contour line on map connecting points of equal stratigraphic thickness
Contour line Various geological data are rendered as contour maps in structural geology, sedimentology, stratigraphy and economic geology. Contour maps are used to show the below ground surface of geologic strata, fault surfaces (especially low angle thrust faults) and unconformities. Isopach maps use isopachs (lines of equal thickness) to illustrate variations in thickness of geologic units.
China–Nepal border The line extends between two tripoints China–Nepal–India. The tripoint in the west is in the Nepalese district of Mahakali Zone. The tripoint in the east is in the region of Mechi.