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thaumatology: the science, or knowing, of wonders and miracles
In many respects, we have only two-dimensional snapshot views of geologic processes. Moreover, the interpretation of geologic data was probably influenced by the psychological need to view the earth as a stable environment. Manifestations of current tectonism were often perceived as the last gasps of a geologically active past. Thus, subjected to the principle of least astonishment, (emphasis added) geological science has always tended to adopt the most static interpretation allowed by the data” -Leonardo Seeber, Doherty Senior Research Scientist, Lamont-Doherty Earth Observatory
image © jen-zed
This past week FOP visited the tectonically active area of Central California. As we landed at SFO, the geologically inflected writings of John McPhee and Joan Didion echoed in our minds. Our animal instincts set us on edge about what might unfold during our brief stay. Spatial tension grew as we drove past tightly packed houses clinging to anomalously steep streets. The whole of San Francisco seems not only to be flirting with the powerful geologic forces that raised its foundations to such precarious heights in the first place, but also to be queued up and ready to slide towards the sea at a moment’s notice. Surely that would be easier than clutching to these rollercoaster-like hills?
From ground level, the world teeters sideways out the car window. The street pushes a sharp 60+ degree angle. It seems that a small nudge (or rumble) is all the city needs to send structures rapidly planing towards the Bay. Sheer gravity rules at this extreme angle of inhabitation.
Around every corner, up every hill and across every bridge in San Francisco, the possibility of unexpected tremors palpably co-exists with the longer, slower stamina of geologic change. All of this coalesces into a mounting sense of imminent upheaval that taunts the fine edges demarcating land from water, infrastructure from rubble.
When considering the geologically liquid landscapes of California, the land is less matter of “form” and more a dynamic: here, form is motion | motion is form. To be in California is to live in constant relation to the unpredictable, and very real, tectonic forces that dwell within the earth. Forces that could transform the familiar into an astonishment.
While in California FOP spent a day seeking out geologic traces of the State’s moving edges. It turns out that pinning down what exactly marks the “edge” of California presents a challenge. During the Pleistocene there were eleven major glacial events, and several minors ones. Ocean levels rose and fell up to 100 meters+ over the entire surface of the Earth. So, some of what is now covered with water was dry land several thousand years ago. In fact, during the Pleistocene, the area that makes up the San Francisco Bay was a dry rolling plain teeming with megafauna.
At our first stop, Wilder Ranch, just a few miles north of Santa Cruz, we looked for a geologic feature called the marine terrace. Marine terraces mark both ocean levels AND the geologic force of tectonics. These terraces materialize the distinctly moving edge of California. Each terrace, which was once ocean floor, now appears as a hill, or wave cut bench, set back from the sea. Large stretches of the California coastline are marked with marine terraces that have been lifted into view by the active faults that live below them.
where the faults fall (image:USGS)
Here is a technical description of how the terrace building process works:
“These terraces are characteristic of exposed, windward coast where waves pound against the shore, cutting a vertical cliff face over time. The surging ocean then planes smooth the sea floor at the base of the cliff, forming the flat step of the submerged terrace. The existence of several terrace levels at one coastal site is evidence of the long-term geologic processes affecting the California coast. Between one and two million years ago the oldest and highest terraces were uplifted by the same mountain-building process that created the Coast Ranges. In addition to the incremental rise of the coast, the subsequent advance and retreat of Ice Age glaciers caused sea level to alternately drop and rise, and sequences of terraces were cut by waves and currents in the intervening periods of sea level stability.”
a schemata of the making of a marine terrace (image: USGS)
There are seven wave cut benches in the Santa Cruz area. In fact, most of the city of Santa Cruz exists on one. This contemporary city lives upon an ancient ocean floor. You can read more or take a self-guided tour of the terraces from this thorough USGS PDF. Or you can become a fan of the “Slow Coast” on Facebook, which has periodic lectures on the area’s geology (including the terraces). Further south, a remarkable thirteen terraces can be viewed at Palos Verdes Hills in Los Angeles County and twenty terraces from San Clemente Island.
On our expedition to Wilder Ranch we walked along two terraces. The first exists at current sea level. The second, called the Highway One terrace, was carved by fluctuating Pleistocene sea levels. It has been uplifted 41 meters into the air. The tallest of the seven benches, the “Quarry” terrace, has risen 240 meters. The exact rate of uplift proves elusive, but a relatively safe estimate appears to be around .44 meters every thousand years.
Stacking of time: looking across the marine terrace in Wilder Ranch State Park toward “Highway One.” The distant hill is the third elevated terrace (a former edge of CA). It was formed earlier in the Pleistocene Epoch (image: FOP 2010)
A flat field exists between the beach and Highway One. This field is the “Highway One Terrace”. This terrace formed more than 100,000 years ago -from the USGS
An aerial view of moving edges, highlighting the Pleistocene shaped wave cut bench east of Highway One (image: © cocoi_m)
The current edge in motion: the Old Cove Landing Trail at Wilder Ranch opens to the Pacific
Marine terraces are geologic time exposed, material timelines suspended in the open air. They make visible the reality that this edge of our continent is a dramatically active space. Incremental millimeters of movement eventually result in hundreds of meters of displacement. The terraces put us in contact with former worlds, worlds that we can never know directly, but that shape the surfaces that we can touch and walk upon today. A sense of wonder infuses such an experience. As artists, FOP understood only the most basic elements of terrace building. This afforded us a particularly sensational experience of the local geology. Indeed, our experience seemed the reverse of Seeber’s: we were subjected to the principle of most astonishment.
We left Wilder Ranch thinking of Peter de Bolla’s book Art Matters, a meditation on the sense of wonder. When curiosity is paired with a willingness to accept that what we see around us is far more complex than we can grasp in one view or lifetime, “being here” becomes a wonder-filled place with an active edge:
“The state of wonder, then, may be both compelling and disabling at the same time…it comes, as it were, before knowledge…wonder requires us to acknowledge what we do not know or may never know, to acknowledge the limits of knowledge. It is, then, a different species of knowledge, a way of knowing that does not lead to certainties or truths about the world or the way things are. It is a state of mind, of being with the world and oneself that… can, on occasion, certainly appear to be like thaumatology: the science, or knowing, of wonders and miracles.”–Peter de Bolla
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