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How do cave sediments enter underground passages?

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cave Stalactites and stalagmites in the Queen's Chamber, Carlsbad Caverns National Park, southeastern New Mexico.

Cave sediments enter underground passages through several primary mechanisms, categorized broadly as clastic materials and breakdown fragments.1

Clastic Sediments
Clastic material is transported into karst systems by water flow. These sediments originate from:2
* Sinking streams: Surface streams that flow directly into the cave system.2
* Surface infiltration: Soils and debris washed underground through sinkholes.23
* Caprock: Material derived from overlying sandstone and shale layers.2
* Bedrock residue: Insoluble materials left behind as the limestone bedrock dissolves.23

Once inside, the flow velocity of conduit water determines the transport and deposition of these materials, ranging from fine clays and silts to larger cobbles and boulders.2

Breakdown and Chemical Sediments
In addition to transported clastic material, caves accumulate sediments through:
* Breakdown: Blocks, slabs, and fragments that fall from the cave walls or ceilings due to structural instability.14
* Chemical precipitation: Minerals, most commonly calcite, deposited by percolating water to form speleothems.1