What is a common permeability characteristic of lacustrine deposits?

Lacustrine deposits are sediments that have settled in lake environments, often consisting of various materials ranging from fine silts and clays to coarser materials. A key characteristic of lacustrine deposits is their very slow permeability rates, especially when they have a significant clay component. This is because clay particles are very small and tend to pack tightly together, creating a dense structure that inhibits water flow.

Very slow permeability may also lead to conditions where the deposits can become effectively impervious, especially if they contain a high proportion of cohesive materials. This characteristic is important for understanding groundwater movement and the behavior of water in soil when it comes to construction, agriculture, and environmental management. Thus, lacustrine deposits are often associated with slow-draining conditions, making them relevant in various engineering and hydrological contexts.