Quake

EQMag

Earthquake magnitude container object

EQLoc

QuakeML-compliant earthquake location

flags (0x01 = true, 0x00 = false)

1. x fixed?
2. y fixed?
3. z fixed?
4. t fixed?

EventChannel

A single channel of trace data (digital seismograms) associated with a discrete event (earthquake).

See EventTraceData

EventTraceData

A custom structure designed to describe trace data (digital seismograms) associated with a discrete event (earthquake).

EventChannel

A single channel of trace data (digital seismograms) associated with a discrete event (earthquake).

Fields: EventTraceData, EventChannel, SeisEvent.data

1. Not present in EventChannel objects.

See also: PhaseCat, SeisPha, SeisData

SeisEvent

A structure for discrete seismic events, comprising three structures:

• :hdr, a SeisHdr for the event descriptor
• :source, a SeisSrc for descrition of the seismic source process
• :data, an EventTraceData structure for channel data, including phases

See also: SeisHdr, SeisSrc, EventTraceData

SeisHdr: header information for seismic events

S = SeisHdr()

Initialize an empty SeisHdr object. Fields can be initialized at creation with keywords, e.g., SeisHdr(ot=DateTime("2012-01-03T03:49:45"), int=(0x02, "MMI")).

See also: EQLoc, EQMag

SeisPha()

IRIS-style seismic phase and pick container

SeisSrc: container for descriptions of a seismic source process

S = SeisSrc()

Initialize an empty SeisSrc object. Fields can be initialized at creation with keywords; for example, S = SeisSrc(m0 = 1.6e22).

See also: EQLoc, EQMag, SourceTime

SourceTime()

QuakeML-compliant seismic source-time parameterization.

(H,R) = FDSNevq(ot)

Multi-server query for the events with the closest origin time to ot. Returns an Array{SeisHdr,1} in H with event headers and an Array{SeisSrc,1} in R in H with corresponding source process info.

Keywords

1. Array{T, 1} for evw, mag, rad, reg; T for others
2. search range is always ot-|evw[1]| ≤ t ≤ ot+|evw[2]|
3. if nev=0, all matches are returned.
4. In an event query, keyword src can be a comma-delineated list, like "IRIS, INGV, NCEDC".

Notes

• Specify ot as a string formatted YYYY-MM-DDThh:mm:ss in UTC (e.g. "2001-02-08T18:54:32").
• Incomplete string queries are read to the nearest fully-specified time constraint; thus, FDSNevq("2001-02-08") returns the nearest event to 2001-02-08T00:00:00.
• If no event is found in the specified search window, FDSNevq exits with an error.
• For FDSNevq, keyword src can be a comma-delineated list of sources, provided each has a value in ?seis_www; for example, src="IRIS, INGV, NCEDC" is valid.

See also: SeisBase.KW, ?seis_www

FDSNevt(ot::String, chans::String)

Get header and trace data for the event closest to origin time ot on channels chans. Returns a SeisEvent structure.

Keywords

1. KW is Array{T, 1} for evw, mag, rad, reg, type T for others
2. Search range is always ot-|evw[1]| ≤ t ≤ ot+|evw[2]|
3. Format like an http request string, e.g. "szsrecs=true&repo=realtime" for FDSN. String shouldn't begin with an ampersand.
4. Comma-separated String, like "P, pP"; use "ttall" for all phases

Notes

• Specify ot as a string formatted YYYY-MM-DDThh:mm:ss in UTC (e.g. "2001-02-08T18:54:32").
• Incomplete string queries are read to the nearest fully-specified time constraint; thus, FDSNevq("2001-02-08") returns the nearest event to 2001-02-08T00:00:00.
• If no event is found in the specified search window, FDSNevt exits with an error.
• Unlike FDSNevq, number of events cannot be specified and src must be a single source String in ?seis_www.

See also: distaz!, FDSNevq, FDSNsta

get_pha!(Ev::SeisEvent[, keywords])

Command-line interface to IRIS online travel time calculator, which calls TauP [1-2]. Returns a matrix of strings.

Keywords:

• pha: comma-separated String of phases ("P, S, SP")
• model: velocity model ("iasp91")
• to: timeout in seconds
• v: verbosity

References

1. TauP manual: http://www.seis.sc.edu/downloads/TauP/taup.pdf
2. Crotwell, H. P., Owens, T. J., & Ritsema, J. (1999). The TauP Toolkit:

Flexible seismic travel-time and ray-path utilities, SRL 70(2), 154-160.

distaz!(Ev::SeisEvent)

Compute Δ, Θ by the Haversine formula.

Updates Ev.data with distance, azimuth, and backazimuth for each channel, written to Ev.data.dist, Ev.data.az, and Ev.data.baz, respectively.

G = gcdist(src, rec)

Compute great circle distance, azimuth, and backazimuth from single source s with coordinates [s_lat, s_lon] to receivers r with coordinates [r_lat r_lon].

For a single source, pass src as a Float64 vector of the form [s_lat, s_lon]; gcdist will return an Array{Float64,2} of the form

[Δ₁   θ₁   β₁
 Δ₂   θ₂   β₂
 ⋮    ⋮    ⋮
 Δn   θn   βn]

for receivers 1:n.

For multiple sources, pass src as an Array{Float64,2} with each row containing one (lat, lon) pair. This returns a three-dimensional matrix where each two-dimensional slice takes the form

  [Δᵢ₁   θᵢ₁   βᵢ₁
   ⋮     ⋮     ⋮
   Δᵢn   θᵢn   βᵢn]

for source i at receivers 1:n.

show_phases(io::IO, PC::PhaseCat)

Formatted display of seismic phases in dictionary P.

fill_sac_evh!(Ev::SeisEvent, fname::String; k=i)

Fill (overwrite) values in Ev.hdr with data from SAC file fname. Keyword k=i specifies the reference channel i from which the absolute origin time Ev.hdr.ot is set. Potentially affects header fields :id, :loc (subfields .lat, .lon, .dep), and :ot.

Ev = read_quake(fmt, file)

Read data in file format fmt from file into SeisEvent object Ev.

• Formats: suds, qml, uw
• Keywords: full, v

Note: because earthquake data are usually discrete, self-contained files, no "in-place" version of read_quake exists, and read_quake doesn't support wildcards in the file string.

Supported File Formats

See also: read_data, get_data, read_meta, UW.readuwevt