The molecules of the soil or streambed would become smaller and simpler.

土壤或者河床的分子会越来越小，越来越简单。

youdao

A ridge, as of sand or gravel, on a shore or streambed, that is formed by the action of tides or currents.

沙洲，沙滩：在海边，河床等处由沙子或小石子形成的隆起，由潮水或水流运动而形成。

youdao

Use stones that mimic a natural streambed, although granite's blues and grays can make a striking visual impact.

用石头，模仿自然河床，虽然花岗岩的蓝色和灰色可以作出醒目的视觉冲击。

youdao

This is a transition from speculation about the size of streambed material to direct observation of it.

FORBES: Curiosity Finds Evidence Of Ancient Stream On Mars

Not to be outdone by its brother, Curiosity has found the first evidence of an ancient streambed on Mars near the Gale Crater.

FORBES: Curiosity Finds Evidence Of Ancient Stream On Mars

Mars rover Curiosity has found the remnants of an ancient streambed on Mars, providing still more evidence that water once flowed freely there.

FORBES: Curiosity Finds Evidence Of Ancient Stream On Mars