Logging Tasks
- Visit the site, tell me who was with you and who your are sending answers for (if a group).
- Looking at the ridge, does it appear to have broken though or pushed through a hole in the side?
- On the north end of the pullout, what kinds of lava do you see?
- On the south end of the pullout is it the same mix of lava types? what is the primary type
- Add a photo of you from the location or of an identifiable item (paper with trackable name). Posting a photo pulled from the internet, or photoshopped will result in instant deletion.
New test
At this location you can see the flow of lava under the road and heading east, its wource is the crater that is to your west. You can see the high hill, and make out a jagged ridge. As you drive around the park, you may assume that it is more of the a'a lava. That type of lava is like dropping a bunch of broken material and sticking it together in a large pile. As the lava rises, it splashes and cools around the edges and builds it to a higher level. Slowly the walls get taller and taller.
Failure
Eventually the wall fails, and the lava starts pouring out. It creates what is known as the big sink (the hole that is left) and the Lava Cascades that pour out. The walls of the big sink still remain. Looking like a ridgeline over the landscape.
Types of Lava
Block Lava
This type of basaltic lava forms with very few gaseous bubbles. The silica content is fairly high and the temperatures tend to be lower than other types (2012° F). Because of less gasses, it tends to have a smooth, glossy surface. It creeps slowly and is very dense
A'a
This is Hawaiin for hard on the feet. The lava flows of these have very rough and jagged survaces. It is more viscou8s than other types and flows slowly. Moving like a mass of broken rubble. The surface cools, and breaks up as it moves, then never softens again. So it is a mass of sharp, jagged edges. Those flows are pretty much impassable to those on foot, and can destroy hiking boots. The temperiatures tend to be about 2100° F
Cinders
In the early stages of a basaltic eruption, lava his highly charged with gases. As it approaches the surface and pressures drop, the gas expands raplidly, pushing the materual upward. An explosion takes place throwing it out. The lava cools rapidy and fall to the surface. Thes pieces tend to be a few mm it size to baseball size. They build up and create a cone around the volcano. The temperatures are around 2170° F
Pahoehoe
Is a smooth lava. It takes is name from the Hawaiian word for "ropy". Parhohoe lava flows are highly liquid, and flow easily. The surface of the flow cools and forms a thin crust, and the flowing lava below it drags it along, forming a layer that looks like ropes or coils. The temperatures of this are also very high 2170° F with a lower amount of gasses than cinders. Many more gas voids will be in these
Leave no Trace
Remember as you visit these sites to practice Leave No Trace. Please stay on existing trails and roads, and do not gather or take anything. We want these locations to be as good as you are seeing them for future generations. Take pictures and enjoy the locations, but leave the rocks and plants behind.
Information for this cache comes from "Geology of craters of the Moon" by Douglass Owen, and Sonja Melander; USGS geological map of the Inferno Con Quadrangle by Kuntz, Lefebvre, Champion and Skipp.