Protogaea Civica II (Franciscan Formation/San Francisco, CA)


The work, Protogaea Civica II (Franciscan Formation/San Francisco, CA), is the second and largest of three variations of the Geology Flags Project, a system of symbolic demarcation of site-specific geologic structures and materials using flags. This version uses 19 flag poles at the San Francisco Civic Center Plaza as part of the 2005 exhibition, High Five, presented in conjunction with the opening of the new DeYoung Art Museum in Golden Gate Park, sponsored by the International Center for the Arts at San Francisco State University, in association with the San Francisco Arts Commission, the San Francisco Botanical Garden at Strybing Arboretum, and the de Young Museum.

The flags used in Protogaea Civica II (Franciscan Formation/San Francisco, CA), emblematically identify the Civic Center’s site in relationship to the Franciscan Formation, the bedrock beneath the larger Bay Area, east of the San Andreas Fault. The Civic Center, in geologic terms, rests unconformably (a time gap in deposition) on part of the Franciscan called the Alcatraz Terrane, near its western edge. The Alcatraz Terrane is a large block of primarily 135 million year old meta-greywacke, a sub-greenschist-grade metamorphic marine sandstone1, accreted by the process of plate tectonics onto the coast of Central California forming part of what is know known as the Coast Ranges. This terrane is bordered and underthrust to the west of the plaza by the Hunters Point Shear (or Mélange) Zone, a shale matrix with suspended blocks of other Franciscan rocks. The Alcatraz Terrane’s sandstone and Hunters Point Mélange are represented by the flags on the 18 central poles of the Civic Center Plaza. The large pole at the corner of Polk and Grove Streets has a series of Index flags representing materials of the larger Franciscan Formation including architectural copper (the façade of the DeYoung Museum), contextualized within this group as a Holocene Era constituent.

The complete set of flags of the Geology Flags Project are envisioned as a comprehensive system of geo-taxonomy, an indexing and revealing of the geologic materials and structures beneath any given site, and, as flags flying above civic sites, such as the San Francisco Civic Center, staking a claim for the “nationhood” of nature and natural systems. The flags temporarily displaced at the Civic Center, by Protogaea Civica II (Franciscan Formation/San Francisco, CA), are political, national and regional history flags. The geology flags refer to geologic history and boundaries - cultural history is temporarily displaced and re-articulated by nature. The Alcatraz Terrane – Hunters Point Shear Zone boundary, indicated by the flags, re-contextualizes normally perceived political boundaries. The Franciscan Formation itself crosses the California-Oregon border, similar accreted terranes are known along the west coast of the entire western hemisphere, crossing many national and regional boundaries.

The full expression of the flag system would have a range from pure chemical elements through mineralogy, paleontology, processes, materials, formations, tectonic structures and architectural analogs present above, beneath and/or extending from a site of study. The diagrams on the flags are derived from geologic and architectural symbols for materials and processes and can be used in different combinations to describe any site with new flags for special or new attributes being generated as needed. The ideal installation would involve numerous flagpoles distributed throughout an extended site with appropriate flags on each pole indicating the lateral changes in geologic information below, like free-standing core samples. The architectural extension of the geologic materials displayed as flags at appropriate sites correlates the built environment and the contemporary Holocene era with subterranean materials and time-frames. This idea refers to the concept of anthroturbation,2 described in an essay written about the work, Holocene Terrace, shown at Lance Fung Gallery, NY, NY, 1999, an extract follows:

" Cities, architecture, roads and other civic constructions made by mankind of earth materials during our Epoch (the Holocene) may be considered in a geologic context as forms of anthroturbation. This term describes the disturbance, dislocation and restructuring of geologic formations and materials by human agencies into new forms. These processes have analogies in the natural world, such as: mining as erosion, transport as flow and construction as sedimentation. Likewise, the built topography of a city can be understood in geomorphic terms: streets as canyons, buildings as plateaus, sewers as caves and plazas as playas."

John Roloff, 2005

1. Wakabayashi, J., 1992, Nappes, Tectonics of Oblique Plate Convergence and Metamorphic Evolution related to 140 Million Years of Continuous Subduction, Franciscan Complex, California Journal of Geology, v. 100, p. 19-40., and in e-mail conversation.

2. This term was developed in conversation with the geophysicist, Paul Spudich.

 

Installation View North; Installation View West: Installation Detail: Anthroturbation Flags; Flag Details

Protogaea Civica I (Franciscan Formation/San Francisco, CA) - Topographies Exhibition, 2004;

Protogaea Civica III (Santa Rosa)
- Sonoma County Museum of Art, 2006

Selected/Recent Projects