Rocks and sand on beaches become rounded rapidly because ________.
A)rip currents move the sand offshore rapidly,abrading the fragments
B)the swash action of waves rolls loose material up and down the beach,where it is abraded rapidly to produce rounded grains
C)Beach sand is mostly calcium carbonate from reefs and so gets rounded easily
D)There is nothing particularly prominent in beaches that produces more rounding than other sedimentary processes.

Question

Quizplus · Accepted Answer

The swash action of waves repeatedly rolls loose material up and down the beach, abrading the fragments against each other and smoothing them out over time, resulting in rounded grains. Rip currents do not contribute to the rounding of sediment on beaches, and the composition of beach sand varies depending on the location, so choice C is not a universally applicable explanation. Choice D is also incorrect because the unique environment of beaches with their wave action and sediment composition does contribute to more rapid rounding compared to other sedimentary processes.

Rocks and Sand on Beaches Become Rounded Rapidly Because ________