Daily it is forced home on the mind of the geologist that nothing, not even the wind that blows, is so unstable as the level of the crust of this Earth.
-Charles Darwin
Our journey to Washington's third largest state park traversed the traffic-congested freeways through Washington's urban core, over the snow-covered lowest passage across the Cascade Mountains at Snoqualmie Pass and through the steadily drier farms and rangelands of the eastern slopes. Eventually, we drove into the mostly treeless steppes of one of the most startling geological features on the face of the planet--the Columbia River Basalt Group. 80,000 square miles of Washington and Oregon are covered by this layered outpouring of Earth's guts. Mostly between 17 and 14.6 million years ago, vast eruptions of lava from vents 15-30 feet wide and up to 10 miles long surged across this landscape. Flowing at speeds approaching 20 miles per hour some flows traveled over 450 miles, moving from deep in eastern Washington all the way to the Pacific Ocean.
The lichen-burnished cliffs of Ginkgo Petrified Forest State Park provide a window into a section of those outpourings with a cunning twist. Preserved in these 7,124 acres are the remains of ancient muddy marshes and lakebeds that developed on the "level of the crust" in between lava outbursts, and by a fortunate (for our current enjoyment) set of circumstances, exquisitely preserved the forms of thousands of forest giants growing in the marshes or carried there by floods and volcanic lahars (superheated mudflows). They were buried there as stumps or fallen logs and hermetically sealed in time by the onslaught of tongues of glowing lava. Hot lava coming in contact with the wetlands and pools quenched on contact, forming pillows that coalesced around the waterlogged trees, ensuring that they would escape incineration. Buried wood usually decays, but in this unusual setting, groundwater rich with silica and other minerals from the cooling basalt lava penetrated the wood replacing its cellulose bit by bit, cell by cell, eventually becoming stone suffused with brilliant mineral color patterns.
Why is there such a spectacular collection of petrified wood right here, you ask? As flows advanced over the land, the ancestral Columbia River was repeatedly pushed westward to the margins of the flows (the east slopes of the rising Cascade Mountains), and major disruptions of hydrology occurred, leading to the formation of lakes and swamps in the marginal areas, a perfect set-up for petrifaction as they were overwhelmed by subsequent outpourings.
These surges of lava must surely qualify as one of the great "catastrophes" in Earth's history.
In the late 18th and early 19th centuries , the scientific discipline of geology was finding its footing in the observations and writings of British naturalists James Hutton and Charles Lyell. Along with colleagues in other branches of science, they sought to shake the absolute power of religious autocrats, dispelling the notion of an omniscient deity responsible for every aspect of existence with the doctrine of uniformitarianism -- the natural laws and processes that operate in our present-day scientific observations have always operated in the universe in the past and apply everywhere in the universe --the present is the key to the past, operating on the Earth's surface in a gradual, predictable, measurable way over great spans of time. This set them in opposition to catastrophism, the belief that earth processes were sudden and dramatic, probably under the direct control of God.
In his book The New Catastrophism, geologist Derek Ager noted that modern "geologists do not deny uniformitarianism in its true sense, that is to say, of interpreting the past by means of the processes that are seen going on at the present day, so long as we remember that the periodic catastrophe is one of those processes."
Our first stop in the park was a stroll along the Trees of Stone Interpretive Trail. Informative, with species identifications of the exposed petrified pieces, but also a bit underwhelming as all displays are fenced, bricked exhibits. What comes through, though, is the exquisite detail of form preserved by the petrifaction process--it seems you could collect a few shards together and get a campfire going pretty easily!
Next up was a more adventurous sortie into the backcountry of the park, requiring a self-register permit and call in to a recorded message with the daily padlock code to open a gate and proceed onto a rugged bit of primitive road. Creeping through tumbled rocks at a rate often not much more than a spirited walking pace, we had covered about 2 miles when Patty shouted "STOP!" Thinking there was a road hazard I had missed, I braked to a halt. Luckily, the occasion was much more delightful--a group of 10 bighorn sheep ewes lounging away a Sunday morning on the slope above. We watched for awhile, blessed by the opportunity to observe these rare denizens of the shrub-steppe.
This group, part of the Quilomene herd, one of 18 distinct populations reintroduced to Washington, was gender-segregated, as bighorns usually are. Bighorns were extirpated in Washington in the 1920's, mostly due to infection by Mycoplasma ovipneumoniae transferred from flocks of domestic sheep. Infection from domestic sheep remains the greatest threat to Bighorn survival still, but a unique pilot program here may be turning that around. The Washington Department of Fish and Wildlife has partnered with inmates at the Washington State Penitentiary to provide a reserve of pathogen-free sheep. Willing sheep owners can replace pathogen carrying members of their flock with the reserve sheep in the penitentiary herd. Of course, at the heart of any recipe for the Bighorns' success is ensuring that there is a place that they can live with sufficient "social distancing" from infected sheep to live healthy lives.
That it has taken 100 years to arrive at this accommodation to ensure the survival of this species is not surprising when we see the initial response of so many Americans to the threat of COVID-19. Choosing to ignore science-based recommendations, demonizing foreigners and fellow citizens on the basis of race, failing to ramp up basic preparedness, and subscribing to conspiracy theories sadly set the stage for circumstances that weaken all of us.
We continued along the steadily-deteriorating road a couple more miles to a point near a rumored feature that has intrigued me since I saw it in an old photo from a half-century ago. With a bit of photo triangulation and some help from Google Earth, I felt that I had pinpointed the coordinates. So we parked the car, hoisted our packs and trekking poles and headed off through the pungent sagebrush to the point I had marked on the topo map. A bit of navigating later and we came up over a rise and looked down upon......
A 10 foot tall standing petrified tree stump!!
What a delight to be in the presence of this monument from another era, this witness to catastrophe on a scale that is beyond imagining, even for a veteran arm-waving geologist like myself.
We stayed for awhile, looking at the detailed textures from every side and angle, the feel of wood translated into quartz, buried for millions of years, revealed now, weathering into this place, colonized by colorful lichens.
The geologic view of the Earth is so intriguing to me because of the revelations that become apparent the longer one studies a particular place. From our perspective in the Anthropocene, it may be difficult to determine the outlines of the periodic catastrophe that we are inhabiting, as it doesn't seem as dramatic to us as the lava flows of the Columbia River Basalt Group. Nonetheless, the impact on the geologic record may be commensurate.
We know what is happening. We know what must be done. We only lack the fortitude and leadership to do it.
-David