There are none. Archeology is not an experimental science which seeks to explain observed natural phenomena such as falling bodies or planetary orbits or chemical reactions. It is an observational science which seeks to describe and explain the static remains of human population and activity. People build where they build and leave behind what they leave behind and none of this is governed by natural law. Thus the archeologist is faced with the very difficult task of figuring out what a mass of material means based on his knowledge of the culture that left it and the context in which it was left.