Almost 500 million years ago, during the Ordovician period of the Paleozoic Era, something amazing happened in our area. Warm shallow seas covered the Pikes Peak region of Colorado, and were home to an abundant shell life. As the sea creatures died, their shells fell to the sea floor. Broken up shells accumulated over millions of years. These many layers of shells eventually squeezed, compacted, and cemented together into solid rock that we now call limestone.
Fast forward to 70 million years ago. The warm shallow seas started to recede and dry, lifting the limestone and forming what is now known as the Rocky Mountain region. Approximately 4 – 7 million years ago, the limestone fell below the water table. Rainwater mixed with carbon dioxide, forming a weak carbonic acid. This acid solution slowly ate away at the limestone, leaving behind small pockets that filled with water. As more limestone dissolved over many thousands of years, pockets grew into passageways. Passageways grew into rooms, rooms grew into caverns, and the caves were slowly formed.
As the water table continued to drop below the cave system, air filled the passageways and rooms, eventually forming stunning speleothems. Stalactites formed within the caves when calcium carbonate-rich water would form on a cave’s ceiling and start to drip. Every droplet that formed on the ceiling would crystallize into a calcite ring. Over many thousands of years, this slow process would form beautiful icicle-like stalactites. Underneath the dripping stalactites, stump-shaped stalagmites would slowly form from the calcium carbonate crystals being built up on the cave floor.
One of the most amazing features in caverns at Cave of the Winds Mountain Park is the flowstone. Flowstone, also called frozen waterfalls, are curtain-like formations that gently flow along the side of a cavern or passage. These areas were formed by mineral-rich water flowing down the cave wall for thousands of years, leaving calcite behind.