Future urban areas are new greenfield developments and typically managed by the ACT Suburban Land Agency. Offsets are often found adjacent to these areas. Images from ACTmapi showing the areas.
Environmental offsets and Suburban Land Agency (SLA) areas are often side-by-side. Below you can find screenshots from ACTmapi with SLA and offset areas labelled accordingly. The thick yellow lines are the borders of the suburbs. You may see squiggly thin yellow lines, if you look carefully. These are bike paths.
Meaning of offsetPlanning and Development Act 2007, pages 85
In this Act:
offset, for a development that is likely to have a significant adverse environmental impact on a protected matter, means environmental compensation for the likely impact