| AAD | Australian Antarctic Discordance |
| AADA | Australian Antarctic depth anomaly |
| AAMA | Australian Antarctic mantle anomaly |
| SEIR | Southeast Indian Ridge |
| Zone A | SEIR east of the AAD |
| Zone B | SEIR within the AAD |
| Segment B5 | The easternmost transform-bounded axial segment within the AAD. AAD segments are numbered B5 through B1 from east to west. |
| IMM | Indian (Ocean) MORB mantle (isotopically defined) |
| PMM | Pacific (Ocean) MORB mantle (isotopically defined) |
| TMM | Transitional MORB mantle |
Note: MORB = mid-ocean-ridge basalt.