HyFI Processing Workflows

HyFI supports two main processing workflows: Single-Sequence and Multi-Sequence processing. Each workflow is suited for different analysis scenarios and catalog complexities.

Single-Sequence Processing

Single-sequence processing analyzes all hypocenters in your catalog as one continuous seismic sequence. This is the standard workflow for analyzing a single earthquake swarm, cluster, or seismically active area.

When to Use Single-Sequence Processing

Analyzing a well-defined earthquake cluster or swarm
Working with pre-filtered or already segmented seismic catalogs
Studying a specific fault zone or localized seismicity

Configuration Structure

To set up a single-sequence HyFI analysis, the user has to configure the HyFI Input Parameters using the single-sequence workflow DAG configuration structure. For detailed information on the structure of the configuration DAG please see the HyFI Configuration.

Running Single-Sequence Analysis

Once the configuration file with the proper structure is setup and saved in JSON format, single-sequence processing can be started with:

hyfi run -c config_single_TEMPLATE.json

This will create a new directory as specified in the configuration file where all HyFI Output in the single-sequence format is saved to.

Multi-Sequence Processing

Multi-sequence processing segments your catalog into distinct seismic sequences based on spatial, temporal, or spatiotemporal clustering, then analyzes each sequence independently. This is ideal for large-scale, complex, and noisy catalogs with multiple distinct earthquake clusters or regions.

When to Use Multi-Sequence Processing

Large catalogs covering extensive spatial regions
Catalogs containing multiple distinct earthquake clusters
Analyzing seismicity from multiple fault systems simultaneously
Hierarchical analysis with different clustering scales
Complex regional seismicity requiring segmentation

Multi-Sequence Processing Explained

The segmentation process works hierarchically:

Step 1: Data Loading: Loading the full hypocenter catalog, incorporating multiple earthquake sequences.
Step 2: Multi-Step Catalog Segmentation: The hypocenter catalog is first divided into distinct sequences using clustering algorithms (DBSCAN, HDBSCAN, etc.). For this, multiple sequential clustering layers can be defined, where outliers from one step are passed to the next step with different parameters (e.g., tight clustering for Class A events, relaxed clustering for Class B events).
Step 3: Per-Sequence Analysis: Each segmented sequence is then analyzed independently with the full HyFI workflow (fault network reconstruction, classification, stress analysis, etc.).
Step 4: Merge into HyFI Database: Finally, the results of the individually processed clusters are merged into a common HyFI Database, incorporating metadata of identified faults, visualizations etc.

Configuration Structure

To set up a multi-sequence HyFI analysis, the user has to configure the HyFI Input Parameters using the multi-sequence workflow DAG configuration structure. For detailed information on the structure of the configuration DAG please see the HyFI Configuration.

Running Multi-Sequence Analysis

Once the configuration file with the proper structure is setup and saved in JSON format, multi-sequence processing can be started with:

hyfi run -c config_multi_TEMPLATE.json

This will create a new directory as specified in the configuration file where all HyFI Output in the multi-sequence format is saved to. Note that the multi-sequence outputs incorporates a nested structure of the individually processed clusters.

Happy fault imaging! 🎉