A Device for Prediction about the Variation of Thickness of the Ore-body

Abstract

For the purpose of explaining and interpreting the geologic structure in country rocks of "Kieslager", the writer has thought out a new method to analyse the fabric ("L-S fabric") inwoven by lineation (L) and schistosity plane (S) of the rocks. At this analysis, both lineation and schistosity plane have been plotted as a point on a stereographic projection. Because every lineation may lie on the respective schistosity plane, a plotted point of the lineation (L) must be placed on the great circle drawn 90°from another plotted point of the schistosity plane (S). Also in the "L-S fabric diagram" contoured statistically, max. L and max. S show the similar relationship.
In the diagram of country rocks which show "Beule" due to the shape of ore-body, the figure of L and S may be deformed nearly along the great circle on which the max. L and S are placed. By the manner of this deformation of the figure, the direction in which the ore-body grows either thin or thick, can be determined.
In the other kinds of deposits except "Kieslager", the "F fabric" —the small fault (slip) system along the ore-body or the fracture (joint) system controled the shape of ore-body— shows the deformation of "Beule" instead of the "L-S fabric". Also from the manner of this "Beule" deformation in the "F fabric diagram (F. F. D.)", the variation in thickness of the ore-body can be determined.