anss-formats 0.1.0

Python implementation of the library used to communicate seismic event detection information between systems

ANSS Data Formats

This is the Python implementation of the library used to generate and parse the ANSS Formats.

Dependencies

• ANSS Formats utilizes JSON for formatting.
• ANSS Formats was written in Python 3.6
• ANSS Formats uses poetry for Package, dependency and environment management.

The US Geological Survey (USGS) Advanced National Seismic System (ANSS) defines a number of data exchange formats to communicate seismic event detection information between processing systems. These formats are defined using objects as defined in the JSON standard.

The purpose of this project is to:

1. Define formats to hold data representing the estimates of various types of seismic event detections.
2. Store the format definitions in a source controlled manner.
3. Host libraries used to generate, parse, and validate the formats

Defined formats:

• Pick Format - A format for unassociated picks from a waveform arrival time picking algorithm.
• Detection Format - A format for an earthquake detection picks from a seismic detection algorithm.

Supporting format objects:

• Amplitude Object - An object that contains information about an amplitude as part of a pick.
• Associated Object - An object that contains associated information if a pick is included in a detection.
• Channel Object - A geoJSON object that contains channel/location information as part of a pick.
• EventType Object - An object that defines the event type for MachineLearning info.
• Filter Object - An object that contains filter information as part of a pick.
• Hypocenter Object - A geoJSON object that contains the hypocentral location, arrival time, and error information as part of a detection.
• MachineLearning Object - An object that defines the machine learning information for a pick.
• Magnitude Object - An object that defines an earthquake magnitude estimation, as part of a Machine Learning classification or earthquake detection.
• Quality Object - An object that defines the data quality of a pick.
• Source Object - An object that defines the creator/source of a pick.

Amplitude Object Specification

Description

The Amplitude object is an object designed to encode the amplitude information that may or may not be part of the Pick Format. Amplitude uses the JSON standard.

Usage

The Amplitude object is intended for use as part of the Pick Format in seismic data messaging between seismic applications and organizations.

Output

    {
       "amplitude" : Number,
       "period"    : Number,
       "snr"       : Number
    }

Glossary

Optional Values:

The following are values that may or may not be provided as part of an amplitude.

• amplitude - A decimal number containing the amplitude.
• period - A decimal number containing the amplitude period.
• snr - A decimal number containing the signal to noise ratio, capped at 1E9.

Association Object Specification

Description

The Association object is an object designed to encode information provided when a Pick. Association uses the JSON standard.

Usage

Association is intended for use as part of the Pick Format in seismic data messaging between seismic applications and organizations.

Output

    {
       "phase"    : String,
       "distance" : Number,
       "azimuth"  : Number,
       "residual" : Number,
       "sigma"    : Number
    }

Glossary

Optional Values:

The following are values that may or may not be provided as part of association.

• phase - A string that identifies the seismic phase for this data if Association.
• distance - A decimal number containing the distance in degrees between the detection's and data's locations if Association.
• azimuth - A decimal number containing the azimuth in degrees between the detection's and data's locations if Association.
• residual - A decimal number containing residual in seconds of the data if Association.
• sigma - A decimal number reflecting the number of standard deviations of the data from the calculated value if Association.

Site Object Specification

Description

The Site object is an object designed to define the seismic station used to produce a Pick message. Site uses the JSON and GeoJSON standards.

Usage

Site is intended for use as part of the Pick Format in seismic data messaging between seismic applications and organizations.

Output

{
  "type": "Feature",
  "geometry": {
    "type": "Point",
    "coordinates": [125.6, 10.1]
  },
  "properties": {
    "station"   : String,
    "channel"   : String,
    "network"   : String,
    "location"  : String
  }
}

Glossary

Required Values:

These are the properties required to define a Site.

• type - A string indicating the geojson feature type
• geometry - A geojson point containing the station coordinates in the form [Latitude, Longitude, Elevation (in meters)]
• properties - The associated properties for this geojson feature

Required Properties:

These geojson feature properties are required to define a Site.

• station - A string the station code.
• network - A string containing network code.

Optional Properties:

The following are supplementary geojson feature properties that may or may not be provided by various algorithms.

• channel - A string containing the channel code.
• location - A string containing the location code.

Detection Format Specification

Description

Detection is a format designed to encode the basic information of an earthquake event Detection. Detection uses the JSON standard.

Usage

Detection is intended for use in seismic data messaging between seismic applications.

