Tag Archives: seismic risk

The Natures of San Francisco

Although ecosystems are the most living areas of cities, they remain hidden from view on city maps of the built landscape or paved roads that define the mobilty of “urban” life.  But we often fail to orient ourselves to the extent of urban environments in most maps. And the changing vulnerability of cites to climate change and extreme weather has directed increased attention to the vulnerability and instability of urban space, in ways we are still taking stock through maps, the question of what maps best orient us to the future of the city have provoked increased attention from maps of sea-level change, to maps of vulnerability to earthquakes and seismic risks. No city has been more subject to such demands for recalibrating its lived space, perhaps, than San Francisco, the city that is most conspicuously built on several fault lines–so much that the expansive recent downtown rebuilding is cast as a “seismic trap” or a disasters waiting to happen.

New York Times/

The dangerous vulnerability of cities has paralleled an attempt to try to take better stock of urban space than the map servers we use provide. For as any server only foregrounds a selective level of local detail, replicating a dominant focus on roads, paved spaces, and buildings, to the exclusion of the constricted habitat that remains on the edges of a city’s built space?  The historical attempt to design a wooden model encompassing a “Huge San Francisco” in detailt, back in the 1930s’ era of public mapping and public art, to preserve a record of the lived city in a set of interlocking 3D pieces that served as a snapshot of the lived city suggests just how much of the city was long green and open to “natural space” in a way that contrasts sharply with the image of the changing built environment of the city to give us pause–

Huge San Francisco/David Ramsey Historical Map Collection
Piece J 4 and Adjoining Pieces, David Rumsey Map Collection

–and to take stock of the natures of San Francisco, and the benefits of different forms of mapping its urban environment in less melancholy ways, and indeed of the importance of taking new stock of a city’s remaining open space–or what that open space is, and how we might best interact with greenspace remaining in the city, and the importance of how we map the urban spaces we live.

While San Francisco was long a center for nature preservation, and indeed the preservation of the country in the city, as the perceptive Bay Area geographer Richard Walker put it so eloquently, the organization of tools to uncover and preserve the current relation between ecological niches, natural environments and the built city becomes the project of the recent Nature in the City map, now in its third edition, offers the symbolic tools built on data to explore the urban environment–absent in most street maps or apps that we use to navigate the city, and to revalue the critical importance of native habitat in the open spaces existing within the city’s built environment, and offers an engaging and timely injunction to attend to and help cultivate it.

The suggestion of the city’s integration with not only its bay and shoreline, here shown as a thin strip of brown that borders on the Pacific, tied to historic estuaries, rivers, creeks, and current parks, presents an image of the city as an integrated whole, in which the blocks and streets foregrounded in GoogleMaps are far less prominent than the deeper continuities that create unique habitats, which are finally presented to the reader. We don’t see the Great Highway, for example, but the sand dollars and , and in Hunters Point find oysters and shorebirds–and in place of navigating a grid of grey, explore a region of butterflies, poppies, and jackrabbits, as well as a coyote, and even, out in the Pacific, the image–in the selection below just a glimpse–of a whale’s tail. The plentiful creatures within the vivid map, which breaks the barrier between cartography and art, reveals a far more engaging, and ethically challenging, question of what it is to map a city and to attend to the built space of a city as a place.

green edges, waters, habitat
Nature in the City map of San Francisco
Google Map of San Francisco from Great Highway

For rather than compile a survey of the built environment, and orient the river to streets, main highways and the neighborhoods we give to urban space, the static map offers an engaging relation to the habitability of a city so often bemoaned as increasingly unhabitable due to skyrocketing rents, gentrification, and evictions.

The quite distinct base-map that folks at Nature in the City organization adopted to invite us to view San Francisco helps to shift that set of associations, and to open up hidden spaces within the city to viewers in ways they might never have had access, putting the place of San Francisco as a part of the thin line of green coast and as a potentially rich set of open spaces, habitat and green.

The rent revisioning of the greenspaces that distinguish San Francisco displace the rush of commuting and explosion of jobs and rents for which the Bay Area may be increasingly known–

–and effectively invite viewers to navigate, and explore, a city where rents have withdrawn most of our attentions from the lived environment. The base map rich with data sets of the multiple green spaces in the city, from parks to all street trees and gardens, as if they and the surrounding waters afforded a palette–which if pictorial in nature, offers a synthesis of public data on open space.

