Boundaries: Origin, Form, Function, and Dispute

Classify a boundary twice: by FORM and by ORIGIN

By form — what the line follows on the ground. Physical (natural) boundaries follow rivers, mountain crests or deserts. Geometric boundaries follow straight lines of latitude or longitude and ignore the landscape. Cultural boundaries follow a language or religion divide.

By origin — when the line was drawn relative to settlement. An antecedent boundary was drawn before the area was substantially settled. A subsequent boundary was drawn after settlement and adjusted to fit the cultural pattern. A superimposed boundary was forced onto an existing settled cultural pattern by an outside power, cutting through it. A relict boundary no longer functions but is still visible in the landscape. A consequent boundary is the subtype of subsequent boundary that follows a cultural divide directly.

The four steps that make a line real

Definition is the legal text in a treaty. Delimitation is drawing it on a map. Demarcation is marking it on the ground with fences, pillars or posts. Administration is how it is policed and crossed day to day. Most of the world's boundaries are defined and delimited but never fully demarcated.

Four kinds of dispute

A definitional dispute is about what the treaty language means. A locational dispute is about where the line actually sits — a common outcome when the boundary follows a river that has since shifted its channel. An operational dispute is about how the boundary is managed: crossing, migration, policing. An allocational dispute is about a resource that straddles the line, such as an oil or gas field or an aquifer.

At sea, the UNCLOS framework gives a 12-nautical-mile territorial sea and a 200-nautical-mile exclusive economic zone. Where claims overlap, the usual technique is a median line drawn equidistant from the two coasts.