# USGS Earthquake Catalog Change Evidence API (`soilair/usgs-earthquake-catalog-change-evidence-api`) Actor

Read a bounded historical USGS event window with magnitude, coordinates, review status and source links. Change snapshots without prediction or emergency notifications.

- **URL**: https://apify.com/soilair/usgs-earthquake-catalog-change-evidence-api.md
- **Developed by:** [Salih Can Kurnaz](https://apify.com/soilair) (community)
- **Categories:** Education
- **Stats:** 2 total users, 1 monthly users, 93.3% runs succeeded, 0 bookmarks
- **User rating**: No ratings yet

## Pricing

from $0.70 / 1,000 catalog event observations

This Actor is paid per event. You are not charged for the Apify platform usage, but only a fixed price for specific events.

Learn more: https://docs.apify.com/actors/running/actors-in-store.md#pay-per-event

## What's an Apify Actor?

An Actor is a serverless cloud program that runs on the Apify platform. It has two run modes.
In Batch mode, an Actor accepts a well-defined JSON input, performs an action which can take anything from a few seconds to a few hours,
and optionally produces a well-defined JSON output, datasets with results, or files in key-value store.
In Standby mode, an Actor provides a web server which can be used as a website, API, or an MCP server.

Apify vocabulary and the platform model are defined once, in the agent quickstart at https://apify.com/agents.md.

## How to integrate an Actor?

If asked about integration, you help developers integrate Actors into their projects.
You adapt to their stack and deliver integrations that are safe, well-documented, and production-ready.

Do not guess an integration path. Every one of them is in the agent quickstart at https://apify.com/agents.md: the Apify MCP server, Agent Skills with the Apify CLI, the JavaScript and Python clients, the REST API, and the account-free path for an agent with no human to sign in. It also carries the rule on stating cost before the first paid run.

For examples already wired to this Actor's own input schema, see the [API](#api) section below.

Each client library has reference documentation the quickstart does not restate: [JavaScript/TypeScript](https://docs.apify.com/api/client/js/docs.md) (`npm install apify-client`) and [Python](https://docs.apify.com/api/client/python/docs.md) (`pip install apify-client`).

# README

## USGS Earthquake Catalog Change Evidence API

Read selected catalog metadata for a bounded historical event window. Returns USGS event ID, reported magnitude/type, event/update milliseconds, place, point coordinates/depth, review status and source URL. Intended for catalog QA, maps and historical data pipelines; not earthquake prediction, emergency dispatch or a push-alert service.

One official USGS FDSN GeoJSON query, date window1..31 days since1970, minMagnitude0..10 and at most50 events. Source order is descending origin time. No global history crawl, unbounded paging, earthquake forecasts, casualty/damage inference or notification. At the event cap, more results are unknown and complete=false; fewer results describe only the submitted filters, not absence of all earthquakes.204 No Content is a valid empty matching query;404/other errors are not empty data. Provider magnitude, coordinates, depth and review status are copied and can be revised. Timestamp values remain reported milliseconds; API date boundaries are not changed. Additional event/detail URLs are never fetched. No safety or scientific completeness guarantee beyond the selected query contract.

### Quick start

```json
{"startDate": "2025-01-01", "endDate": "2025-01-03", "minMagnitude": 4, "maxEvents": 2}
```

### Pricing and budget

0.0007 USD per emitted catalog event observation (0.7 USD per1000), plus0.005 USD startup at default256MB. Higher memory can multiply startup events; check effective Store pricing. Failed/empty sources do not emit result charges; startup can still apply. At zero result budget, input validation occurs but no upstream request is sent, and rowsAvailable is null (unknown). A positive budget can request the bounded source set before output; emission stops at the result cap and complete=false/PARTIAL_BUDGET reports truncation.

### Snapshot, integration and limits

Use dataset rows together with OUTPUT and SNAPSHOT. Pass SNAPSHOT.previousHashes as previousHashes in a later run. NO_BASELINE/FIRST_SEEN/UNCHANGED/CHANGED compare only selected metadata including itemKey and sourceUrl; missing records are not deletions. FIRST_SEEN means absent from the supplied baseline. There is no persistent hidden state or automatic polling. Export JSON/CSV/Excel through the default dataset.

API example: POST https://api.apify.com/v2/actors/soilair~usgs-earthquake-catalog-change-evidence-api/runs with your Apify Authorization header and the JSON input above. Poll the returned run; read dataset items and OUTPUT/SNAPSHOT records using its store IDs. Do not place tokens or confidential data in input. No upstream key is needed. Results live in Apify run storage according to retention; no separate analytics service.

