In the Carlsbad Caverns today about 10 per cent of the formations are "alive". Water is seeping in around them and working its wonders. It is this presence of water that gives them the polished, radiant look.
When the water no longer reaches the formations, they "die", i.e., they no longer continue to grow. They lose their sheen and lustre and take on a powdery appearance.
Geologists differentiate the two primary effects of seeping water in the creation of the formations in caves. Those that are created by water dripping from above, as in the case with stalactites and stalagmites, are referred to as dripstone formations. Those created by the flowing of water over a surface are called flowstone formations. In some rooms of the cave, formations made of flowstone are quite abundant. This is to be found mostly on the floors of the rooms, or on walls where a large volume of water is present. These formations have been referred to as masses which resemble ice that forms on a cold winter's day near a stream of water. Others have described them as "cascades frozen in stone."
An additional phase of the cave's development has been described by geologists as the period of collapse. During the centuries when the entire area was saturated with water, limestone blocks on walls and ceilings were weakened by solution, later to crash to the floor, leaving the room larger than ever. This collapsing continued after the cave became "dry" but ended once stability was achieved. Park naturalists tell us no rock has fallen within the cave for thousands of years.
So ends the first stage of the history of the great Carlsbad Caverns, their gradual growth and formation over periods of millions of years. Man was still centuries away when their beauties were being created. But were other forms of life inhabiting them?
2
Life Enters the Caverns
At the time the limestone beds were beginning to crack, which we noted was some 60,000,000 million years ago, the huge reptiles and other prehistoric animals were playing hide and seek on the surface above the site of the developing Caverns. At that time the cave hadn't yet been formed—the underground seepage of water was just beginning to find the crevices below the gypsum and rock salt and begin its erosion which was to continue slowly for so many centuries.
Recent forms of life seem to have a more or less direct bearing on the bat, and scientists remain quiet on what forms of life, if any, used the cave for their domicile between the earliest times and the arrival of the bat.
At least, the nocturnal creature is a sure resident, for he still makes his home there, and in numbers running into the millions.
But when did the bat first inhabit the cave? That is difficult to answer, except to say that it was several thousands of years ago.