Output

    {
      "type"        : "Detection",
      "id"          : String,
      "source"      :
      {
         "agencyID" : String,
         "author"   : String
      },
      "hypocenter"  :
        {
          "type": "Feature",
          "geometry": {
            "type": "Point",
            "coordinates": [125.6, 10.1, 1589.0]
        },
          "properties": {
            "originTime"      : ISO8601,
            "latitudeError"   : Number,
            "longitudeError"  : Number,
            "depthError"      : Number,
            "originTimeError" : Number
        }      
      },
      "detectionType"   : String,
      "detectionTime"   : ISO8601,
      "eventType" :
      {
          "type"      : String,
          "certainty" : String
      },
      "minimumDistance" : Number,
      "rms"             : Number,
      "maximumGap"      : Number,
      "detector"        : String,
      "pickData"  : [Pick Objects],
      "magnitudeData" :
      [ 
        {
          "type" : String,
          "id" : String,
          "value" : Number,
          "source" :
          {
            "agencyID" : String,
            "author"   : String
          },  
          "error" : Number,
          "probability" : Number
        }, ...
      ]
    }

Glossary

Required Values:

These are the values required to define a detection.

• type - A string that identifies this message as a detection.
• id - A string containing an unique identifier for this Detection.
• source - An object containing the source of the Detection, see Source.
• hypocenter - An object containing the hypocenter of the Detection, see Hypocenter.

Optional Values:

The following are supplementary values that may or may not be provided as part of a detection.

• detectionType - A string that identifies whether the Detection is New, Update, or Final.
• detectionTime - A string containing the UTC time this detection was made, i.e. how quickly after origin time was this detection created, in the ISO8601 format YYYY-MM-DDTHH:MM:SS.SSSZ.
• eventType - An object containing the event type of the correlation, see EventType.
• rms - A decimal number containing the rms estimate for the detction
• minimumDistance - A decimal number representing the minimum distance to the closest supporting station.
• maximumGap - A decimal number representing the maximum gap in degrees between supporting stations.
• detector - A string identifying the detection grid, algorithm, or other information.
• pickData - An array of Pick objects used to generate this Detection.
• magnitudeData - An array of Magnitude objects for this Detection.

EventType Object Specification

Description

The EventType object is an object designed to define the originating seismic organization that produced a MachineLearning object. Site uses the JSON standard.

Usage

EventType is intended for use as part of the PicMachineLearningk Oject in seismic data messaging between seismic applications and organizations.

Output

    {
      "type"  : String,
      "certainty"    : String
    }

Glossary

Required Values:

These are the values required to define a EventType

• type - A string containing the event type, allowed type strings are: "Earthquake", "MineCollapse", "NuclearExplosion", "QuarryBlast", "InducedOrTriggered", "RockBurst", "FluidInjection", "IceQuake", and "VolcanicEruption"

Optional Values:

The following are values that may or may not be provided as part of EventType.

• certainty - A string containing the certainty of the event type; allowed strings are "Suspected" and "Confirmed"

Filter Object Specification

Description

The Filter object is an object designed to encode a single set of filter frequencies that may or may not be part of the filter list in the Pick Format. Filter uses the JSON standard .

Usage

The Filter object is intended for use as part of the Pick Format in seismic data messaging between seismic applications and organizations.

Output

   {
      "type"     : String,
      "highPass" : Number,
      "lowPass"  : Number,
      "units"    : String
   }

Glossary

Optional Values:

The following are values that may or may not be provided as part of a filter.

• type - A string containing the type of filter
• highPass - A decimal number containing the high pass frequency in Hz.
• lowPass - A decimal number containing the low pass frequency in Hz.
• units - A string containing the filter frequency units.

Note: The Type of filter is assumed to be "BandPass", and the Units are assumed to be "Hertz"

Hypocenter Object Specification

Description

The Hypocenter object is an object designed to define a Hypocenter as part of a Detection message. Hypocenter uses the JSON standard and GeoJSON standards.

Usage

Hypocenter is intended for use as part of the Detection Format in seismic data messaging between seismic applications and organizations.

Output

    {
      "type": "Feature",
      "geometry": {
        "type": "Point",
        "coordinates": [125.6, 10.1, 1589.0]
      },
      "properties": {
        "originTime"      : ISO8601,
        "latitudeError"   : Number,
        "longitudeError"  : Number,
        "depthError"      : Number,
        "originTimeError" : Number
      }      
    }

Glossary

Required Values:

These are the values required to define a hypocenter.

• type - A string indicating the geojson feature type, always a point
• geometry - A geojson point containing the station coordinates in the form [Latitude, Longitude, Depth (in meters)]
• properties - The associated properties for this geojson feature

Required Properties:

These geojson feature properties are required to define a hypocenter.

