# Enhanced Historical Earthquake Sample

This page provides a complete sample response for an enhanced historical earthquake hazard. Enhanced historical hazards use the **legacy DAE hazard schema**, which differs significantly from the V2 API response format used by the Active Hazards endpoint. This sample demonstrates the full structure of a legacy earthquake hazard object, including the `earthquakeAssessment` block with USGS ShakeMap data and PGA contours.

{% hint style="warning" %}
**Schema difference:** This response uses the legacy DAE hazard schema, not the V2 API format. Key structural differences include:

* Top-level fields use `snake_Case` naming (e.g., `hazard_ID`, `type_ID`, `create_Date`) instead of camelCase
* Earthquake-specific data is in `earthquakeAssessment` (not `incident.properties`)
* Exposure areas use `exposureArea` (not `exposureAreas`)
* Exposure assessment values are wrapped in `{value: ...}` objects
* Smart alert geometry is in `activeGeography` (not `alertGeometry`)
* Location metadata is in `locationDetails` (not present in V2)
* There is no `incident` wrapper object
  {% endhint %}

## Earthquake Assessment (Enhanced Data)

The `earthquakeAssessment` object contains USGS ShakeMap data for the earthquake, including Peak Ground Acceleration (PGA) contours as GeoJSON features. This is the primary enhancement over the base hazard record.

**Key properties:**

| Property            | Type    | Description                                         |
| ------------------- | ------- | --------------------------------------------------- |
| `usgs_event_id`     | string  | USGS event identifier (e.g., `us6000rt1x`)          |
| `shakemap_version`  | string  | Version of the ShakeMap product                     |
| `magnitude`         | number  | Earthquake magnitude from ShakeMap                  |
| `depth_km`          | number  | Depth of the earthquake in kilometers               |
| `source`            | string  | Data source (e.g., `USGS ShakeMap`)                 |
| `max_pga_pctg`      | number  | Maximum PGA value in percent-g                      |
| `max_pga_g`         | number  | Maximum PGA value in g (gravitational acceleration) |
| `max_mmi`           | string  | Maximum Modified Mercalli Intensity                 |
| `pga_contour_count` | integer | Number of PGA contour levels                        |
| `pga_contours`      | object  | GeoJSON FeatureCollection of PGA contour lines      |

### PGA Contours

The `pga_contours` property is a GeoJSON FeatureCollection containing MultiLineString features representing Peak Ground Acceleration contour lines. Each feature represents a specific PGA threshold level.

**Contour feature properties:**

| Property | Type    | Description                                       |
| -------- | ------- | ------------------------------------------------- |
| `value`  | number  | PGA threshold value in percent-g                  |
| `units`  | string  | Unit of measurement (always `pctg` for percent-g) |
| `color`  | string  | Hex color code for rendering the contour          |
| `weight` | integer | Line weight for rendering                         |

This sample includes 10 contour levels at the following PGA values (in %g):

| Value | Color     |
| ----- | --------- |
| 0.005 | `#ffffff` |
| 0.01  | `#ffffff` |
| 0.02  | `#ffffff` |
| 0.05  | `#fbfcff` |
| 0.1   | `#d3dcff` |
| 0.2   | `#b7d2ff` |
| 0.5   | `#a5e1ff` |
| 1.0   | `#96edff` |
| 2.0   | `#87f9ff` |
| 5.0   | `#7cffb7` |

## Exposure Assessment

The legacy schema wraps exposure values in `{value: ...}` objects and organizes exposure into numbered levels within an `exposureLevels` array. Each level includes population, capital, and humanitarian needs data.

