Quicksand is a colloid hydrogel consisting of fine granular material (such as sand), clay, and water. It behaves like a liquid when agitated but can trap objects due to its inability to support weight. Quicksand is significant in sedimentology and soil mechanics for understanding fluidized sedimentary layers and their impact on construction and land stability.
Source Dunn, I. S., Anderson, L. R., & Kiefer, F. W. (1980). “Fundamentals of Geotechnical Analysis.” Wiley.