And the data helps to situate the existing habitat that the non-profit has dedicated its energies to encourage, inviting viewers–and residents–to shift their attention from the city streets and built spaces to the conscious cultivation of the wild. The result is to re-focus attention on the habitats of specific animals, birds, fish, and plants across its urban space, in a static map that is made for an audience familiar with interactive mapping forms, and the coding of a rich natural space, extending to imagining its lost estuaries, underground rivers and watersheds, and even the historical shorelines of San Francisco before the addition of landfill.

Nature in the City 2018 (detail)

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Filed under data visualization, data visualizations, environmental geography, map design, San Francisco, San Francisco Bay

Mapping Fault-Lines in Earthquake Maps

Fracking–it is increasingly feared–invites irreparably contaminating our largest aquifers, and by extension drinking supplies–in Brooklyn, someone formed a group to protect the water of locally sourced beers–as well as devastate prairies and old agricultural lands, where land is cheap, by horizontal drilling.  Recent arguments compellingly link the drilling multiple “injection wells” of wastewater that seem to have activated previously non-active faults in regions that rarely experienced tremors in the past, and where the USGS did not find evidence of registered earthquakes.

As massive amounts of wastewater generated to access for natural gasses are forcefully re-injected into the earth, as if swept under a carpet, opening fissures in underlying beds of Shale or Sandstone.  Horizontal drilling operations have dated to 2008, mining areas by pumping vast amounts of sand into ancient shale formations in prairies and regions of declining agriculture to release methane and natural gasses.  Hydraulic fracking has used tons of water to force trapped gasses out of old rock formations.  Before 2009, in fact, earthquakes were rarely registered in the USGS surveys of lands where seismic activity has accompanied the injection of water into “injection wells”:  in these the shifting weight that the injected water that presses against rocks open old fissures, causing a buckling of underground rock formations, the fear is, as massive amounts of soupy, contaminated wastewater is injected back into the earth.  The “earthquake swarms” monitored nearby injection wells in Arkansas, Montana, Texas, Ohio or Oklahoma that barely registered seismic activity  from 1972 – 2008, has given new significance to–and created new fear around–a set of fault lines unknown to inhabitants, blamed as if active by an industry that rejects the accusations that they created sources for tremors inhabitants fear.   Indeed, the proliferation of earthquakes registered in the state of Oklahoma alone from 2001-15 reveals, according to the data from the Leonard Geophysical Observatory, a persistent increase in the tremor-like disturbances with the rise of underground wastewater dispersal, and a strikingly sharp increase in quakes of magnitude of three or higher in hears after 2010.

 

QUakes in OK, 2001-15.png

 

The increase seems closely tied to the absorption of wastewater back into rock layers whose weight is so altered by the injection of fluids, causing quakes that have rocked up to a fifth of the state, but have also increased land values for speculative fracking, in ways that may have concealed some interest in exploring the correlation–especially in a state where, due to geomorphological accident, water injected to reach deep-lying shale deposits send increasing amounts of wastewater underground, often to be absorbed by highly porous limestone that expands, but lies deep underground beside highly stressed layers of rock.  The result seems to create something like a combustive effect akin to the popping of kernels of corn, and has led many state officials to preemptively adopt prohibitions on local bans on regulating oil or gas wells in their jurisdictions, and insistence that the resurgence of quakes in fault zones is more able to be explained as an “act of nature that is nobody’s fault” not effected by human agency; the rejection of a relation to human activity comes from state legislatures fearful of the employment rises brought by gas and oil corporations from being scared away from the state.    But the geological record of apparently induced quakes in Oklahoma and their close proximity to existing injection wells.

 

ok.png

The fear of such tremors has a recent prehistory of three or so years.  An early tremor whose epicenter lay near Richmond, Virginia, of 5.8 magnitude, just below 6, but that sent shocks to North Carolina and Canada.  The event raised questions about the role of fracking in 2011 for Tim McDonnell and Aaron Ross, described in an earlier article in Mother Jones that directed attention to fracking’s consequences.  But the persuasive nature of recent USGS time-lapse maps of the same state–

The dangers of fracking echoes Jonathan Franzen’s early if compelling 1992 novel Strong Motion, in which mysteriously recurring earthquakes are pinpointed at the unlikely site of Boston, Massachusetts, a rare location of seismic activity.  But whereas Franzen’s protagonist, Renée Seitcheck, believed “that these earthquakes are the byproduct of industrial drilling” by a  petrochemical firm whose agents attempt to assassinate a beautiful rebel seismologist, for her mining of top-secret data from computers, the causes of the “swarms” seem to lie less in drilling than in injecting waste-water.  Was the novel remarkably prescient in unveiling a concealed impact of post-industrial geocaching?  It surely doesn’t seem so paranoid in its view of an industrial conspiracy to conceal geological findings, or to imagine the role of the rogue geographer in the seismically sensitive landscape that the search for underground sources of oil and gas can create.

