Definition - What does Isopach Map mean?
Isopach map is a map used to delineate the variations in thickness within a layer, tubular unit or stratum. Isopachs are referred to as the contour lines with equal thickness over a particular area. These maps are used in the stratigraphy, structural geology, volcanology, petroleum geology and sedimentology. This type of mapping is used to predetermine the drilling depths of wells and locate the structures buried in the regions in which the formations commonly become thinner over certain structural crests.
Petropedia explains Isopach Map
Isopach Maps are similar to the other thickness maps known as isochore maps; however, they describe distinct methods for displaying the variations in thickness within a layer. The only difference between the two types of thickness maps is that the Isopach Maps exhibit the equal thickness in layers in which the thickness is measured perpendicular to the boundaries of the layer whereas the isochore thickness is vertically measured. The Isopachs which make up the map, exhibit the strategic thickness of the rock unit opposite to its vertical thickness.