Getting Under the Skin of a Volcano: Travels in Lava Beds National Monument

What in the world is going on here?? What are these spikes coming out of the ceiling? Is it some kind of deadly trap for Indiana Jones or Lara Croft? Well, no, but they'll hurt like the dickens if you try exploring them without a hardhat. In some of the previous posts in this short series we explored the deep heart of the magma chamber beneath a volcano, and we went both on and above Mt. Shasta to see the dramatic exterior of a volcano. Today we burrow under the skin of a volcano.

Medicine Lake Highland is the biggest volcano in California. It may be barely half as high as Mt. Shasta, but it makes up for the height deficit with broad gentle slopes, giving it a volume of around 130 cubic miles, compared to about 85 for Mt. Shasta. It is classed as a shield or "shield-type" volcano, composed largely of basalt, but with varying amounts of andesite and rhyolite. As such, it displays a wide variety of volcanic phenomena, not the least of which is a dizzying array of lava tubes. A flank of the volcano is preserved as Lava Beds National Monument, and the park has within its borders the highest concentration of lava tubes in the country, if not the world. More than 700 individual caves are known at Lava Beds with a total length of more than 70 miles.

How do lava tubes form? The picture above shows an active lava flow at Pu'u'o'o Crater on the Kilauea volcano on the Big Island of Hawai'i in 2009. The scale in this aerial view is difficult to discern but the skylight (where the red lava is visible) is probably 30 feet across. The tubes develop when river-like lava flows crust over. The lava continues to flow just beneath the surface, sometimes for many miles, being insulated by the overlying crust. The flow in the picture above flowed seven miles to the shoreline and was only a few tens of degrees cooler than it was when it emerged at the vent of Pu'u'o'o. When the eruption ends, the lava drains from the tubes.

The tubes can be quite complex, with bifurcating passageways and multiple levels (one particularly complex cave is called the Catacombs). During our recent visit at Lava Beds we explored Valentine Cave, one of the most accessible in the park. The majority of the tubes are in the Mammoth Crater flow which is around 30,000 years old. Valentine is in a younger flow, around 12,000 years old, so it has less collapse debris than many of the older caves (although it is true that many fallen boulders were removed by CCC workers during the Great Depression). In any case, the passages are easy to negotiate.

Being composed of very dark rock that tends to absorb light, tubes are notoriously hard to photograph. Flash photography tends to produce washed-out photos with little depth. I was using a bright flashlight for illumination and was holding it at arms length to get shadows that provide a sense of depth. I tried using my normal 'sophisticated' camera, but I actually got better results from my Samsung phone!

There are many interesting flow structures in the caves, including the pahoehoe flows on the floor of the caves, and "bathtub rings" on the walls showing that some flows only filled the cave a third full.

The basalt fractured as it cooled, forming the numerous cracks in the roof of the cave. Subsequent weathering in the soils above produced sodium bicarbonate and other chemicals that stain the edges of the fractures.

A lava cascade emerges from a side passage in Valentine Cave.

The lava tubes of Lava Beds National Monument are a fascinating environment to explore. Some of the caves have multiple levels, and some are decorated with permanent ice. One, Fern Cave, has numerous Native American pictographs and also ferns, which is interesting because ferns are not otherwise found in the park; they are a species of the western Cascades. The cool damp environment of the cave provided the right conditions for the plants, which may have arrived on birds feet (I'm guessing here).

There is a lot to do in Lava Beds. The ice cave and Fern Cave can only be visited with a ranger guide, but around twenty caves are open and developed for unaccompanied exploration. One, Mushpot Cave, is lit and has interpretive signs, and even a small amphitheater for ranger talks. On the surface there are lots of hiking trails that allow for the exploration of cinder cones, spatter cones, fault scarps, and the human history of the region (which will be covered in a separate post).

All in all, it's a good place to get under the skin of a volcano!

A Look Back at Ten Years of Geotripping: Dealing with the Dangerous Rays of Death

One of the greatest thrills of digital cameras is how easily they allow the documentation of celestial events. A 60x zoom is telescope grade, and yet is available on cameras costing less than $400. My history with digital cameras began 18 years ago, and their versatility has allowed me to document a large number of astronomical and meteorological phenomena. 2017 was a culmination as I was able to be in place to witness the total eclipse of the sun in August. But leading up to that day, I had put together a post of the what were to me the most fascinating sky events of my life so far. That post appeared on August 3 of last year...