But now it’s no longer isolated individuals who research the papers of top-secret labs.  There are upwards of 40,000 disposal wells actually active in the United States, some tunneling 13,000 feet under the earth, and “injection induced seismicity” is now a field, as the pressure exerted by the displacement of water able to move rock layers has provoked widespread academic interest and industrial concern:  “There are faults most everywhere,” noted Cliff Frohlich of the Institute for Geophysics at the University of Texas-Austin, suggesting how fracking can ‘reactivate’ fault lines which were never known; “Most of them are stuck, because rock on rock is pretty sticky.  But if you pump a fluid in there to reduce the friction, they can slip.”  “Water does not like to be squeezed,” Scott Ausbrooks of the Arkansas Geological Survey put it with some empathy.   And while Franzen’s character pored over reams of secret data to understand the relations of seismic activity to big oil’s search for underground pools of oil, such relations are now the focus of conferences and are amply documented in data maps.

The best known faults the USGS has mapped are well-known.  But, as Mark Zoback, a professor of geophysics at Stanford explained in a recent article by Michael Behar in Mother Jones, echoing Frohlich, “there are faults everywhere, and some are too small to be seen.”  Faults are widely known if often forgotten by those living in California, where fracking may begin, despite growing opposition.  Indeed the range of fault-lines throughout the California-Nevada region are so multiple that the possibility of hydraulic fracking in the region of southern California threatens to  imbalance a rather threatening constellation of seismic activity that already exists in much of the region, and is more widely mapped than the most familiar lines of the San Andreas, Calaveras, or Hayward faults.  The visibility of these fault-lines is available on an up-to-the-minute-map of regional seismic activity, part of a set of maps that record seismic activity by irregular bright red computer-generated lines, often proximate to cities:

California in USGS map of Faultlines

The nervously drawn red lines of seismic activity furrowing the green plains in these maps are ‘underground views’ mapping the range of pressure below the earth’s surface.  A more striking map of seismic activity of the past few weeks and days pieces together a narrative of fault-lines and tectonic plates that accentuate the daily deep divisions that course under the earth of our westernmost states:

California_Nevada-1

The stark legend suggests the huge growth in a magnitude the scale of “6.”  The prominent indexing of fault-lines in another USGS map of seismic activity, with less attention to topographic or climactic variation, shows the volatility of the region’s multiple faults in a similar if starker image of seismic frequency:

indexfault_map

 

More locally, and limited to faults active in the past week of a magnitude above 2.5,
California in USGS map of Faultlines

 

For more focus on recent seismic occurrence, link your browser to: http://earthquake.usgs.gov/earthquakes/map/

Despite the evidence of terrifyingly active fault lines, the active movement ‘Stop Fracking in California‘ has its back against the wall, even if they are growing in local Southern California chapters.

Yet the volatility of the region cannot be ignored–take this map of the Simi Valley and Los Angeles area, posted on Saturday, February 16, where fault-lines course unseen beneath the landscape, moving from inland to the coast at multiple points and through metropolitan Los Angeles:

Los Angeles earthquake faults

This interest to frack in California–an oddly post-modern verb–is scariest given maps approximating the future likelihood, as calculated by the USGS, that the regional fault-lines in the Bay Area will experience seismic activity at a magnitude greater than 6.7 before 2036.

2008probabilities-lrg

By how much would active injection wells multiply increase these already quite sizable odds?  Given the proximity of these lines to expanding urban areas, often growing between the Hayward and San Andreas fault, can fracking in California be a safe investment for the future?

This is not a map that is in the heads of most native Californians or residents.  The readability of these maps offers a base-line for future seismic activity, and grounds for concern about hydraulic fracking in seismically active regions.

It is good news that the USGS has expanded its clickable interactive image of global fault lines, in which the record of seismic activity is updated every minute, and on which viewers can scale in to investigate on their own:

USGS Global Earthquake Map

While the occurrence of faults and tremors will always shock, its legibility not only offers a lesson in continental drift.  Many of these jerky lines reminiscent of an etch-a-sketch lie underwater, but the points of greatest activity–in California, Indonesia, and Central America–cannot be ignored or lost sight of for underground engineers.

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Filed under data visualizations, Earthquake Probability, Earthquake swarms, earthquakes, Fracking