On the physical and identification properties of a slightly organic deposit

The deposit of Baixo Mondego, which is one of the most important Portuguese deposits of soft soils, exhibits quite uncommon physical and identification proper-ties in its natural state. This paper presents the most relevant features of the soils' natural physical and plasticity characteristics, highlighting some inconsistencies on the soils' behaviour, and points out the organic matter as the main factor responsible for the high variability and unusual magnitude of almost every physical property, and also for the unusually high plasticity. The results contribute to understanding the behaviour of slightly organic soft deposits and yield information on the use of correlations based on data from inorganic soils, which may give misleading conclusions.