Building of precision position and elevation networks

The building is described of a local network for evaluating the tectonic stability of a selected area and assessing the development of horizontal and vertical displacements of control points and for high precision layout work. A draft is presented of the concept and the principles of the local network listing also conditions for reducing systematic errors in the network. The building is also described of an elevation point field which is determined by accurate trigonometric measurement of the differences in elevations and altitudes in the local network. (E.J.). 4 refs