Pleistocene Series, worldwide division of rocks deposited during the Pleistocene Epoch (2.6 million to 11,700 years ago).
Waterberg Series, also called Waterberg System, major division of rocks in southern Africa.
Werner's quadripartite division of rocks in southern Germany was applied well into the second decade of the 19th century.
Grand Canyon Series, major division of rocks in northern Arizona dating from Precambrian time (about 3.8 billion to 540 million years ago).
Paleocene Epoch, also spelled Palaeocene Epoch, first major worldwide division of rocks and time of the Paleogene Period, spanning the interval between 66 million and 56 million years ago.
Coutchiching Series, division of rocks in the region of northern Minnesota and Ontario radiometrically dated to have formed about 2.6 billion years ago during Precambrian Time (the Precambrian lasted from 3.96 billion to 540 million years ago).
Hornfels facies, a major division of metamorphic rocks (rocks that form by contact metamorphism in the inner parts of the contact zone around igneous intrusions).
Felsic and mafic rocks, division of igneous rocks on the basis of their silica content.
Graptolites have proved to be very useful for the stratigraphic correlation of widely separated rock units and for the finer division of Lower Paleozoic rock units (Cambrian to Devonian); examples include the genera Climacograptus, Clonograptus, Didymograptus, Diplograptus, Monograptus, Phyllograptus, and Tetragraptus.
Based on this a simple, qualitative division of the rock masses is presented, which together with the influence of stresses, ground water and dimension of the excavation, is used to find the probable behaviour.
