| Acquasparta(noun, name, volcano, geology) |
| Adachi(noun, name, volcano, geology) |
| Adagdak(noun, name, volcano, geology) |
| Adamozhets(noun, name, volcano, geology) |
| Aegina(noun, name, volcano, geology) |
| Aguajito(noun, name, volcano, geology) |
| Aguas Delgadas(expression, name, volcano, geology) |
| Ahon(noun, name, volcano, geology) |
| Aira Caldera(expression, name, volcano, geology) |
| Aird Hills(expression, name, volcano, geology) |
| Aitutaki(noun, name, volcano, geology) |
| Aizu Nunobiki(expression, name, volcano, geology) |
| Akaigawa(noun, name, volcano, geology) |
| Akhuryan Valley(expression, name, volcano, geology) |
| Albuquerque(noun, name, volcano, geology) |
| Aldama Volcanic Field(expression, name, volcano, geology) |
| Alderman Islands(expression, name, volcano, geology) |
| Alexander Selkirk(expression, name, volcano, geology) |
| Ali Mela(expression, name, volcano, geology) |
| Alice Arm(expression, name, volcano, geology) |