Soils are often described as structureless, spheroidal, blocky or platy: Structureless soils have no observable aggregation and no definite arrangement of the soil particles. ... Clay soils may also be described as structureless when the particles form a massive structure with no small aggregates within.

What causes platy soil?

Platy structure is usually found in subsurface soils that have been subject to leaching or compaction by animals or machinery. The plates can be separated with a little effort by prying the horizontal layers with a pen knife.

Where is prismatic soil found?

They are commonly found in the B-horizon where clay has accumulated; 3 Prismatic and columnar structures are soil particles which have formed into vertical columns or pillars separated by miniature, but definite, vertical cracks.