It looks like the Earth is opening up and letting out into the world what lies within. Some call it the Chthonic and in many myth it is her spirit and the elementals (the children of Gaea) that lives within her (the Otherworld) bringing back the forgotten magic of the world. The one on the left seems kind of astonished/awed (maybe a little scared) over the muchness of it all while the one on the right seems more leveled over what is happening. So basically I see Mother Earth opening up...