Lassen Park, in eastern California - one of a number of volcano-related places. It's all the fault of reckless driving by the Pacific Plate, which keeps bumping over into the North American plate, trying to slide underneath it, and causing volcanic eruptions and such.
Mt Lassen - looks peaceful...
In this particular case, the eruption happened on several days in 1915. The area not being that densely populated, few were killed, but it did impress people a lot.
We climbed a nearby hill,
A lot of trees had this same curious kind of bend to them - never did figure out why. Like in their youth they suddenly got bent over at about 15 degrees and then allowed to grow straight again.
Mt Lassen - looks peaceful...In this particular case, the eruption happened on several days in 1915. The area not being that densely populated, few were killed, but it did impress people a lot.
We climbed a nearby hill,
A lot of trees had this same curious kind of bend to them - never did figure out why. Like in their youth they suddenly got bent over at about 15 degrees and then allowed to grow straight again. Sometimes they're on a hillside, sometimes not.
On to another - Lava Beds National Monument:
A lava cave. When a lot of lava flows out of a volcano, it may erupt suddenly and throw things all over the place, or it may ooze out more slowly and flow away downhill. That's what happened at Lava Beds. Then, the outside can cool off while the lava inside is still so hot it wants to flow. If the lava stops flowing out of the volcano, all the lava inside may drain away, leaving only the outside shell, a lava tube.
Some of these caves are pretty extensive. Then, as in limestone caves, water can carry minerals into the cave and then evaporate, leaving the minerals - notice the melted-wax effect.
Beautiful flowers
The Indians who lived here would spend time in the caves, especially in the winter, and paint or incise pictures.
Nobody seems to have any idea what most of them represented - not even the modern-day Indians.
A lava cave. When a lot of lava flows out of a volcano, it may erupt suddenly and throw things all over the place, or it may ooze out more slowly and flow away downhill. That's what happened at Lava Beds. Then, the outside can cool off while the lava inside is still so hot it wants to flow. If the lava stops flowing out of the volcano, all the lava inside may drain away, leaving only the outside shell, a lava tube.
Some of these caves are pretty extensive. Then, as in limestone caves, water can carry minerals into the cave and then evaporate, leaving the minerals - notice the melted-wax effect.
Beautiful flowers
The Indians who lived here would spend time in the caves, especially in the winter, and paint or incise pictures.
Nobody seems to have any idea what most of them represented - not even the modern-day Indians.
Tule Lake, in northern California. A big, very flat lake; this part is a wildlife refuge.
They had a small but really good museum at the Refuge:
Birds of Prey, with prey - telling it like it is
Like, these guys make their living by killing things (although if they come upon something that's already dead, that's okay too).
A flock of geese - very realistic
Jet contrails
Captain Jack's Stronghold, near Tule Lake. Tule lake used to be huge, but the settlers wanted to drain most of it and farm it. As usual, the Modoc Indians resisted (as usual, they lost in the end).
Captain Jack chose this place, in the middle of the lava beds, to make his stand. The ground looks pretty flat from a distance...
But once into the field, there are lots of 5,10,15 foot-high ramparts. They Indians held out for several days, killing a number of soldiers and losing almost none, until the cavalry cut them off from their water supply and they had to retreat.
Captain Jack's cave.
A shrine of sorts - some fairly valuable items here, pocket-knives, coins, items of clothing etc.
Near by, Petroglyph Point. In centuries past, Tule Lake (then called Lake Modoc) came halfway up this cliff and it was accessible by canoe; Indians left a lot of petroglyphs high up on the side. Now it's many feet in the air.
Captain Jack chose this place, in the middle of the lava beds, to make his stand. The ground looks pretty flat from a distance...
But once into the field, there are lots of 5,10,15 foot-high ramparts. They Indians held out for several days, killing a number of soldiers and losing almost none, until the cavalry cut them off from their water supply and they had to retreat.
Captain Jack's cave.
A shrine of sorts - some fairly valuable items here, pocket-knives, coins, items of clothing etc.
Near by, Petroglyph Point. In centuries past, Tule Lake (then called Lake Modoc) came halfway up this cliff and it was accessible by canoe; Indians left a lot of petroglyphs high up on the side. Now it's many feet in the air.
Bird nesting places
Some of the petroglyphs. As with the ones in the caves, nobody knows exactly what they mean (if anything. Maybe they are just Art).
Nearby, Fleener Chimneys. These Chimneys were the result of very slow ouflow of lava which built up several hollow towers. When you get to the top and look down, they ae indeed hollow, one for 50' down. You also see plaintive signs asking people please please not to throw garbage down them, since that sort of spoils the effect. 
A piece of lava crust, about three inches thick
Crater Lake - A lake right in the crater of an ancient volcano. We got there on June 16, which as it turned out, is rushiung the season. They'd just opened the park two days before; most of the roads and trails were still snow-covered...
This was called the Annie Creek Trail.
