Going deep underground!
Apr 21, 2009
|The northeastern corner of California is high desert. On entering the park from the north the land looks barren, covered by clumps of sagebrush but as you head south and higher up the vegetation gradually changes to more junipers and eventually pine forests. But deep underground in this area is a completely different world. There unfolds the legacy of Northern California’s volcanic activity.
Within the Lava Beds National Monument there are more than 300 lava tube caves. Lava is hot when it pours from a volcano- about 1,800ºF. The outer edges and surface of the flow cool rapidly and begin to harden. This outside shell acts as insulating material while the rest of the flow beneath it remains hot and fast-moving. The flow continues on. When the eruption stops and the river of lava drains, a tunnel or tube -the outer shell – is left. (National Park information leaflet) Many of the tubes in the park were formed over 30,000 years ago after an eruption at Mammoth Crater, south of the park.
We were able to visit several of the lava tube caves which had been first developed for public access by the Civilian Conservation Corps in the 1930’s and 40’s. However before we explored the caves we borrowed flashlights at the visitor center and donned our bicycle helmets (at last we found a second use for them!) to protect our heads.
Our first lava cave was the Mushpot Cave which was recommended as an introductory cave. This cave had low lights and interpretive signs explaining the formations.
Our next stop was the Indian Well Cave. Here we walked down a wooden walkway into a very high ceiling tube and found some rather unusual ice formations at the bottom. It was certainly cold within this cave!
On our way to the next cave we stopped at what was called the Natural Bridge. Here we found a place where the roof of a lava tube had collapsed. The short trail allowed us to see where a number of lava tubes had been.
At the Sentinel Lava tube cave we were able to walk a mile through the cave. This was the only developed cave with two entrances. Here we certainly need our flashlights and passed a number of interesting features such as lavacicles on the ceiling, larva tubes on top of one another, curbing which marked former flow levels to name just a few. It was certainly dark within the cave and glad to say the flashlights worked well.
Our final cave we explored was Skull Cave. This cave was named for the bones of antelope and mountain goats, bighorn sheep skulls and two human skeletons discovered inside (now removed!) The cave is a remnant of two very large lava tubes, one on top of the other. This allows cold winter air to be trapped inside and creates a year round ice floor at the lower level. However the floor was very difficult to distinguish due to stones and dust and was going to be cleaned!
After visiting the caves we drove through the rest of the park which had been the site of a major battle between the U.S. Army and the Modoc Indians in 1872 when the Indians were being forced onto reservations. Initially the Modocs drove off the troops and sought safety in the lava beds where they stayed for five months. Due to the army blocking off their water supply and further bloodshed the Modocs surrendered.
We also continued to see the legacy left by the Civilian Conservation Corps. Although many Americans do not recognise it Roosevelt’s New Deal which included the establishment of the Civilian Conservation Corps at the time of the Great Depression resulted in a huge legacy of parks, trails, and buildings etc which are still being used today across the USA.