The claim has often been made that "the geologic column is an idea, not an actual series of rock layers. Nowhere do we find the complete sequence" (Henry Morris and Gary Parker, What Is Creation Science? San Diego: Creation-Life Publ., 1987). This statement does have an element of truth, because nowhere in the world is there an unbroken record of all time from the creation of the Earth to the present. However, no such record is expected by anyone, for many reasons. Deposited layers can be later eroded away or destroyed in other ways, and drought can prevent layers from being deposited at all for long periods of time. However, the above statement is very misleading in that it insinuates that the geologic column is somehow a "figment of the evolutionist's imagination." The truth is that the geologic records all over the world are very well correlated with each other, not only with stratigraphy (i.e., which layer overlies which layer) and fossils, but with paleomagnetism, radiometric dating, and many other important factors, all of which fit together remarkably well. This does not mean that everything is completely understood (otherwise science would cease to exist), but it does mean that we have a very good handle on the stratigraphic record. Furthermore, using the criterion that Morris and Parker set for themselves, their statement is not technically true at all. They claimed the non-existence of any location where all 11 of the Phanerozoic periods of the geologic column are represented, while in fact there are now 23 such locations known, including the Williston Basin in North Dakota.