• originTime - A string containing the UTC origin time of this hypocenter, in the ISO8601 format YYYY-MM-DDTHH:MM:SS.SSSZ.

Optional Properties:

The following are supplementary geojson feature properties that may or may not be provided by various algorithms.

• latitudeError - A decimal number that identifies the error of the latitude of this hypocenter in kilometers.
• longitudeError - A decimal number that identifies the error of the longitude of this hypocenter in kilometers.
• depthError - A decimal number that identifies the depth error of this hypocenter in kilometers.
• originTimeError - A decimal number that identifies the error of the origin time in seconds.

MachineLearning Object Specification

Description

The MachineLearning object is an object designed to encode value added information available for a Pick from advanced algorithms such as machine learning. MachineLearning uses the JSON standard.

Usage

MachineLearning is intended for use as part of the Pick Format in seismic data messaging between seismic applications and organizations.

Output

    {
        "phase"                : String,
        "phaseProbability"     : Number,
        "distance"             : Number,
        "distanceProbability"  : Number,
        "distanceRangeHalfWidth"   : Number,
        "distanceRangeSigma"       : Number,
        "backAzimuth"              : Number,
        "backAzimuthProbability"   : Number,
        "magnitude" :
        {
            "type" : String,
            "id" : String,
            "value" : Number,
            "source" :
            {
                "agencyID" : String,
                "author"   : String
            },  
            "error" : Number,
            "probability" : Number
        }, 
        "depth"                : Number,
        "depthProbability"     : Number,
        "eventType" :
        {
            "type"      : String,
            "certainty" : String
        },
        "eventTypeProbability" : Number,
        "repickShift" : Number,
        "repickSTD" : Number,
        "repickCredibleIntervalLower" : Number,
        "repickCredibleIntervalUpper" : Number,
        "source" :
        {
            "agencyID" : String,
            "author"   : String
        }
    }

Glossary

Optional Values:

The following are values that may or may not be provided as part of MachineLearning.

• phase - A string that identifies the seismic phase for this data
• phaseProbability - A decimal number containing the probability of the phase identification
• distance - A decimal number containing a distance estimation in degrees
• distanceProbability - A decimal number containing the probability of the distance estimation
• distanceRangeHalfWidth - A decimal number containing the half-width of a distance range centered at Distance (e.g. Distance is 15 deg +/- 10 deg)
• distanceRangeSigma - A decimal number containing the standard deviation for a probability PDF curve for Distance (e.g. Distance is 15 deg +/- 3 * DistanceRangeSigma where DistanceProbability is modified by the PDF probability, lowering as it gets further from Distance ). DistanceRangeSigma is mutually exclusive of DistanceRangeHalfWidth, and if both are provided DistanceRangeSigma should be used.
• backAzimuth - A decimal number containing a backazimuth estimation in degrees
• backAzimuthProbability - A decimal number containing the probability of the backazimuth estimation
• magnitude - A Magnitude object containing the machine learning magnitude estimation
• depth - A decimal number containing a depth estimation in kilometers
• depthProbability - A decimal number containing the probability of the depth estimation
• eventType - An object containing the event type, see EventType.
• eventTypeProbability - A decimal number containing the probability of the event type estimation
• repickShift - A decimal number containing the repick shift in seconds (to regenerate the initial Pick.Time, subtract this value from the current Pick.Time)
• repickSTD - A decimal number containing the repick shift standard deviation
• repickCredibleIntervalLower - A decimal number containing the repick shift credible interval lower
• repickCredibleIntervalUpper - A decimal number containing the repick shift credible interval upper
• source - An object containing the source of the MachineLearning, see Source.

Magnitude Object Specification

Description

The Magnitude object is an object designed to hold data quality for a Detection message. Site uses the JSON standard.

Usage

Magnitude is intended for use as part of the Detection Format in seismic data messaging between seismic applications and organizations.

Output

    {
      "type" : String,
      "id" : String,
      "value" : Number,
      "source" :
      {
         "agencyID" : String,
         "author"   : String
      },  
      "error" : Number,
      "probability" : Number
    }

Glossary

Required Values:

These are the values required to define a Magnitude

• type - A string containing the name of the magnitude type.
• value - A decimal number containing numarical value of the magnitude.

Optional Values:

The following are supplementary values that may or may not be provided as part of a Magnitude.

• id - A string containing an unique identifier for this Magnitude.
• source - An object containing the source of the Magnitude, see Source.
• error - A decimal number containing numarical error estimate of the magnitude.
• probability - A decimal number containing the probability of the magnitude

Pick Format Specification

Description

Pick is a format designed to encode the basic information of an unassociated waveform arrival time pick. Pick uses the JSON standard.