**Exposure levels for this earthquake:**

| Level | Description                             | Population | Capital (USD) |
| ----- | --------------------------------------- | ---------- | ------------- |
| 1     | Moderate to strong shaking (30 - 100km) | 5.2        | $209,800      |
| 2     | Very strong shaking (10-30km)           | 0          | $0            |
| 3     | Severe shaking and above (0-10km)       | 0          | $0            |

## Legacy Hazard Field Reference

**Top-level hazard fields:**

| Field                    | Type    | Description                                              |
| ------------------------ | ------- | -------------------------------------------------------- |
| `hazard_ID`              | integer | Unique hazard identifier                                 |
| `uuid`                   | string  | UUID for the hazard                                      |
| `hazard_Name`            | string  | Full hazard title including magnitude and location       |
| `type_ID`                | string  | Hazard type (e.g., `EARTHQUAKE`)                         |
| `category_ID`            | string  | Category classification (e.g., `EVENT`)                  |
| `severity_ID`            | string  | Severity level (e.g., `ADVISORY`, `WATCH`, `WARNING`)    |
| `status`                 | string  | Active status (`A` = active)                             |
| `latitude` / `longitude` | number  | Epicenter coordinates                                    |
| `start_Date`             | string  | Event start time in epoch milliseconds                   |
| `end_Date`               | string  | Event end time in epoch milliseconds                     |
| `create_Date`            | string  | Record creation time in epoch milliseconds               |
| `last_Update`            | string  | Last update time in epoch milliseconds                   |
| `creator`                | string  | System or user that created the record                   |
| `update_User`            | string  | System or user that last updated the record              |
| `description`            | string  | Human-readable event description                         |
| `autoexpire`             | string  | Whether the hazard auto-expires (`Y`/`N`)                |
| `snc_url`                | string  | URL to the Hazard Brief page                             |
| `product_total`          | string  | Number of associated products                            |
| `tier`                   | string  | Access tier (e.g., `Enterprise`)                         |
| `tier_tag`               | string  | Short tier code (e.g., `ent`)                            |
| `master_Incident_ID`     | string  | Internal incident tracking ID                            |
| `org_ID`                 | integer | Organization ID (-1 for system-generated)                |
| `app_ID`                 | integer | Application ID                                           |
| `in_Dashboard`           | string  | Dashboard visibility flag                                |
| `locationDetails`        | object  | Structured location metadata (country, state, continent) |
| `activeGeography`        | object  | Smart alert area geometry with WKT polygon               |
| `exposureAssessment`     | object  | Structured exposure data with nested value objects       |
| `earthquakeAssessment`   | object  | USGS ShakeMap data and PGA contours                      |
| `exposureArea`           | object  | GeoJSON FeatureCollection of exposure area polygons      |

