Dictionary:Isopach

{{#category_index:I|isopach}} 1. A contour which denotes points of equal thickness of a rock type, formation, group of formations, etc. 2. Isotime, a contour which denotes points of equal difference in seismic arrival times for two reflection events, thus indicating constant thickness if the velocity is constant. 3. A contour denoting equal vertical distance, not necessarily corrected for the dip of the bedding.