Talca Province, Chile

The Chilean coast suffered a tsunami triggered by an earthquake in 2010, creating after-effects that continue to flow upstream. Each upstream effect suggests that a single “natural” event is not where the damage lies, rather it is found in the layers of long-term, systemic damage initiated by unnatural causes. The tsunami laid bare the past. Making sense of the resulting friction is a challenge for researchers because the Chilean coast, as a largely industrialized zone, is the
result of centuries-long and ongoing exploitation. The procedures that scar the present include plantation forestry and the forced removal of Indigenous cultures. How can events be studied in the present without obscuring the past? Perhaps by tracing a description of a recent
event that exposes the overlap in otherwise disparate histories, between displacement and settlement, and among rivers, plantations, soils, and stories. A kind of narrative repair that commits to understanding more than accusation. My ambition in this case study is to learn how to better approach a vulnerable, injured landscape through creative research that pays attention to multigenerational and multispecies stories that survive despite the odds. After all, it is not only humans that make history. Diversifying our stories helps shed light both on how we inherit the past and how we might share the future.

The Estuary from
Earthquake to Tsunami

There are so many rivers along south-central Chile that the coastline is not so much a terrestrial edge, but a series of estuaries. Chile is typically understood from the mountains to the sea, a transect that rises in the Andes, flows along multiple rivers, intersects with low valleys, as water slows and irrigates cultivation before it reaches saltwater, and eventually the Pacific. The varied elevation along each estuarine setting distinguishes the rate of freshwater flow and the amount of seawater from the ocean, as life mingles, gathers, and circulates across tectonic boundaries. Those who seek boundaries will only find silty deposits, layered somewhere between above and below tides. Each layer is animated by wave action and reconfigured during tsunami events.

On 27 February 2010, an earthquake activated a tsunami deep below the Pacific Ocean, violently transporting marine waters towards estuarine geology, displacing the silty layers of each terrestrial elevation regardless of human possession, ritual, or safety. The official classification recorded 8.8 in magnitude, while the intensity of the earthquake was measured as IX class. The earthquake force triggered a devastating tsunami towards the coast of Chile, while it also generated unusually strong waves as far away as Indonesia, over 17,000 kilometers across the Pacific Ocean.

“Growing up, we learn Chile’s geography through a cut from east to west so that you see Argentina, big mountains, small mountains, ocean. But it is interesting that nobody cut Chile from Patagonia to Peru to show us all these little valleys between rivers, near estuaries. This is what gives us identity. There are similarities between people living in the mountains, the central valleys, or the coast, but when you go from valley to valley, from north to south, every river is different and defines people’s personalities, lifestyles, sense of humor. I think we should talk about our culture from valley to valley.”

          — Pablo González, kayak trip leader

The Maule River estuary outfalls at Constitución, one of the hardest hit communities following the tsunami in 2010. Extreme pulses of inundation are common to estuarine environments where marine sand meets river silt. At present, many estuaries along the Chilean coast are infilled by coastal concretization that intervenes between marine and terrestrial realms. The wave action following an earthquake brought silty inundation, erosion, and deposition to the estuarine coast, a disturbance that is neither unprecedented nor particularly unique. The lineage of estuary formation across time is described by paleo-geological analysis which confirms that the southwest coast of Chile is a remarkably active area on t

A rupture twenty-five kilometers deep beneath the Nazca plate, produced the earthquake, triggering a tsunami that traveled along the fault at tectonic junctions. The magnitudinous waves spread beneath the coast until making landfall along the shores between Constitución and Concepción. Magnitude is relative power, and its measurement takes into account the energy released at the source. By comparison, intensity is the strength of the shaking produced by the magnitude.