Only fixed HTTPS provider endpoints are constructed from validated identifiers. Public-IP DNS validation, pinned connections, TLS hostname verification,2MiB decoded responses, approximately95 seconds of network budget, at most5 same-provider redirects. Official API calls are distinct from website crawling; no arbitrary URLs or HTML pages. No linked documents/files are fetched. Queries are sequential with1-second spacing. Provider403/429 or Retry-After stops later calls; retry instructions are reported and no retry/proxy/circumvention is attempted. Shared IP limits and changes to upstream services can still block runs. Caller must respect provider headers and cache/reduce repeated requests. Text is data and should not be executed.

Developed with AI assistance. Tests and live/cloud comparisons qualify the selected-field contract; they do not prove commercial demand, provider uptime or a legal/license determination. Support: share a run ID and expected fields, without credentials or private material.

References: https://earthquake.usgs.gov/fdsnws/event/1/

# Actor input Schema

## `startDate` (type: `string`):

ISO YYYY-MM-DD on or after1970; interpreted by USGS in UTC.

## `endDate` (type: `string`):

ISO YYYY-MM-DD,1..31 days after start; passed to USGS without altering its time-boundary semantics.

## `minMagnitude` (type: `number`):

Finite numeric threshold0..10; reported magnitudes are not predictions.

## `maxEvents` (type: `integer`):

1..50 recent matching events in source order; hitting cap makes completeness unknown.

## `previousHashes` (type: `object`):

At most500 itemKey/SHA256 mappings; missing records are not deletion evidence.

## Actor input object example

```json
{
  "startDate": "2025-01-01",
  "endDate": "2025-01-03",
  "minMagnitude": 4,
  "maxEvents": 20,
  "previousHashes": {}
}
```

# Actor output Schema

## `results` (type: `string`):

No description

## `summary` (type: `string`):

No description

## `snapshot` (type: `string`):

No description

# API

You can run this Actor programmatically using our API. Below are code examples in JavaScript, Python, and CLI, as well as the OpenAPI specification and MCP server setup.

## JavaScript example

```javascript
import { ApifyClient } from 'apify-client';

// Initialize the ApifyClient with your Apify API token
// Replace the '<YOUR_API_TOKEN>' with your token
const client = new ApifyClient({
    token: '<YOUR_API_TOKEN>',
});

// Prepare Actor input
const input = {
    "startDate": "2025-01-01",
    "endDate": "2025-01-03"
};

// Run the Actor and wait for it to finish
const run = await client.actor("soilair/usgs-earthquake-catalog-change-evidence-api").call(input);

// Fetch and print Actor results from the run's dataset (if any)
console.log('Results from dataset');
console.log(`💾 Check your data here: https://console.apify.com/storage/datasets/${run.defaultDatasetId}`);
const { items } = await client.dataset(run.defaultDatasetId).listItems();
items.forEach((item) => {
    console.dir(item);
});

// 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/js/docs

```

## Python example

```python
from apify_client import ApifyClient

# Initialize the ApifyClient with your Apify API token
# Replace '<YOUR_API_TOKEN>' with your token.
client = ApifyClient("<YOUR_API_TOKEN>")

# Prepare the Actor input
run_input = {
    "startDate": "2025-01-01",
    "endDate": "2025-01-03",
}

# Run the Actor and wait for it to finish
run = client.actor("soilair/usgs-earthquake-catalog-change-evidence-api").call(run_input=run_input)

# Fetch and print Actor results from the run's dataset (if there are any)
print(f"💾 Check your data here: https://console.apify.com/storage/datasets/{run.default_dataset_id}")
for item in client.dataset(run.default_dataset_id).iterate_items():
    print(item)

# 📚 Want to learn more 📖? Go to → https://docs.apify.com/api/client/python/docs/quick-start

```

## CLI example

```bash
echo '{
  "startDate": "2025-01-01",
  "endDate": "2025-01-03"
}' |
apify call soilair/usgs-earthquake-catalog-change-evidence-api --silent --output-dataset

```

## MCP server setup

```json
{
    "mcpServers": {
        "apify": {
            "type": "http",
            "url": "https://mcp.apify.com/?tools=fetch-actor-details,soilair/usgs-earthquake-catalog-change-evidence-api"
        }
    }
}
```

The hosted server signs you in with OAuth on first connect, so no API token belongs in this config. Clients without OAuth support can send an `Authorization: Bearer <APIFY_API_TOKEN>` header instead, using a token from API & Integrations in Apify Console (https://console.apify.com/settings/integrations).

## OpenAPI specification

Download the OpenAPI definition: https://api.apify.com/v2/actors/cePpnEfKo15IVfgBe/builds/XNG91Me8JpLPtgUvO/openapi.json