A Design of Personal Geological Outcrop(Field Note) Database (part 2 )

On the Expression Method of the Stratigraphy

Abstract

Description of the outcrop is important in the geological survey. The arrangement of the observation result becomes a big burden as the survey goes on. For this reason, it is desirable that database has not only outcrop lists but also have functions which construct the geological structure of the investigation area from outcrop.
The author propose the stratigraphical graph and the stratigraphical formula as the descriptive method of outcrop data on the outcrop database. A directed labeled graph is applied to this graph;, vertexes of the graph correspond to layers and arcs of the graph correspond to the contact relations. Each arc of the graph connects from the lower layer to upper layer. The label of vertex is the layer name, and the label of arc is the name of contact relation. The name of the layer and the contact relation are related to the description of the layer and the contact relation under the binary relation respectively.
The stratigraphical formula expresses the stratigraphical graph with a set form: This formula expresses the contact relation of the two layers with the form (lower layer unit)(relation unit)(upper layer unit), where layer units are represented by layer names and contact units are by symbols. With this formula, we are able to express the data outcrop data uniformly, including the case that boundary of layers is unknown and the case that the condition of boundary is estimated from neighboring outcrops. The stratigraphy of the investigation area can be established through operation of the stratigraphical formulae of outcrop. The author proposed the algorithm of this operation.