They appear to be triggered by earthquakes and are accompanied by sudden winds just before they open and only for a few moments .
These often blue ( but sometimes green ) swirling mists are portals to other worlds and times .
mists appear to be triggered by earthquakes and are accompanied by sudden winds just before mists open and only for a few moments .
These often blue ( but sometimes green ) swirling mists are portals to other worlds and times .