B horizon

American  

noun

Geology.

1. the subsoil in a soil profile.

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B horizon British  

noun

1. the layer of a soil profile immediately below the A horizon, containing deposits of leached material

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B horizon Scientific  

1. In ABC soil, the second and middle zone, characterized by an accumulation of soluble or suspended organic material, clay, iron, or aluminum. These materials originate in the A horizon and are transported to the B horizon through the process of eluviation. B horizons often have a blocky structure and are reddish in color due to the presence of oxidized metals.

2. Also called zone of accumulation zone of illuviation

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Etymology

Origin of B horizon

First recorded in 1935–40

Example Sentences

He had dug the trenches for the footing and got down to the B horizon in the soil where there was no organic material.

From Seattle Times