Groundwater flowing through certain types of rocks can produce caves or natural openings below the surface that are connected to the surface.
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To be more helpful to those 13 and anyone else... The "certain types of rocks" are those soluble in naturally slightly acidic groundwater, so are limestone (primary constituent, calcium carbonate) and gypsum (calcium sulphate).
Further, the water has to penetrate the rock formation - it oozes through the joints, bedding-planes, faults and other permeable discontinuities and eventually dissolves their wall rock enough to give discrete, stream-bearing conduits - and escape through risings (springs).
A synonym for aquifer is groundwater reservoir.
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Sand.
aquifer
The top level of groundwater in an aquifer is called the water table.
The top level of groundwater in an aquifer is called the water table.
groundwater
A synonym for aquifer is groundwater reservoir.
water.aquiferAquiferan aquifer
Aquifer.
Under the ground, in an aquifer.
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Do you mean an aquifer?I don't really get the question. Message me back.The correct answer is an aquifer.
It is called an aquifer.
An aquifer.
Sand.