Changes

===Vertical and horizontal scale===

===Vertical and horizontal scale===

To show significant details of stratigraphic variation, it is usually necessary to exaggerate the vertical scale with respect to the horizontal scale on a stratigraphic cross section. It is important to realize the effect that this distortion has on reservoir geometry and angular relationships of geological surfaces. The small angular differences between stratigraphic horizons that account for thickness variations are strongly exaggerated in such a section. The apparent dip of a bed in a vertically exaggerated cross section is related to true dip by the following equation:<ref name=pt06r72>Langstaff, C. S., Morrill, D. 1981, Geologic Cross Sections: Boston, MA, IHRDC, 108 p.</ref>

To show significant details of stratigraphic variation, it is usually necessary to exaggerate the vertical scale with respect to the horizontal scale on a stratigraphic cross section. It is important to realize the effect that this distortion has on reservoir geometry and angular relationships of geological surfaces. The small angular differences between stratigraphic horizons that account for thickness variations are strongly exaggerated in such a section. The apparent dip of a bed in a vertically exaggerated cross section is related to true dip by the following equation:<ref name=pt06r72>Langstaff, C. S., and D. Morrill, 1981, Geologic Cross Sections: Boston, MA, IHRDC, 108 p.</ref>

:<math>\tan \delta_{\rm E} = V \tan \delta</math>

:<math>\tan \delta_{\rm E} = V \tan \delta</math>