A soil that contains a significant proportion of coarse material; 20 to 80 percent of the particles are greater than coarse sand (0.08 inches or 2 millimeters), with the remainder finer than 0.08 inches or 2 millimeters.
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Glossary
Debris
Debris Fan
A deposit of debris-sized material that is known or reasonably inferred to be emplaced by mass wasting processes and has a distinctive lobe, fan, or coalescing fan shape. Debris fan can include colluvial and alluvial components.
Debris Flow
A type of slope movement in which the displaced mass is composed of debris and the water content in the displaced mass is sufficient for the material to liquefy and resemble a viscous fluid.
Debris Slide
A slope movement initiated by slippage along a well-defined failure surface that is usually planar or curvi-planar, in which the displaced mass is composed of debris. Slides are divided into two classes, rotational and translational. Slides usually consist of displaced and deformed blocks of material.
Deformation
A general term for the process of folding, faulting, shearing, compression, or extension of the rocks as a result of various Earth forces.
Degradation
The destruction of complex natural environments.
Diabase
A dark, medium-grained, plutonic igneous rock, consisting mostly of calcium-rich feldspar and mafic minerals, that is chemically similar to basalt.
Dike
A tabular igneous intrusion that cuts across the bedding or foliation of the rock surrounding it.
Disturbance
A relatively discrete event in time that disrupts ecosystem, community, or population structure and changes resources, substrate availability, or the physical environment.
Dolomite
A common white or colorless rock-forming mineral, calcium magnesium carbonate; also a rock composed of this mineral; adj.: dolomitic.
Dunite
An ultramafic igneous intrusive rock composed primarily of the mineral olivine.