Carlsbad Caverns is one of the most spectacular sights New Mexico has to offer and a unique adventure for anyone who wants to feel like they are exploring a cave from the comfort of a paved walkway. Designated as a National Park in 1930, and a UNESCO World Heritage Site in 1995, Carlsbad Caverns has proven to be an invaluable natural resource visited by hundreds of thousands of people each year. To log this earthcache, you will need to read the information and answer the questions below. Answers can be emailed to the cache owner using the features included on geocaching.com. You do not need to wait for a reply in order to log the earthcache, but if I do not receive your answers within a few days your log may be subject to deletion. Please do not include any answers in your logs. These will be deleted quickly. The cache is wheelchair accessible and can be accessed either by hiking down the Natural Entrance trail, or taking the elevator directly to the Big Room. The information needed to log this earthcache can be found without venturing to the part of the Big Room trail that is not wheelchair accessible, though I recommend walking the full Big Room and Natural Entrance trails if you are able because there are so many unique features to see. A fee is required to visit the Caverns which is highly variable depending on your situation. Fee information can be found on the National Park Service website. Please obey all park rules and safety regulations. These rules are in place not only for your safety but for the preservation of our natural resources. There is absolutely no reason to break any of the rules to find this cache. Everything you need can be observed from the paved trail without touching anything.
**At this time, Carlsbad Caverns is only allowing a limited number of people per day into the cavern. The cavern opens at 8am and the last ticket is sold at 2:15 pm. It is recommended that you arrive earlier, particularly on more popular travel days.**
Carlsbad Caverns began to form millions of years ago. It is a limestone cavern much like many other major cave systems in the United States, but was formed under more unusual circumstances. Around 265 million years ago the area in which Carlsbad is located was a large reef known as “The Capitan Reef.” The reef created a thick layer of limestone over 400 miles long and about 1,800 feet thick. This reef was fully buried during the Permian age, but during the past 20 million years the reef was uplifted by faulting and stresses. The uplifting of this limestone layer played a crucial role in the formation of Carlsbad Caverns. Limestone is an easily dissolvable mineral and can be dissolved even by weak acids. Many well-known limestone caves are created by the slow migration of carbonic acid from rainwater slowly moving downwards carving out cave networks. Carlsbad was formed through a different process using sulfuric acid.
The Capitan Reef area contains numerous oil deposits as well, which allows for the presence of hydrogen sulfide. Hydrogen sulfide migrated through the ground until it met up with rainwater moving in to create the underground water table. When the oxygen from the water combined with the hydrogen sulfide already underground, the result was the formation of sulfuric acid. Sulfuric acid is far more aggressive at dissolving limestone, and as the sulfuric acid moved through cracks in the limestone, cave passages began to form. The slow uplifting of the Capitan Reef caused the water table to lower its position relative to the surface, and Carlsbad Caverns was dissolved into place. As these processes took place speleothems began to grow. A speleothem is another term for cave formation. Some examples found in Carlsbad caverns include stalagmites, stalactites, columns, soda straws, draperies, popcorn, and flowstone. Speleothems are formed through a variety of processes and in some areas of the cave they can be observed as ongoing today.
The Big Room of Carlsbad Caverns is the largest known cave chamber by volume in North America. The Big Room is located approximately 750 feet underground. Inside, you will find some of the largest speleothems in the cave along with numerous smaller formations that create intricately decorated passages. To log this cache, you will need to visit some of the largest speleothems in the entire cave!
In order to log this cache, you must journey to The Big Room. As you walk along the trail you will notice informational signs that direct you to some of the most notable points in the cave. You will need to find the sign titled “Drip by Drip” along the wheelchair-accessible portion of the trail. The sign references a “trio” of the largest of one type of speleothem in the cave. Since cell service and GPS signal are unavailable in the cave, I recommend saving these questions in some way that can be viewed offline. Using the information on the sign, and your observation skills, answer the following questions:
- The sign describes the process by which these speleothems formed. Now use your eyes and ears to observe what is going on around you. Is the process still taking place today? How do you know?
- The sign states that these speleothems were formed quickly. Looking at the three formations, what do you think would have happened if they formed a little more slowly? (If you need a hint the sign can help)
- On the large speleothem nearest you, you can see an intricate network of smaller speleothems. Describe these smaller formations within the formation. Why do you think this occurred?
*All the information on this page was learned from the National Park Service website and credit should be given as such.
**This cache was created with permission of Carlsbad Caverns National Park.