Usage

Pick is intended for use in seismic data messaging between seismic applications and organizations.

Output

    {
      "type"      : "Pick",
      "id"        : String,
      "channel"      :
      {
        "type": "Feature",
        "geometry": {
          "type": "Point",
          "coordinates": [125.6, 10.1, 1589.0]
        },
        "properties": {
          "station"   : String,
          "channel"   : String,
          "network"   : String,
          "location"  : String
        }
      },
      "time"      : ISO8601,
      "source"    :
      {
         "agencyID"  : String,
         "author"    : String
      },
      "phase"     : String,
      "polarity"  : ("up" | "down"),
      "onset"     : ("impulsive" | "emergent" | "questionable"),
      "pickerType"    : ("manual" | "raypicker" | "filterpicker" | "earthworm" | "other"),
      "filterInfo"    : [ {
        "type"     : String,
        "highPass" : Number,
        "lowPass"  : Number,
        "units"    : String
        }, ...],
      "amplitudeInfo" :
      {
         "value" : Number,
         "period"    : Number,
         "snr"       : Number
      },
      "associationInfo" :
      {
         "phase"    : String,
         "distance" : Number,
         "azimuth"  : Number,
         "residual" : Number,
         "sigma"    : Number
      },
      "qualityInfo" : [ {
        "standard": String,
        "value": Number
        }, ...],
      "machineLearningInfo" :
      {
        "phase"                : String,
        "phaseProbability"     : Number,
        "distance"             : Number,
        "distanceProbability"  : Number,
        "distanceRangeHalfWidth"   : Number,
        "distanceRangeSigma"       : Number,
        "backAzimuth"              : Number,
        "backAzimuthProbability"   : Number,
        "magnitude" :
        {
          "type" : String,
          "id" : String,
          "value" : Number,
          "source" :
          {
            "agencyID" : String,
            "author"   : String
          },  
          "error" : Number,
          "probability" : Number
        },
        "depth"                : Number,
        "depthProbability"     : Number,
        "eventType" : {
          "type"      : String,
          "certainty" : String
        },
        "eventTypeProbability" : Number,
        "repickShift" : Number,
        "repickSTD" : Number,
        "repickCredibleIntervalLower" : Number,
        "repickCredibleIntervalUpper" : Number,
        "source" : {
            "agencyID" : String,
            "author"   : String
        }
      }
    }

Glossary

Required Values:

These are the values required to define a pick.

• type - A string that identifies this message as a pick.
• id - A string containing an unique identifier for this pick.
• channel - A GeoJSON object containing the channel the pick was made at, see Channel.
• source - An object containing the source of the pick, see Source.
• time - A string containing the UTC arrival time of the phase that was picked, in the ISO8601 format YYYY-MM-DDTHH:MM:SS.SSSZ.

Optional Values:

The following are supplementary values that may or may not be provided by various picking algorithms.

• phase - A string that identifies the seismic phase that was picked.
• polarity - A string containing the phase polarity; "up" or "down".
• onset - A string containing the phase onset; "impulsive", "emergent", or "questionable" .
• pickerType - A string describing the type of picker; "manual", "raypicker", "filterpicker", "earthworm", or "other".
• filter - An array of objects containing the filter frequencies when the pick was made, see Filter.
• amplitude - An object containing the amplitude associated with the pick, see Amplitude.
• associationInfo - An object containing the association information if this pick is used as data in a Detection, see Associated.
• machineLearningInfo - An object containing the machine learning information of this pick, see MachineLearning.
• qualityInfo - An array of objects containing the containing the quality metric information for this pick, see Quality.

Quality Object Specification

Description

The Quality object is an object designed to hold data quality for a Pick message. Site uses the JSON standard.

Usage

Quality is intended for use as part of the Pick Format in seismic data messaging between seismic applications and organizations.

Output

    {
        "standard": String,
        "value": Number
    }

Glossary

Required Values:

These are the values required to define a Quality

• standard - A string containing the name of the quality standard.
• value - A string containing numarical value of the quality standard.

Source Object Specification

Description

The Source object is an object designed to define the originating seismic organization that produced a Pick message. Site uses the JSON standard.

Usage

Source is intended for use as part of the Pick Format in seismic data messaging between seismic applications and organizations.

Output

    {
      "agencyID"  : String,
      "author"    : String
    }

Glossary

Required Values:

These are the values required to define a Source

• agencyID - A string containing the originating agency FDSN ID.
• author - A string containing the source author.