## Sample Response

```json
{
  "app_ID": 0,
  "app_IDs": "",
  "autoexpire": "Y",
  "category_ID": "EVENT",
  "charter_Uri": "",
  "comment_Text": null,
  "create_Date": "1765081686217",
  "creator": "DisasterAWARE (Automated)",
  "end_Date": "1765167587000",
  "glide_Uri": "",
  "hazard_ID": 357496,
  "hazard_Name": "Earthquake - 5.4 - 91 km N of Yakutat, Alaska",
  "last_Update": "1765081749586",
  "latitude": 60.3620376586914,
  "longitude": -139.51382446289062,
  "master_Incident_ID": "3.1765081709.2",
  "message_ID": "",
  "org_ID": -1,
  "severity_ID": "ADVISORY",
  "snc_url": "https://hazardbrief.pdc.org/PRODUCTION/ui/index.html?uuid=d6a7791c-778e-437d-af8f-596e510208e3",
  "start_Date": "1765081187000",
  "status": "A",
  "type_ID": "EARTHQUAKE",
  "update_Date": "1765081748635",
  "update_User": "apps.pdc.org",
  "product_total": "2",
  "uuid": "d6a7791c-778e-437d-af8f-596e510208e3",
  "in_Dashboard": "0",
  "areabrief_url": null,
  "description": "An earthquake with a magnitude of 5.4 at a depth of 0.39 km (0.24 miles) has occurred at 91 km N of Yakutat, Alaska, as reported by the National Earthquake Information Center (NEIC) of the USGS on December 07, 2025 04:19:47 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. Initial estimates indicate that 5 people, 2 households, and $209,000 (USD) of infrastructure* are concentrated within the affected area. Exposure estimates will be refined as additional data from official sources becomes available. Additional information will be provided as it becomes available by official sources.\n\nEpicenter: Latitude: 60.3620376586914, Longitude: -139.51382446289062\n*The cost represents the total replacement value of the infrastructure.\n\n",
  "roles": [],
  "updatedGeography": false,
  "tier": "Enterprise",
  "tier_tag": "ent",
  "activeGeography": {
    "magId": 1232501,
    "uuid": "fa69a993-d804-433d-aaee-98c6c0e681bc",
    "title": "AUTO GENERATED SMART ALERT",
    "createDate": 1765081748926,
    "magType": "Calculated",
    "creator": "apps.pdc.org",
    "isActive": true,
    "updateDate": 1765081748926,
    "wkt": {
      "text": "POLYGON((...truncated...))"
    }
  },
  "locationDetails": {
    "version": 2,
    "country": "Canada",
    "country_code": "CA",
    "country_code_3": "CAN",
    "continent": "North America",
    "subregion": "Northern America",
    "state_province": "Yukon",
    "state_code": "CA-YT",
    "location_type": "land"
  },
  "exposureAssessment": {
    "population": {
      "total": {
        "value": 5.2
      },
      "total0_14": {
        "value": 0
      },
      "total15_64": {
        "value": 0
      },
      "total65_Plus": {
        "value": 0
      },
      "households": {
        "value": 2
      },
      "vulnerable": {
        "value": 0
      }
    },
    "capital": {
      "total": {
        "value": 209800
      },
      "school": {
        "value": 0
      },
      "hospital": {
        "value": 0
      }
    },
    "exposureLevels": [
      {
        "level": "1",
        "exposureDescription": "Moderate to strong shaking (30 - 100km)",
        "data": {
          "population": {
            "total": {
              "value": 5.2
            },
            "total0_14": {
              "value": 0
            },
            "total15_64": {
              "value": 0
            },
            "total65_Plus": {
              "value": 0
            },
            "households": {
              "value": 2
            },
            "vulnerable": {
              "value": 0
            }
          },
          "capital": {
            "total": {
              "value": 209800
            },
            "school": {
              "value": 0
            },
            "hospital": {
              "value": 0
            }
          }
        }
      },
      {
        "level": "2",
        "exposureDescription": "Very strong shaking (10-30km)",
        "data": {
          "population": {
            "total": {
              "value": 0
            },
            "total0_14": {
              "value": 0
            },
            "total15_64": {
              "value": 0
            },
            "total65_Plus": {
              "value": 0
            },
            "households": {
              "value": 0
            },
            "vulnerable": {
              "value": 0
            }
          },
          "capital": {
            "total": {
              "value": 0
            },
            "school": {
              "value": 0
            },
            "hospital": {
              "value": 0
            }
          }
        }
      },
      {
        "level": "3",
        "exposureDescription": "Severe shaking and above (0-10km)",
        "data": {
          "population": {
            "total": {
              "value": 0
            },
            "total0_14": {
              "value": 0
            },
            "total15_64": {
              "value": 0
            },
            "total65_Plus": {
              "value": 0
            },
            "households": {
              "value": 0
            },
            "vulnerable": {
