| Alderman Islands(expression, name, volcano, geology) |
| Alexander Selkirk(expression, name, volcano, geology) |
| Ali Mela(expression, name, volcano, geology) |
| Alice Arm(expression, name, volcano, geology) |
| Anilao Hill(expression, name, volcano, geology) |
| Anjouan Island(expression, name, volcano, geology) |
| Antipodes Island(expression, name, volcano, geology) |
| Apagado(noun, name, volcano, geology) |
| Apuseni Mountains(expression, name, volcano, geology) |
| Ata Volcanic Complex(expression, name, volcano, geology) |
| Atherton Volcanic Province(expression, name, volcano, geology) |
| Auca Mahuida Volcanic Field(expression, name, volcano, geology) |
| Avos' Rocks(expression, name, volcano, geology) |
| Axial Chain(expression, name, volcano, geology) |
| Azrou Volcanic Field(expression, name, volcano, geology) |
| Azufre(noun, name, volcano, geology) |
| Bakony-Balaton Highland(expression, name, volcano, geology) |
| Bald Knoll(expression, name, volcano, geology) |
| Ban Chay(expression, name, volcano, geology) |
| Ban Chiang Khian(expression, name, volcano, geology) |