A%20soil%20profile%20is%20an%20exposure%20from%20the%20surface%20downward%20through%20a%20soil%20to%20its%20parent%20material.

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A soil profile is an exposure from the surface
downward through a soil to its parent material.
Image Martin Miller
Image NRCS
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Soil profiles generally expose three layers or
soil horizons.
Image National Cooperative Soil Survey
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The upper A horizon contains organic matter
mixed with mineral particles. Percolating water
dissolves and removes some mineral constituents
from the A horizon.
Horizon A
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Some constituents dissolved from the A horizon
are deposited below in the B horizon.
Horizon A
Horizon B
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The C horizon is the lower soil layer developed
on the underlying parent material.
Horizon A
Horizon B
Horizon C
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A mature soil profile with well developed A, B,
and C horizons takes hundreds to thousands of
years to develop.
Horizon A
Horizon B
Horizon C
Image NRCS
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