Dealing with the Dangerous Rays of Death: Singular Solar Events I've Seen

Do you ever look at the sun?

Some advice: DON'T LOOK AT THE SUN! You can destroy your eyes!

Good, now that we have that out of the way, what is this post all about? The sun has been on my mind the last few days. I'm preparing for the final adventure of the summer, and it has a lot to do with the sun, most specifically, the only eclipse to cross the lower 48 states since 1979, the first to cross the country in 99 years, and the last to cross the American West until 2045. I got to thinking about the singular events that I've seen over the years that involve the sun in some way or another.

The sun. A diameter of about 860,000 miles, more than 100 times the diameter of the Earth. About 93,000,000 miles away from Earth. Big enough to hold 330,000 Earths. Containing 99.86% of the mass of the Solar System. The source of energy that makes life possible on Earth.

The most obvious moments that we might pay attention to the sun are during sunrise and sunset. Every one is different and unique. At those times, the sun is at eye level, and the thickness (and dirtiness) of the atmosphere provide a bit of protection for viewing with the unprotected eye. As the sun passes across the horizon, light is split into bright colors of the spectrum, providing a beautiful spectacle. I've probably taken thousands of sunset and sunrise pictures over the years, but here are two of my favorites, a sunset in Newport California a few years ago (above), and sunrise over Lake Rotorua in New Zealand in 2004 (below). To this day I cannot keep straight my internal compass; I couldn't help but think the sun was rising in the west (it wasn't). Lake Rotorua is one of the world's rare geothermal regions with geysers. Hot springs in the lake account for the steam rising off the water.

A difficult phenomena to see related to sunsets is the green flash. It is a sudden flash of greenish light above the sun at the moment of sunset, and it is said to last only a second or so. As the sun dips into the horizon, the layers of the atmosphere will cause some of the sunlight to be refracted, with red and orange on the lower parts of the disk along with green (and rarely blue) across the top.

It takes some very specific circumstances to see the flash, a clear view to a distant horizon, most often along coastlines. I have relatives on the coast of Oregon, so I've had a fair number of chances to try and capture the moment. I may even have succeeded once or twice.

Rainbows are one of the most familiar optical effects associated with the sun. Most everyone has seen them, so it takes some unique circumstances to really set one apart from others. My favorite moment came with a monsoonal storm on the North Rim of the Grand Canyon last year. I was looking down at a rainbow in the depths of the canyon.

Rainbows involve the splitting of white light from the sun into its component colors of the spectrum. Caves and deep slot canyons provide another sort of splitting, that of the sun's energy into a more or less pinhole of light. I was exploring a lava tube in the Mojave National Preserve a few years back. It was dark inside, but there were a few small skylights, and the early afternoon sun came bursting through like a blast from alien phaser.

One of the more famous places to see beams of light from the sun is in Antelope Canyon, Arizona. A deep slot canyon, Antelope is one of the most popular tourist stops on the Navajo Nation. The sandstone canyon is more than 100 feet deep, and only a few feet wide at the top. One can actually jump across if it were allowed. Tours are offered all day, but one pays a premium around noon for the obvious reason that it's when the sun sends beams of light into the depths of the canyon.

The effect is truly spectacular, although one should be aware that as lonely as these pictures seem, I was shoulder to shoulder with other photographers snapping like crazy.

Another fascinating phenomena occurs when the Moon passes into the Earth's shadow, a lunar eclipse. They are not rare, happening around two times a year, and they can be seen simultaneously across the globe (as long as the moon is visible in the sky). 

Lunar eclipses are fascinating to watch, and it is surprising to realize just how much of the sun's light is reflected from the moon. At totality, the moon practically disappears except for some refracted light around the edge of the Earth. Hundreds of stars become visible that weren't there moments earlier.

In a ridiculous age when science has to convince some people that the Earth is not actually flat, a lunar eclipse can help. The Earth casts a circular shadow across the surface of the Moon.

