Platform (geology)
In geology, platform is a craton covered with sediments. It can be classified into the following groups: a "protoplatform" of metamorphosed sediments at the bottom, a "quasiplatform" of slightly deformed sediments, a "cataplatform", and an "orthoplatform" at the top. The Mesoproterozoic Jotnian sediments of the Geology of the [Baltic Sea|Baltic area] are examples of a "quasiplatform". The post-Ordovician rocks of the South American Platform are examples of an orthoplatform.