Figure 2. Restored isopach map of the Lower Jurassic. The eroded area illustrates the irregular pattern of the Middle and Late Jurassic composite dome. Redrawn from Ziegler (1990). VG: Viking Graben; CG: Central Graben; MFG: Moray Firth Graben; SP: Sole Pit Basin; TZ: Tornquist Zone.