A choropleth map of the United States visualizes total earthquakes per state on a geographic projection, using a color scale that encodes the logarithmic earthquake count. State regions are colored according to their assigned region, with a sequential color scheme from `schemeOrRd`. The map is rendered as SVG paths using `d3.geoPath` with a `geoAlbersUsa` projection, and earthquake data is loaded from a CSV file. Hovering highlights a state in light green with a dark red stroke.