Earthquake Sample

This page provides a complete sample response for an earthquake hazard from the Active Hazards API endpoint. This example demonstrates the full structure of an earthquake hazard object, including incident details, ShakeMap coverage data, alert geometry, exposure areas, and exposure assessment data.

Earthquake-Specific Properties

Incident Data

The incident.properties object of the earthquake provides detailed seismological data sourced from the USGS National Earthquake Information Center (NEIC). This snapshot includes several key properties that describe the physical characteristics and impact potential of the earthquake.

Key incident properties for earthquakes include:

• magRounded - Rounded magnitude of the earthquake (e.g., 5.5)

• mag - Precise magnitude value from USGS

• depthKm / depthMile - Depth of the earthquake in kilometers and miles

• place - Human-readable location description

• title - Full hazard title including magnitude and location

• magType - Magnitude type used for measurement (e.g., mww, Mi, mb)

• tsunami - Tsunami flag (0 = no tsunami warning, 1 = tsunami warning issued)

• sig - Significance score (0-1000) combining magnitude, felt reports, and damage

• mmi - Modified Mercalli Intensity estimate (decimal value representing expected shaking intensity)

• alert - PAGER alert level indicating estimated impact (green, yellow, orange, red)

• cdi - Community Decimal Intensity from "Did You Feel It?" reports

• felt - Number of "Did You Feel It?" responses received

• url - Direct link to the USGS earthquake event page

• detail - URL to the USGS GeoJSON detail feed for this event

• id - USGS event identifier (e.g., us7000s2bn)

• code - Event code portion of the identifier

• ids - Comma-delimited list of associated event IDs from contributing networks

• net - Preferred contributing network (e.g., us, ak, ci)

• sources - Comma-delimited list of contributing network codes

• types - Comma-delimited list of available product types (e.g., shakemap, losspager, moment-tensor)

• nst - Number of seismic stations used to determine location

• gap - Largest azimuthal gap between adjacent stations (degrees)

• dmin - Minimum distance to the nearest station (degrees)

• rms - Root-mean-square travel time residual (seconds)

• time - Origin time of the earthquake in epoch milliseconds

• updated - Time when the event was last updated in epoch milliseconds

• status - Review status of the earthquake data (e.g., reviewed, automatic)

• shakemapVersion - Version of the ShakeMap product available for this event

• latitudeRounded / longitudeRounded - Rounded epicenter coordinates

• featureType - Feature classification (INCIDENT)

• reportDate / eventDate - ISO 8601 timestamps for the report and event

• coordinate - Epicenter location as a spatial reference object

• ingestedAt / processedAt - Internal timestamps for data pipeline processing (epoch milliseconds)

• coveragePgaHighRes - High-resolution Peak Ground Acceleration grid data from ShakeMap (see below)

ShakeMap Coverage (coveragePgaHighRes)

When ShakeMap data is available from the USGS, the coveragePgaHighRes property contains a high-resolution gridded Peak Ground Acceleration (PGA) dataset following the OGC CoverageJSON specification. This data represents the estimated ground shaking intensity across the affected area.

Structure:

• domain - Defines the geographic grid with x (longitude) and y (latitude) axes, including start/stop bounds and number of grid points (num)

• parameters.PGA - Describes the parameter as Peak Ground Acceleration with units in natural logarithm of "g" (gravitational acceleration)

• ranges.PGA - Contains the actual grid values as an NdArray with shape [y, x]. Values are ln(g) — convert to %g using exp(value) * 100

Features

The features property is null for standard earthquake hazards. When ShakeMap data is available from the USGS for significant earthquakes, this property may be populated with shake intensity contours and related geospatial features.

Exposure Areas

The exposureAreas property contains a GeoJSON FeatureCollection with polygon rings around the earthquake epicenter representing expected ground shaking intensity. The number of levels varies based on earthquake characteristics and available ShakeMap data:

• Level 1: Moderate (V) to Strong (VI) shaking

• Level 2: Very Strong (VII) shaking (when applicable)

• Level 3: Severe (VIII+) shaking (when applicable)

Exposure Assessment Units

The exposureAssessment object uses the following units:

• foodNeedsUnit: MRE (Meals Ready to Eat)

• waterNeedsUnit: gal (US gallons)

• wasteNeedsUnit: 25 gal (25-gallon units)

• shelterNeedsUnit: sq feet (square feet)

