### phaseRequest

This generates requests based on the times relative to calculated phase arrivals. See the documentation for the TauP Toolkit, http://www.seis.sc.edu/TauP for the phase naming convention. SOD uses the TauP Toolkit internally. The begin and end phase can be a comma separated list. If there are multiple arrivals for the phases, then the time will be calculated relative to the first arriving phase. If there are zero arrivals for the phases, then no request will be generated and no data will be retrieved. The phase name "origin" may be used to express an offset from the origin time.

### Example

    <phaseRequest>
      <beginPhase>ttp</beginPhase>
      <beginOffset>
          <unit>SECOND</unit>
          <value>-60</value>
      </beginOffset>
      <endPhase>ttp</endPhase>
      <endOffset>
          <unit>SECOND</unit>
          <value>360</value>
      </endOffset>
    </phaseRequest>

### This consists of

<phaseRequest>

<model> optional
model choice
1066a
1066b
ak135
alfs
herrin
iasp91
jb
prem
pwdk
qdt
sp6
</model>
<beginPhase>phaseName</beginPhase>
<beginOffset>
choice
randomOffset
timeInterval
</beginOffset>
<endPhase>phaseName</endPhase>
<endOffset>
choice
randomOffset
timeInterval
</endOffset>
</phaseRequest>

### Places this can be found

In requestGenerator there is a choice between all of the following

- phaseRequest
- originOffsetRequest
- choiceRequest
- combineRequest
- requestGeneratorScript