For 100 years, the National Park Service has preserved America’s special places “for the enjoyment, education, and inspiration of this and future generations.” Celebrate its second century with the Find Your Park GeoTour that launched April 2016 and explore these geocaches placed for you by National Park Service Rangers and their partners.
geocaching.com/play/geotours/findyourpark
Getting to the cache: This EarthCache is located at the end of the Whitney Butte Trail (3.3 miles one way). The trail is well-laid out, but there are rocky sections. Be sure to take caution and watch where you are walking. The trail enters into a wilderness area, follow wilderness guidelines.
Remember that you are in a National Park Service site.
- All plant material, rocks, animals, and historical features are protected by law and may not be collected or disturbed.
- Please practice Leave No Trace
- Safety information: Although not commonly encountered, watch out for bears, mountain lions, and rattlesnakes.
- Lava Beds National Monument Visitor Center information:
- Address: 1 Indian Well HQ, Tulelake, CA 96134
- Phone Number: 530-667-8113
- Website: www.nps.gov/labe
- In an emergency: dial 911
Geological Information:
You are on the Medicine Lake Volcano, a shield volcano within the Cascade Range of which Lava Beds National Monument makes up about 10%. The Medicine Lake Volcano is half a million years old and has been erupting periodically since its birth. Over the course of the hike to the cache, you will be walking over three lava flows and coming face to face with the monument's youngest one, the Callahan Flow.
As you begin your hike, you will walk over the Basalt of Mammoth Crater, the largest lava flow in the monument, covering about 70% of the surface area. This lava flow is 36,000 years old and erupted from Mammoth Crater at the monument's southern boundary. You'll pass over another flow and then once you near the end of the trail, you will pass the older Whitney Butte off to your left and you will travel over the corresponding lava flow. Finally, you will reach the end of the trail and come to the flow you've been waiting for, the Callahan Lava Flow.
The Callahan Flow is a basaltic andesite flow that erupted from Cinder Butte ~1,180 years ago. The rough and jagged appearance of the lava flow is typical of aa (ah-ah) flows. There are two main types of lava flows, aa and pahoehoe (pa-hoy-hoy). These flows have obvious textural differences, but also have different properties such as crystal content, gas bubble concentrations, and different temperatures. Aa is rough and jagged and forms when lava is flowing quickly, allowing for heat to be lost at a faster rate and a higher viscosity (resistance to flow). Pahoehoe is a smooth and ropy, slow moving flow that can form lava tubes! Aa lava flows also tend to be thicker than pahoehoe.
Notice the size and features of this flow. What does the rock look like? Can you tell that this is an aa flow versus a pahoehoe flow?
To log this cache, send an email with the answers to the questions: Estimate the thickness of the lava flow in front of you. What other notable features can you see at this location (either of the lava flow or in your immediate surroundings)?
For more information, see our Geology Brochure and find out more information on planning your visit by visiting www.nps.gov/labe.
Approved by Patrick Taylor, Chief of Visitor Services at Lava Beds National Monument. Contact: 530-667-8113