A Far Piece From Home - Travelogue 2017v8: Volcanoes & Caves at Lava Beds

This was a day of lateral movement, a west to east transect across northern California that brought us into and out of contrasting landscapes.  The morning began in the cool marine air and light fog under the towering forests at Patrick Point, where we shared space on the forest floor with fern and banana slugs.  We backtracked down Highway 101 through redwoods with their tops veiled in wisps of fog and then cut east over the Coast Range where it was noticeably more arid once we crossed the summit and cruised down the eastern slope.  Traffic picked up in Whiskeytown, a gold rush community turned vacation get-away development.  As we were coming into Redding at the northern end of the Sacramento Valley I pointed out that this was likely our best shot at lunch, and as we were about to engage in a rock-paper-scissors contest to decide burger-taco-chicken, we passed a Mediterranean Restaurant.  U-turn.  Rules say kabob trumps all.  Most of the traffic goes north-south through Redding on I-5, we were going east unlike the madding crowd - just the way a contrarian likes to do it.

Quickly pulling out of the Great Sacramento Valley, we were in the red-soil, volcanic province of the Cascade Range, home to stratovolcanoes Mount Shasta and Mount Lassen.  These are massive giants that live in the sky with power and strength to cast ash out to the middle of the continent and launch rocks nearly into space, cool the planet with a pall of dust and shake mortals into reverence with columns of fire and plumes of smoke.  For now they sleep, but Dr. Mack always told us in Geol 401; "Scholars, mark my words, one of these big guys is going to blow in your lifetime!"  [Dr. Mack's prophecy of 1976 was proven correct with Mt. St. Helens in 1980].  After an afternoon of driving across vast tracks of range land with seldom another vehicle among the cattle, pines and rugged volcanic rocks, we settled in at Lava Beds National Monument in the high desert of sage and lava.

Mount Shasta Cascade Volcano
From Captain jack's Stronghold
Lava Beds National Monument

For me, Lava Beds was a 'must see before I expire' kind of a place.  I scheduled a two day holdover here, with lava tube caves to explore, historical setting from the US-Modoc Indian war in 1873, a campfire under the most brilliant starry skies either of us had ever experienced and a great place for a little kick-around for any impromptu adventures that presented themselves, and for help with the latter, I brought along my own personal favorite igneous geologist (my wife).

Lava Beds National Monument is remote.  The Oregon border is in view from the knoll on which we camped and not many folks know of or make it out to this place.  I think I may have found my place in California that has not yet been ruined and all shot to hell with crowds.  Somehow, the Europeans have found the place though, we camped next to several Germans our first night, and after they vacated the camp, a rental RV with Danes pulled in.  I was told by the campground host that the French were nearby.  Amazing, go figure, eh?

There are 25 marked caves in the area formed as magma was extruded across the landscape a mere 30,000-40,000 years ago, as the magma cooled and formed a rock crust on the surface, the molten rock continued to flow beneath the crust, forming tubes that conducted the magma down hill, and leaving behind hollow tubes inside the lava flows.  Once the surface of the tube weathers and collapses, one can enter and explore these lava tube caves.  It is recommended that one carry multiple flashlights, a bump helmet and gloves and knee pads to explore the inner recesses.  I'd done my homework and had all of the above and we were ready for some spelunking. However, once the mama bats select a cave for their rookeries, the public is then kept out in deference to the baby bats.  That eliminated some of our choices for exploration targets.

We started the bright morning at the visitors center where we needed to get certified that were were not vectors of the 'White Nose Syndrome', a fungal infection that has been decimating the bat population in the US.  Once we submitted to questioning by the ranger that neither our boots, clothing or equipment had been in a cave or mine in the last 10 years, we got a "Uncontaminated Status" display card for the vehicle window.  We signed up for an afternoon ranger-guided tour of Sunlight Cave, but we were also intrigued by a rumor of Glass Mountain some 20 miles off of the National Monument property.

The Q parked at the toe of the
rhyolite flow from Glass Mountain

Bands of obsidian layered within
pumice and rhyolite

Indeed, we got pretty excited about locating Glass Mountain, a rhyolite extrusive event from only 900 years ago - a relative fraction of a second in goelogic time reckoning.  The ranger produced a photocopied hand-drawn map that showed forking dirt roads in an over-the-hill and through-the-forest kind of route, cautioning us that we may still encounter snow on the road (this is July).  I threw The Q into 4-Wheel Drive and we were off on our first impromptu adventure.  


The Forest Service Road took us to the toe of silica-rich flow that had been halted in its advance by a hillside.  We parked and rushed out of The Q to take a good look.  There were bands of obsidian layered with frothy pumice stone, and all manner of spectacular volcanic textures rarely seen, owning to the very recent activity here.  We were almost to the point of squealing with excitement, but managed to keep it to constantly calling to one another, "Hey come over here! Tell what you think this is?" 

I made the difficult scramble to the middle of a pile of crumpled blocks of obsidian and sat quietly for a moment in the breeze, and I could hear the slight glassy tinkle and the distinct sound of chipping of glass as this unstable pile shifted in the summer breeze ever so slightly.  But it was musical to hear these rocks sing to me as sat in admiration of this sight born of violent upheaval.

Recumbent fold of obsidian and pumice.
So many fascinating volcanic textures and features
displayed at Glass Mountain

We were back at camp for lunch and a chance to re-hydrate.  We checked our caving gear and headed out for our tour of Sunlight Cave.  We were introduced to 'dripstone' or 'lavacicles' formed by magma as it dripped off the cave ceiling and then cooled into a stone texture resembling icicles. We managed to explore five caves that afternoon, each with some unique features.  Golden Dome Cave was especially interesting with its high ceilings seemingly spattered with metallic gold paint, but the spectacular shiny gold ceiling surfaces are formed by actinomycetes bacteria, which is hydrophobic (i.e. causes water to bead up in its surface).  These were some of the many underground wonders that never see the light of day, but with a flashlight and helmet we were truly treated to inspiring beauty.

Dripstone or 'lavacicles'
Stone formed by molten lava dripping from the ceiling
pf a lava tube

Exploring Golden Dome Cave

Golden Dome Cave
actinomycetes bacteria make a the ceiling of this cave
sparkle gold among the dripstone

With the sun down, and our limbs mildly soar from the ducking, stooping and hiking around the lava beds and tubes, we sat mostly silent as the campfire died down to a few embers and as we tossed our heads back, the starfield above us was yet another spectacular dome of brilliant stars, the likes of which I have never experienced. 



 

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