Sediment as you know, is material like sand, gravel, fossil fragments that is transported by natural processes like wind, water flow or the movement of glaciers.

如你所知，沉积物是通过风、水流或冰川运动等自然过程输送的物质，如沙子、砾石、化石碎片等。

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The water was always laden with pebbles, gravel, and sand, known as glacial outwash, that was deposited as the flow slowed down.

水里总是遍布鹅卵石、砾石和沙子——它们被称为冰水沉积，是在水流减缓时沉积下来的。

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The commonest spaces are those among the particles—sand grains and tiny pebbles—of loose, unconsolidated sand and gravel.

最常见的空间是那些由松散的、未固结的砂和砾石组成的颗粒（沙粒和小卵石）之间的空间。

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This plant turns debris from buildings - many destroyed by Israeli air strikes - into sand and gravel that is then turned into cinder blocks for building.

VOA: standard.2010.06.16

The quarry is owned and run by Cemex, which extracts sand and gravel from the site.

BBC: Kingsmead Quarry 'beaker burial' woman is rare find

If approved the quarry would release five million tonnes of new sand and gravel reserves.

BBC: Ducklington's Gill Mill quarry expansion planned

Major activities in the area are agriculture, forest management, sand and gravel extraction, industry (diverse types), and ecotourism.

UNESCO: EDUCATION