And then there is the opposite number, those events that result from the Moon passing in front of the Sun, a Solar eclipse. Although the Sun is many times larger than the Moon, the Moon is much closer to the earth, and is thus big enough to blot out the sun entirely. Solar eclipses are rarer than Lunar eclipses, and total solar eclipses are rarer still. I've been able to photograph a number of partial Solar eclipses over the years. For me, it is a clumsy affair, trying to hold a filter over the lens while keeping the Sun in the frame, but I've surrendered to the use of a tripod a few times to make it work.

The picture above is one of my favorites because of the huge sunspots that were present during the Moon's transit across the disc of the Sun. If the eclipse occurs when the Moon is farther from the Earth (it has an elliptical orbit), an annular eclipse can occur, in which the Moon doesn't cover the entire disc of the sun. I caught the picture below in 2012.

And then there are the transits of the planets. These happen when a planet crosses the disk of the Sun. Only two planets can do this, Mercury and Venus, because they are the only planets with orbits that are closer to the Sun than Earth. I've witnessed two of them.

A transit of the planet Mercury took place in May of 2016. I almost missed it because of cloud cover, but they cleared enough for a couple of shots. There was a sunspot as well. In the picture below, the top arrow points to a sunspot. The lower arrow points to Mercury. It is a small planet, only barely bigger than the Moon, and it orbits much closer to the Sun. Such transits are only visible by binocular or telescope (with filters, of course).

Zooming in made Mercury a bit clearer (below). Transits of Mercury are not overly rare, occurring in 1999, 2003, 2006, and 2016. Another will take place in November of 2019, but then we will need to wait until 2032 to see another.

The rarest Sun-related event I've ever seen is a transit of the planet Venus. The one I witnessed happened in 2012 (below). Previous transits had been in 1874, 1882, and 2004. The next will not happen until 2117 (in December, if you are planning on watching).

The big event of all things Solar is of course a total Solar eclipse. As noted above, it's been decades since one took place in the lower 48 states, and next won't cross my neck of the woods until 2045. I'll be almost 90 years old if I make it that far. I've had the privilege of witnessing one, though, in 1991. It crossed the south end of Baja California at San Jose del Cabo. A small expedition from MJC drove the length of the Baja Peninsula to see the event, one of the great adventures of my life. I didn't get pictures at the time, as the best technology I had was a Kodak Instamatic. The pictures below are from Dr. William Luebke, MJC's retired astronomy professor.

There is nothing quite like the few moments of totality. The sky goes dark, stars and planets become visible, and the ambient temperature plummets (it was summer when we were there, and the temperature dropped from over 100 degrees to 80 or less; it was a relief). The corona of the sun becomes visible, and there may be solar prominences visible as well. We had more than four minutes of totality, more than usual.

It's going to be a zoo in Oregon in a few weeks, as literally millions of people are converging on the region to have a look at this rare event. We will be staying about an hour's drive from the path of totality, so I have no idea if we'll be able to even get to the dark zone through the gridlocked traffic. If we do, I'll be busy getting pictures to share, and if we don't...well...we'll always have Baja.

Dealing with the Dangerous Rays of Death: Singular Solar Events I've Seen

Do you ever look at the sun?

Some advice: DON'T LOOK AT THE SUN! You can destroy your eyes!

Good, now that we have that out of the way, what is this post all about? The sun has been on my mind the last few days. I'm preparing for the final adventure of the summer, and it has a lot to do with the sun, most specifically, the only eclipse to cross the lower 48 states since 1979, the first to cross the country in 99 years, and the last to cross the American West until 2045. I got to thinking about the singular events that I've seen over the years that involve the sun in some way or another.

The sun. A diameter of about 860,000 miles, more than 100 times the diameter of the Earth. About 93,000,000 miles away from Earth. Big enough to hold 330,000 Earths. Containing 99.86% of the mass of the Solar System. The source of energy that makes life possible on Earth.

