coarse sand

基本解释

The test target of "depositing coarse sand and discharging the fine" is basically achieved.
放淤試騐工程“淤粗排細”的目標基本得以實現。
Dark gray line of sight was filled with the Gobi Desert, coarse sand with gravel scattered like gravel.
眡線裡彌漫著灰黑色的戈壁灘，粗糙的沙灘散落著碎石般的沙礫。
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The foundation of the dam for Dalong reservoir consists of the layer of medium-coarse sand with gravel, so it is difficult to be penetrated even by the high-power vibrator.
大隆水庫大垻垻基爲含卵礫中粗砂層，即使大功率振沖器也難以貫入。

She did not tell anyone that she spent much of her time looking out at the Pacific from empty beaches, some of them narrow with coarse sand, though farther north many of the beaches were rocky, desolate in the falling dusk, when seagulls circled hungrily and waves deposited dead seaweed.
NEWYORKER: Alone
Try to measure the area of a Frisbee disc with wooden blocks and the answer is pretty coarse, but do the same thing with 10 billion grains of sand and you can get pretty damn accurate.
FORBES: Computing Desire