FORGETTING AND REMEMBERING THE NEW MADRID EARTHQUAKES

ABSTRACT It has recently been argued that the large mid-continental earthquakes near New Madrid, Missouri, were mostly forgotten soon after they occurred in 1811–1812, in large part because the records available (historical narratives) were qualitative and taken to be unreliable. This obscurity is supposed to have lasted until the 1970s or later, when scientific study of the earthquakes resumed, and their significance for hazard became recognized. An examination of a wider range of sources suggests that while the memory of these earthquakes may have suffered the natural fate of most historical events, and faded in the broader population, the professional community of seismologists and engineers never lost sight of these earthquakes. Increased research in the 1970s on seismic hazards in mid-continental North America happened because of new opportunities created by funding and new technology, not a sudden remembering. Nor were these earthquakes neglected because seismology turned from description using descriptive measures (intensity of shaking) to analysis using instrumental data: intensity data were collected and used throughout the twentieth century.