etc/nshm/map-la-basin.geojson

{
  "type": "FeatureCollection",
  "features": [
    {
      "type": "Feature",
      "geometry": {
        "type": "Polygon",
        "coordinates": [
          [
            [-119.8, 33.86],
            [-117.42, 32.94],
            [-116.7, 34.23],
            [-119.07, 35.15],
            [-119.8, 33.86]
          ]
        ]
      },
      "properties": {
        "spacing": 0.01,
        "title": "Los Angeles Basin – WGCEP 2007"
      }
    }
  ]
}