Green Pond Marsh and 50 percent to 90 percent sand and have loamy sand or sandy loam textures." The work describes hydrologic soil group C as having "moderately high runoff potential when thoroughly wet. Water transmission through the soil is somewhat restricted. Group c soils typically have between 20 percent and 40 percent clay and less than 50 percent sand and have loam, sandy clay loam, clay loam and silty clay loam textures." Green Pond Marsh is in a section of Northampton County with karst geological features. Karst geology manifests itself on topographic maps with closed, semi-closed, or linear depressions. The depressions are
Dilatancy (granular material) On the other hand, when a granular material starts in a very loose state it may continuously compact instead of dilating under shear. A sample of a material is called dilative if its volume increases with increasing shear and contractive if the volume decreases with increasing shear. Dilatancy is a common feature of the soils and sands. Its effect can be seen when the wet sand around the foot of a person walking on beach appears to dry up. The deformation caused by the foot expands the sand under it and the water in the sand moves to fill the