              "value": 0
            }
          },
          "capital": {
            "total": {
              "value": 0
            },
            "school": {
              "value": 0
            },
            "hospital": {
              "value": 0
            }
          }
        }
      }
    ]
  },
  "earthquakeAssessment": {
    "usgs_event_id": "us6000rt1x",
    "shakemap_version": "7",
    "magnitude": 4.1,
    "depth_km": 5,
    "source": "USGS ShakeMap",
    "max_pga_pctg": 5.0,
    "max_pga_g": 0.05,
    "max_mmi": "4.581",
    "pga_contour_count": 10,
    "pga_contours": {
      "type": "FeatureCollection",
      "name": "cont_pga",
      "crs": {
        "type": "name",
        "properties": {
          "name": "urn:ogc:def:crs:OGC:1.3:CRS84"
        }
      },
      "features": [
        {
          "type": "Feature",
          "properties": {
            "value": 0.005,
            "units": "pctg",
            "color": "#ffffff",
            "weight": 4
          },
          "geometry": {
            "type": "MultiLineString",
            "coordinates": [...]
          }
        },
        {
          "type": "Feature",
          "properties": {
            "value": 0.01,
            "units": "pctg",
            "color": "#ffffff",
            "weight": 4
          },
          "geometry": {
            "type": "MultiLineString",
            "coordinates": [...]
          }
        },
        {
          "type": "Feature",
          "properties": {
            "value": 0.02,
            "units": "pctg",
            "color": "#ffffff",
            "weight": 4
          },
          "geometry": {
            "type": "MultiLineString",
            "coordinates": [...]
          }
        },
        {
          "type": "Feature",
          "properties": {
            "value": 0.05,
            "units": "pctg",
            "color": "#fbfcff",
            "weight": 4
          },
          "geometry": {
            "type": "MultiLineString",
            "coordinates": [...]
          }
        },
        {
          "type": "Feature",
          "properties": {
            "value": 0.1,
            "units": "pctg",
            "color": "#d3dcff",
            "weight": 4
          },
          "geometry": {
            "type": "MultiLineString",
            "coordinates": [...]
          }
        },
        {
          "type": "Feature",
          "properties": {
            "value": 0.2,
            "units": "pctg",
            "color": "#b7d2ff",
            "weight": 4
          },
          "geometry": {
            "type": "MultiLineString",
            "coordinates": [...]
          }
        },
        {
          "type": "Feature",
          "properties": {
            "value": 0.5,
            "units": "pctg",
            "color": "#a5e1ff",
            "weight": 4
          },
          "geometry": {
            "type": "MultiLineString",
            "coordinates": [...]
          }
        },
        {
          "type": "Feature",
          "properties": {
            "value": 1.0,
            "units": "pctg",
            "color": "#96edff",
            "weight": 4
          },
          "geometry": {
            "type": "MultiLineString",
            "coordinates": [...]
          }
        },
        {
          "type": "Feature",
          "properties": {
            "value": 2.0,
            "units": "pctg",
            "color": "#87f9ff",
            "weight": 4
          },
          "geometry": {
            "type": "MultiLineString",
            "coordinates": [...]
          }
        },
        {
          "type": "Feature",
          "properties": {
            "value": 5.0,
            "units": "pctg",
            "color": "#7cffb7",
            "weight": 4
          },
          "geometry": {
            "type": "MultiLineString",
            "coordinates": [...]
          }
        }
      ]
    }
  },
  "exposureArea": {
    "type": "FeatureCollection",
    "name": "GeoJSON",
    "features": [
      {
        "type": "Feature",
        "geometry": {
          "type": "MultiPolygon",
          "coordinates": [...]
        },
        "properties": {
          "exposureLevel": 1
        }
      },
      {
        "type": "Feature",
        "geometry": {
          "type": "MultiPolygon",
          "coordinates": [...]
        },
        "properties": {
          "exposureLevel": 2
        }
      },
      {
        "type": "Feature",
        "geometry": {
          "type": "MultiPolygon",
          "coordinates": [...]
        },
        "properties": {
          "exposureLevel": 3
        }
      }
    ]
  }
}
```

{% hint style="info" %}
In this sample, coordinate arrays in `activeGeography.wkt`, `exposureArea`, and `pga_contours` geometries have been replaced with `[...]` or `(...truncated...)` for brevity. In actual API responses, these properties contain complete coordinate data. The `activeGeography.wkt.text` field contains a full WKT POLYGON string defining the smart alert boundary.
{% endhint %}


---

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