The most obvious moments that we might pay attention to the sun are during sunrise and sunset. Every one is different and unique. At those times, the sun is at eye level, and the thickness (and dirtiness) of the atmosphere provide a bit of protection for viewing with the unprotected eye. As the sun passes across the horizon, light is split into bright colors of the spectrum, providing a beautiful spectacle. I've probably taken thousands of sunset and sunrise pictures over the years, but here are two of my favorites, a sunset in Newport California a few years ago (above), and sunrise over Lake Rotorua in New Zealand in 2004 (below). To this day I cannot keep straight my internal compass; I couldn't help but think the sun was rising in the west (it wasn't). Lake Rotorua is one of the world's rare geothermal regions with geysers. Hot springs in the lake account for the steam rising off the water.

A difficult phenomena to see related to sunsets is the green flash. It is a sudden flash of greenish light above the sun at the moment of sunset, and it is said to last only a second or so. As the sun dips into the horizon, the layers of the atmosphere will cause some of the sunlight to be refracted, with red and orange on the lower parts of the disk along with green (and rarely blue) across the top.

It takes some very specific circumstances to see the flash, a clear view to a distant horizon, most often along coastlines. I have relatives on the coast of Oregon, so I've had a fair number of chances to try and capture the moment. I may even have succeeded once or twice.

Rainbows are one of the most familiar optical effects associated with the sun. Most everyone has seen them, so it takes some unique circumstances to really set one apart from others. My favorite moment came with a monsoonal storm on the North Rim of the Grand Canyon last year. I was looking down at a rainbow in the depths of the canyon.

Rainbows involve the splitting of white light from the sun into its component colors of the spectrum. Caves and deep slot canyons provide another sort of splitting, that of the sun's energy into a more or less pinhole of light. I was exploring a lava tube in the Mojave National Preserve a few years back. It was dark inside, but there were a few small skylights, and the early afternoon sun came bursting through like a blast from alien phaser.

One of the more famous places to see beams of light from the sun is in Antelope Canyon, Arizona. A deep slot canyon, Antelope is one of the most popular tourist stops on the Navajo Nation. The sandstone canyon is more than 100 feet deep, and only a few feet wide at the top. One can actually jump across if it were allowed. Tours are offered all day, but one pays a premium around noon for the obvious reason that it's when the sun sends beams of light into the depths of the canyon.

The effect is truly spectacular, although one should be aware that as lonely as these pictures seem, I was shoulder to shoulder with other photographers snapping like crazy.

Another fascinating phenomena occurs when the Moon passes into the Earth's shadow, a lunar eclipse. They are not rare, happening around two times a year, and they can be seen simultaneously across the globe (as long as the moon is visible in the sky). 

Lunar eclipses are fascinating to watch, and it is surprising to realize just how much of the sun's light is reflected from the moon. At totality, the moon practically disappears except for some refracted light around the edge of the Earth. Hundreds of stars become visible that weren't there moments earlier.

In a ridiculous age when science has to convince some people that the Earth is not actually flat, a lunar eclipse can help. The Earth casts a circular shadow across the surface of the Moon.

And then there is the opposite number, those events that result from the Moon passing in front of the Sun, a Solar eclipse. Although the Sun is many times larger than the Moon, the Moon is much closer to the earth, and is thus big enough to blot out the sun entirely. Solar eclipses are rarer than Lunar eclipses, and total solar eclipses are rarer still. I've been able to photograph a number of partial Solar eclipses over the years. For me, it is a clumsy affair, trying to hold a filter over the lens while keeping the Sun in the frame, but I've surrendered to the use of a tripod a few times to make it work.

The picture above is one of my favorites because of the huge sunspots that were present during the Moon's transit across the disc of the Sun. If the eclipse occurs when the Moon is farther from the Earth (it has an elliptical orbit), an annular eclipse can occur, in which the Moon doesn't cover the entire disc of the sun. I caught the picture below in 2012.

And then there are the transits of the planets. These happen when a planet crosses the disk of the Sun. Only two planets can do this, Mercury and Venus, because they are the only planets with orbits that are closer to the Sun than Earth. I've witnessed two of them.

A transit of the planet Mercury took place in May of 2016. I almost missed it because of cloud cover, but they cleared enough for a couple of shots. There was a sunspot as well. In the picture below, the top arrow points to a sunspot. The lower arrow points to Mercury. It is a small planet, only barely bigger than the Moon, and it orbits much closer to the Sun. Such transits are only visible by binocular or telescope (with filters, of course).