Sample Response

{
  "name": [
    {
      "locale": "en",
      "value": "Earthquake - 5.5 - 95 km S of Nikolski, Alaska"
    }
  ],
  "description": [
    {
      "locale": "en",
      "value": "An earthquake with a magnitude of 5.5 at a depth of 17.0 km (10.56 miles) has occurred at 95 km S of Nikolski, Alaska, as reported by the National Earthquake Information Center (NEIC) of the USGS on March 05, 2026 19:25:07 UTC.\n\nBased on the preliminary data, earthquakes of this depth and magnitude are expected to result in moderate to severe shaking in the affected area. Models do not show a significant concentration of population within the affected area. Additional information will be provided as it becomes available by official sources.\n\nEpicenter: Latitude: 52.0753, Longitude: -168.9639\n\n"
    }
  ],
  "severity": "WATCH",
  "category": "EVENT",
  "incident": {
    "uuid": "ab6475ae-2811-49d0-bf6d-13e702340a18",
    "type": "EARTHQUAKE",
    "sourceId": 3,
    "sourceRecordId": "us7000s2bn",
    "properties": {
      "dmin": 0.851,
      "code": "7000s2bn",
      "magRounded": 5.5,
      "sources": ",ak,us,at,",
      "latitudeRounded": 52.0753,
      "mmi": 3.546,
      "title": "Earthquake - 5.5 - 95 km S of Nikolski, Alaska",
      "type": "earthquake",
      "magType": "mww",
      "shakemapVersion": "3",
      "nst": 112,
      "sig": 466,
      "tsunami": 1,
      "mag": 5.5,
      "reportDate": "2026-03-05T19:25:07.220000+00:00",
      "alert": "green",
      "gap": 111,
      "featureType": "INCIDENT",
      "rms": 1.05,
      "id": "us7000s2bn",
      "place": "95 km S of Nikolski, Alaska",
      "net": "us",
      "longitudeRounded": -168.9639,
      "types": ",dyfi,impact-link,losspager,moment-tensor,oaf,origin,phase-data,shakemap,",
      "coordinate": "{\"x\":-168.9639,\"y\":52.0753,\"z\":17.0,\"spatialReference\":{\"wkid\":4326}}",
      "depthMile": 10.56,
      "felt": 1,
      "cdi": 2,
      "depthKm": 17,
      "url": "https://earthquake.usgs.gov/earthquakes/eventpage/us7000s2bn",
      "ids": ",aka2026endjrb,us7000s2bn,at00tbfxxx,",
      "detail": "https://earthquake.usgs.gov/earthquakes/feed/v1.0/detail/us7000s2bn.geojson",
      "time": 1772738707220,
      "updated": 1772741305040,
      "status": "reviewed",
      "eventDate": "2026-03-05T19:25:07.220000+00:00",
      "coveragePgaHighRes": {
        "type": "Coverage",
        "domain": {
          "type": "Domain",
          "domainType": "Grid",
          "axes": {
            "x": {
              "start": -172.81667,
              "stop": -164.76667,
              "num": 484
            },
            "y": {
              "start": 49.61667,
              "stop": 54.58333,
              "num": 299
            }
          },
          "referencing": [
            {
              "coordinates": ["x", "y"],
              "system": {
                "type": "GeographicCRS",
                "id": "http://www.opengis.net/def/crs/OGC/1.3/CRS84"
              }
            }
          ]
        },
        "parameters": {
          "PGA": {
            "type": "Parameter",
            "description": {
              "en": ["Peak Ground Acceleration"]
            },
            "observedProperty": {
              "id": ["https://earthquake.usgs.gov/learn/topics/mercalli.php"],
              "label": {
                "en": "PGA"
              }
            },
            "unit": {
              "label": {
                "en": "natural logarithm of \"g\""
              },
              "symbol": {
                "value": "ln(g)",
                "type": "http://www.opengis.net/def/uom/UCUM/"
              }
            }
          }
        },
        "ranges": {
          "PGA": {
            "type": "NdArray",
            "dataType": "float",
            "axisNames": ["y", "x"],
            "shape": [299, 484],
            "values": [
              -8.59, -8.58, -8.58, -8.57, -8.56,
              "..."
            ]
          }
        }
      },
      "..."
    }
  },
  "uuid": "53b1c58a-d081-4e79-ba3a-c3331ac9e5b1",
  "comment": null,
  "createdAt": 1772741316,
  "relatedHazards": [],
  "longitude": -168.9639,
  "latitude": 52.0753,
  "version": 2,
  "alertGeometry": {
    "type": "FeatureCollection",
    "features": [
      {
        "type": "Feature",
        "geometry": {
          "type": "Polygon",
          "coordinates": [...]
        },
        "properties": null
      }
    ]
  },
  "features": null,
  "exposureAreas": {
    "features": [
      {
        "id": "1",
        "type": "Feature",
        "properties": {
          "exposureLevel": 1
        },
        "geometry": {
          "type": "Polygon",
          "coordinates": [...]
        },
        "sourceId": null
      }
    ],
    "type": "FeatureCollection"
  },
  "exposureAssessment": {
    "population": 0,
    "capital": 0,
    "exposureLevels": [
      {
        "level": "1",
        "data": {
          "population": 0,
          "capital": 0,
          "waterNeeds": 0,
          "wasteNeedsUnit": "25 gal",
          "wasteNeeds": 0,
          "shelterNeedsUnit": "sq feet",
          "shelterNeeds": 0,
          "foodNeedsUnit": "MRE",
          "foodNeeds": 0,
          "waterNeedsUnit": "gal"
        },
        "exposureDescription": "Moderate (V) to Strong (VI) Shaking"
      }
    ],
    "hazardUuid": "",
    "hazardType": "",
    "version": "",
    "timestamp": "1772742040904",
    "exposureDescription": "",
    "waterNeeds": 0,
    "wasteNeedsUnit": "25 gal",
    "wasteNeeds": 0,
    "shelterNeedsUnit": "sq feet",
    "shelterNeeds": 0,
    "foodNeedsUnit": "MRE",
    "foodNeeds": 0,
    "waterNeedsUnit": "gal"
  },
  "type": "EARTHQUAKE",
  "creator": "RICHTER",
  "source": null,
  "startedAt": 1772738707,
  "updatedAt": 1772742040,
  "endedAt": 1773084307
}

Note: In this sample, coordinate arrays in alertGeometry and exposureAreas have been replaced with [...] for brevity. In actual API responses, these properties contain complete GeoJSON coordinate arrays. The incident.properties object has been truncated with "..." to show only key fields — internal pipeline fields (__kafka_message_key__, sourceMessageHash, ingestedAt, processedAt, master_incident_id, craton, tz, name) are omitted from the sample. The coveragePgaHighRes.ranges.PGA.values array (144,716 float values in this example) has been truncated with "...".