Events Based
===========

This workflow begins with selecting earthquake events and then finding stations that recorded those events.

Overview
--------

The Events Based workflow is designed for analyses that start with specific earthquake events of interest. This approach is ideal for studying particular earthquakes and their recordings across multiple stations.

Workflow Steps
-------------

1. **Select Events**: Choose earthquake events based on criteria such as time range, magnitude, and geographic location
2. **Select Stations**: Choose seismic stations that recorded the selected events
3. **Download Waveforms**: Retrieve waveform data for the selected event-station pairs

Step 1: Search & Select Events
----------------------------

.. figure:: ../screenshots/event-based.png
   :alt: Event Selection Interface
   :width: 100%
   
   Event selection interface showing map and filtering options

The event selection interface allows you to search for and select earthquake events using various criteria:

.. include:: ../shared/map_interface.rst
   :start-after: Map Interface
   :end-before: **Rectangle Selection**

**Filtering Options**:
   * **FDSN Client**: Select a data provider (e.g., EARTHSCOPE)

.. include:: ../shared/time_filters.rst
   :start-after: Time Filtering
   :end-before: **Time (UTC) Selection**

   * **Magnitude Range**: Use the slider to set minimum and maximum magnitude values (e.g., 5.20 to 7.10)
   * **Depth Range (km)**: Use the slider to set minimum and maximum depth values
   * Note that marker size on the map is associated with earthquake magnitude (larger markers = stronger earthquakes)

.. include:: ../shared/selection_tables.rst
   :start-after: Selection Tables
   :end-before: **Import/Export**

   * Event details shown include location, magnitude, magnitude type, time, coordinates, and depth

.. include:: ../shared/selection_tables.rst
   :start-after: **Import/Export**

After selecting your events, click the "Next" button to proceed to the next step in the workflow.

Step 2: Select Stations
---------------------

After selecting earthquake events, the next step is to choose seismic stations that recorded these events.

The station selection interface for the events-based workflow is similar to the one in the station-based workflow, but with an important difference: the stations shown are filtered to only include those that have recorded the events you selected in Step 1.

**Station Filtering Options**:
   * **FDSN Client**: Select a data provider (e.g., EARTHSCOPE)
   * **Network**: Filter by seismic network code
   * **Station**: Filter by specific station codes
   * **Location**: Filter by location codes
   * **Channel**: Filter by channel codes
   * **Additional Options**: 
     * Toggle "Highest Sample Rate Only" to limit results
     * Include restricted data if you have appropriate credentials

**Station Selection**:
   * View stations in the table that have recorded your selected events
   * Select individual stations using checkboxes
   * Use "Select All" or "Unselect All" buttons to quickly manage selections
   * Station details shown include network, station code, description, coordinates, and elevation

After selecting your stations, click the "Next" button to proceed to the final step in the workflow.

Step 3: Download & Analyze Waveforms
----------------------------------

.. figure:: ../screenshots/waveform.png
   :alt: Waveform Download and Analysis Interface
   :width: 100%
   
   Waveform download and analysis interface showing controls and visualization

The waveform download and analysis interface allows you to retrieve, view, and analyze seismic waveform data for your selected events and stations:

.. include:: ../shared/waveform_controls.rst
   :start-after: Waveform Controls
   :end-before: **Retrieval Controls**

**Waveform Analysis**:
   * Toggle between Waveform View and Log View
   * Use "Get Waveforms" button to retrieve data
   * "Force Re-download" option to bypass cache
   * View success messages (e.g., "Successfully retrieved waveforms for 810 channels")
   * Select view type:
     * Single Event - Multiple Stations (shown in screenshot)
     * Single Station - Multiple Events
   * Select specific events from dropdown menu
   * View waveform visualizations with color-coded channels
   * Download visualizations as PNG images

**Navigation**:
   * Page through multiple waveforms using the page navigation controls
   * Reset filters to start a new search
   * View total number of waveforms retrieved

This step completes the Events Based workflow, providing you with the waveform data needed for your analysis.

This workflow is particularly useful for:

* Studying specific earthquakes of interest
* Analyzing how a particular event was recorded at different stations
* Creating event-centered datasets for research

Key Features
-----------

* Event-driven processing architecture
* Configurable event selection criteria
* Station filtering based on event coverage
* Batch waveform downloading for multiple event-station pairs
* Event metadata visualization and export