Zooming in made Mercury a bit clearer (below). Transits of Mercury are not overly rare, occurring in 1999, 2003, 2006, and 2016. Another will take place in November of 2019, but then we will need to wait until 2032 to see another.

The rarest Sun-related event I've ever seen is a transit of the planet Venus. The one I witnessed happened in 2012 (below). Previous transits had been in 1874, 1882, and 2004. The next will not happen until 2117 (in December, if you are planning on watching).

The big event of all things Solar is of course a total Solar eclipse. As noted above, it's been decades since one took place in the lower 48 states, and next won't cross my neck of the woods until 2045. I'll be almost 90 years old if I make it that far. I've had the privilege of witnessing one, though, in 1991. It crossed the south end of Baja California at San Jose del Cabo. A small expedition from MJC drove the length of the Baja Peninsula to see the event, one of the great adventures of my life. I didn't get pictures at the time, as the best technology I had was a Kodak Instamatic. The pictures below are from Dr. William Luebke, MJC's retired astronomy professor.

There is nothing quite like the few moments of totality. The sky goes dark, stars and planets become visible, and the ambient temperature plummets (it was summer when we were there, and the temperature dropped from over 100 degrees to 80 or less; it was a relief). The corona of the sun becomes visible, and there may be solar prominences visible as well. We had more than four minutes of totality, more than usual.

It's going to be a zoo in Oregon in a few weeks, as literally millions of people are converging on the region to have a look at this rare event. We will be staying about an hour's drive from the path of totality, so I have no idea if we'll be able to even get to the dark zone through the gridlocked traffic. If we do, I'll be busy getting pictures to share, and if we don't...well...we'll always have Baja.

Dreams of Summer: Going Underground on New Mexico's Continental Divide

When one thinks of the Continental Divide, one might imagine high peaks of the Rocky Mountains, piercing the sky with glacially carved ridges. It's not always quite that way. As we made our way last summer across the flat plateau lands east of Petrified Forest National Park, we passed the Zuni Pueblo, and reached a forest of Ponderosa pines.

The flat highway crossed a barely perceptible rise, and we almost missed a sign that said we were crossing the Continental Divide. Somehow, we had driven to an elevation of more than 8,000 feet and barely noticed. We crossed the divide and entered El Malpais National Monument.

It was late in the day and we were on a tight schedule, so we didn't have time to explore this strange and wonderful landscape as much as we might have wished, but we couldn't pass up the chance to go underground for a while.

El Malpais (Spanish: "Bad Lands") lies at the edge of the Colorado Plateau where it drops off into the Rio Grande Rift. The rift valley a vast fault trough where the continent started to split apart starting 30 million years ago. Rifting is never a gentle process, and the tearing of the crust allows magmas to form and erupt. Most of El Malpais National Monument is a geologically recent series of basalt flows, the youngest ranging in age from 2,500 to 17,600 years ago.

Basaltic lavas are more fluid than silica-rich lavas like andesite or rhyolite. They can flow for miles before cooling, but the flow is aided by the formation of a crust on the surface. The crust acts as insulation, keeping the lava hot and fluid. At times, especially near the end of the eruption sequence, the lava drains from under the crust, leaving behind a system of linear caves called lava tubes. That's what we were visiting that evening. There are undoubtedly many lava tubes in the park, but four are specifically open for exploration.

Junction Cave is several hundred feet long and is easily accessed at the end of a short trail off the main highway. If you intend to visit, be sure to get a free permit from the visitor center. The cave is bat habitat, and the park is extremely worried (with good reason) that the white-nose fungus might attack the bats. The fungus has decimated bat populations back east, and has been moving west over the last few years.

Lava tubes are not "decorated" in the manner of limestone caverns, as solution (the origin of stalactites and the like) is not a prominent process in the volcanic rocks. On the other hand, there are occasionally flow structures and drip structures ("lavacicles") that can be seen. Some of the caves may even preserve ice masses long after winter has ended (there is a commercial ice cave at the park boundary).

New Mexico is famous for caves, Carlsbad Caverns being one of the premier caves of the world. But in some little forgotten corners there are interesting caves of a completely different kind.