That's My Fault

Artist Statement

In this work, I explore brittle deformation in the lithosphere through the plastic medium of ceramics. The idea to fault and deform clay came to me very early in the process of designing my contribution to this exhibit, as faulting in outcrop can produce striking features that I thought would translate well to ceramics. Throughout the design process, I felt like my vision naturally became whole as I experimented and considered all the details that went into this project.

The initial form of my piece was wheel thrown, requiring a plastic clay body that mimics the behavior of deep crustal rocks that deform instead of fracturing. Whereas rocks become ductile at high temperatures and pressures, clay becomes ductile as water is added as a lubricant, allowing individual platy-structured clay minerals to slide against each other. If I had tried to “fault” my mug directly after throwing it while the clay still deformed plastically, my piece would have folded instead of fracturing. However, allowing the piece to dry reduced its plasticity enough for it to hold its shape during faulting, making the drying process an analogue to the decrease in temperature/pressure conditions experienced by rocks as they cross the brittle–ductile transition zone in the crust.

After drying, the process of creating my fault consisted of cutting the vessel in half with a metal rib tool, scoring the break, wetting, and joining the two halves of my piece. This created a weak plane in the clay, much as a fault surface is a weak plane in a body of rock. Fault surfaces in rock don’t stay weak forever, though, and can heal, regaining strength through a variety of processes. One of these processes, as discussed in Hirono et al. (2020), is sintering, where clay minerals under high temperatures or pressures become one interconnected mass. The conditions required for sintering occur in fault gouge due to seismic slip, but the conditions of a kiln also allow sintering to occur. After my piece was bisque fired, the slip created as I offset my vessel (my analogue to fault gouge) sintered, returning a lot of strength to the “fault” surface.

Much of my initial experimentation for this project consisted of using stains and glazes to highlight the offset of my piece. With more time to iterate, I would have loved to lean more into oxide staining, but it proved to be too unpredictable in the time that I had. I incorporated some iron oxide stain along the “fault,” but I glazed the piece as a whole to have slightly different colors on the hanging wall and footwall to portray how faults can juxtapose different lithologies against each other.

References

Hirono, T., Kaneki, S., Ishikawa, T. et al. Generation of sintered fault rock and its implications for earthquake energetics and fault healing. Commun Earth Environ 1, 3 (2020). https://doi.org/10.1038/s43247-020-0004-z (opens in a new tab)