Fumaroles:
Very strange-looking structures.
The general idea behind fumaroles is that when a volcano erupts, sometimes reservoirs of gas erupt all in one place, drilling a hole thru the molten lava to do so. In the process, the gases heat the edges of the hole so hot the lava there turns into a different, harder rock. So when the rest of the stone is eroded away along with the land in general, this part stays.
Outside the park: a series of trees had some really weird galls: 
This one looks downright spooky:
Some of the petroglyphs. As with the ones in the caves, nobody knows exactly what they mean (if anything. Maybe they are just Art).
Nearby, Fleener Chimneys. These Chimneys were the result of very slow ouflow of lava which built up several hollow towers. When you get to the top and look down, they ae indeed hollow, one for 50' down. You also see plaintive signs asking people please please not to throw garbage down them, since that sort of spoils the effect. 
A piece of lava crust, about three inches thick
Crater Lake - A lake right in the crater of an ancient volcano. We got there on June 16, which as it turned out, is rushiung the season. They'd just opened the park two days before; most of the roads and trails were still snow-covered...
This was called the Annie Creek Trail.
Fumaroles:
Very strange-looking structures.
The general idea behind fumaroles is that when a volcano erupts, sometimes reservoirs of gas erupt all in one place, drilling a hole thru the molten lava to do so. In the process, the gases heat the edges of the hole so hot the lava there turns into a different, harder rock. So when the rest of the stone is eroded away along with the land in general, this part stays.
Outside the park: a series of trees had some really weird galls: 
This one looks downright spooky:
And then, on to Newberry Volcanic Park. One kind of lava, called pumice, has a lot of dissolved gas in it; when it comes out into the air, the pressure is relieved and the gas becomes vapor. So it's so full of holes it can actually float...
A lava bomb: a lump of molten rock gets thrown so high into the air that it tumbles around and cools and hardens before it gets back to the ground. Fairly rare, but interesting.
A lava bomb: a lump of molten rock gets thrown so high into the air that it tumbles around and cools and hardens before it gets back to the ground. Fairly rare, but interesting.All about silica, which makes up a lot of most rocks. When the molten silica rocks have a chance to crystallize, we get minerals of various sorts. When they cool fast, without having a chance to crystallize, we get glasses.
one kind of which is obsidian:
Newberry Volcanic Park features a Lava Flow which is very rich in obsidian:
It turns out to be very hard for anything at all to grow in. I don't know what this tree's secret was...
The obsidian is hard to pick out from this picture; when you see it, it's very smooth and shiny, and very sharp-edged!
Obsidian was very valuable to the Indians: if flaked off just right, it gives cutting edges of whatever shape you want. A certain amount of mythology is bound to grow up around something like this.
According to a sign here, a geologist was having open-heart surgery and the surgical team did part of the cutting with obsidian blades and the rest with traditional surgical steel ones. The cuts made with the obsidian were much cleaner - an obsidian blade can have an edge one molecule thick - and healed quicker than those made with the steel blades.
Ed and Barbara Eckelmeyer were out here for their daughter Kirsten's graduation from U of Oregon, and we went one day to Glass Butte, Oregon to look for obsidian.
In National Parks you can't take anything at all away; in National Forests, which are officially multiple-use, you may be allowed to. This was Bureau of Land Management land; the rule was you could take no more than 200 lbs per person, per day. Unfortunately, the airline baggage people were a little less generous about how much Barb and Ed could fly back with. But we got several very nice pieces.
one kind of which is obsidian:
Newberry Volcanic Park features a Lava Flow which is very rich in obsidian:
It turns out to be very hard for anything at all to grow in. I don't know what this tree's secret was...
The obsidian is hard to pick out from this picture; when you see it, it's very smooth and shiny, and very sharp-edged!
Obsidian was very valuable to the Indians: if flaked off just right, it gives cutting edges of whatever shape you want. A certain amount of mythology is bound to grow up around something like this.According to a sign here, a geologist was having open-heart surgery and the surgical team did part of the cutting with obsidian blades and the rest with traditional surgical steel ones. The cuts made with the obsidian were much cleaner - an obsidian blade can have an edge one molecule thick - and healed quicker than those made with the steel blades.
Nearby Indian tribes would journey several days, in the winter, to get pieces of obsidian for use or trading. An Indian would get one hunk and carry it around. When he needed a tool, he would get a piece of wood and 'flake' off the piece he needed - sort of a multipurpose tool kit.
In National Parks you can't take anything at all away; in National Forests, which are officially multiple-use, you may be allowed to. This was Bureau of Land Management land; the rule was you could take no more than 200 lbs per person, per day. Unfortunately, the airline baggage people were a little less generous about how much Barb and Ed could fly back with. But we got several very nice pieces.
It's a little hard to tell, but this is all obsidian. You have to be careful with it; it's very sharp.
On the way back, someone had this in his field. All sheet steel.
