Create an earthquake Item¶

Install the package using the installation guide. The following example uses synthetic event data.

Create and extend an Item¶

from datetime import datetime, timezone

import pystac
from pystac.extensions.earthquake import EarthquakeExtension

item = pystac.Item(
    id="example-earthquake",
    geometry={"type": "Point", "coordinates": [12.5, 42.0]},
    bbox=[12.5, 42.0, 12.5, 42.0],
    datetime=datetime(2026, 1, 1, tzinfo=timezone.utc),
    properties={"title": "Synthetic earthquake example"},
)
earthquake = EarthquakeExtension.ext(item, add_if_missing=True)
earthquake.apply(
    magnitude=6.1,
    magnitude_type="mww",
    sources=[{"name": "example-network", "code": "event-001"}],
    felt=12,
    status="reviewed",
    tsunami=False,
    depth=8.4,
)

assert earthquake.magnitude == 6.1
assert item.properties["eq:depth"] == 8.4
assert EarthquakeExtension.get_schema_uri() in item.stac_extensions

Coordinates use longitude, latitude order. depth is expressed in kilometers. add_if_missing=True adds the extension identifier to the Item. The wrapper mutates the Item in place.

Serialize and read back¶

Continue in the same Python session:

import json

payload = item.to_dict()
print(json.dumps(payload, indent=2))
restored_item = pystac.Item.from_dict(payload)
restored = EarthquakeExtension.ext(restored_item)
assert restored.sources == earthquake.sources

Serialization does not perform JSON Schema validation. See validation boundaries for the distinction between setter checks and full document validation.

Use individual setters for partial updates: apply() also clears optional fields whose arguments are omitted.