The lowest part in the soil profile is known as "bedrock". Bedrock is the solid rock layer that is located underneath all the other soil layers. It is made up of consolidated rock and is typically composed of minerals such as granite, limestone, or basalt. Bedrock is the base upon which all other soil layers are formed, and it is an important factor in determining the fertility and composition of the soil. The depth of the bedrock layer can vary depending on the location, with some areas having shallow bedrock and others having deep bedrock.