quickly 
C)are highly felsic and thus travel slowly 
D)are ultramafic and thus freeze at exceptionally high temperatures

Quizplus · Accepted Answer

Pillow basalts are formed when basaltic magma erupts underwater and quickly cools, forming characteristic blob-like shapes. The rapid cooling prevents the lava from flowing far before solidifying into these puffy, pillow-like structures.

Pillow Basalts,shown Below,attain Their Distinctive Blob-Like Shapes Because Their Parent