ETAS (version 0.4.9)

search.isc: Retrieving data from the ISC Bulletin

Description

Searches the International Seismological Centre (ISC) bulletin for recorded eqrthqukes ocurred during a specified time period in a specified geographical region (rectangular or circular) with a specified magnitude type and magnitude threshould.

Usage

search.isc(start.year=1900, start.month=1, start.day=01,
             end.year=2018, end.month=12, end.day=31,
             searchshape="RECT", lat.bot=NULL, lat.top=NULL,
             long.left=NULL, long.right=NULL, lat.ctr=NULL, 
             long.ctr=NULL, radius=NULL, dist.units="deg", 
             dep.min=0, dep.max=100, nulldep=TRUE,
             mag.min=4, mag.max=NULL, mag.type='MB', 
             mag.agcy=NULL, mirror=TRUE)

Arguments

start.year

A single numeric value specifying the start year of the time period.

start.month

A single numeric value (1 to 12) specifying the start month of the time period.

start.day

A single numeric value (1 to 31) specifying the start day of the time period.

end.year

A single numeric value specifying the end year of the time period.

end.month

A single numeric value (1 to 12) specifying the end month of the time period.

end.day

A single numeric value (1 to 31) specifying the end day of the time period.

searchshape

A character string specifying the shape of the search region. Rectangular search with searchshape="RECT" (default) and circular search searchshape="CIRC" are possible.

lat.bot

A single numeric value (-90 to 90) specifying the bottom latitude of the rectangular search region (if searchshape="RECT").

lat.top

A single numeric value (-90 to 90) specifying the top latitude of the rectangular search region (if searchshape="RECT").

long.left

A single numeric value (-180 to 180) specifying the left longitude of the rectangular search region (if searchshape="RECT").

long.right

A single numeric value (-180 to 180) specifying the right longitude of the rectangular search region (if searchshape="RECT").

lat.ctr

A single numeric value (-90 to 90) specifying the central latitude of the circular search region (if searchshape="CIRC").

long.ctr

A single numeric value (-180 to 180) specifying the central longitude of the circular search region (if searchshape="CIRC").

radius

A single numeric value specifying the search radius of the circular search region (if searchshape="CIRC").

dist.units

A character string specifying the unit of the search radius: degrees with "deg" and kilometers with "km" are the available options.

dep.min

A single numeric value specifying the minumum depth (km).

dep.max

A single numeric value specifying the maximum depth (km).

nulldep

Logical flag indicating whether to include events with unknown depths.

mag.min

A single numeric value specifying the minumum magnitude.

mag.max

A single numeric value specifying the maximum magnitude.

mag.type

A character string specifying the magnitude type. Due to the large number of magnitude types and the various notation used, the selected type will search all magnitudes of that type. E.g. the default "MB" will match all body-wave magnitudes: mb, mB, MB, mb1mx, etc.

mag.agcy

A character string specifying the magnitude author. "ISC", "NEIC", "GCMT/HRVD", "JMA", amongst others are considered reliable magnitude authors. The default uses "Any", which will match any author that has a magnitude for both prime and secondary hypocentres included in an event. Selecting "prime author" will limit the search by magnitudes directly associated with the prime hypocentre (usually the same author as the prime hypocentre) - i.e. for events with an ISC authored prime hypocentre, selecting 'Prime author', will limit events to those with ISC determined magnitudes.

mirror

Logical flag indicating whether to use the ISC mirror server hosted at IRIS DMC (http://isc-mirror.iris.washington.edu) as it may be faster.

Value

An object of class "data.frame" which can be passed to the "catalog" function in order to create an earthquake catalog dataset.

Details

Any use of data from the ISC by academic or commercial organisations, as well as individuals should always be cited. The correct format for citations may be found on http://www.isc.ac.uk/citations/.

The ISC is named as a valid data centre for citations within American Geophysical Union (AGU) publications. As such, please follow the AGU guidelines when referencing ISC data in one of their journals. The ISC may be cited as both the institutional author of the Bulletin and the source from which the data were retrieved.

References

International Seismological Centre (2015). On-line Bulletin, http://www.isc.ac.uk, Internatl. Seismol. Cent., Thatcham, United Kingdom.

International Seismological Centre (2015). Reference Event Bulletin, http://www.isc.ac.uk, Internatl. Seismol. Cent., Thatcham, United Kingdom.

International Seismological Centre (2015). EHB Bulletin, http://www.isc.ac.uk, Internatl. Seismol. Cent., Thatcham, United Kingdom.

See Also

catalog.

Examples

# NOT RUN {
  
  # rectangular search
  
# }
# NOT RUN {
  mydata <- search.isc(start.year=1980, start.month=1, start.day=01,
                   end.year=2017, end.month=11, end.day=11, 
                   lat.bot=33, lat.top=37,
                   long.left=44, long.right=48,
                   mag.min=3.5, mag.type='MB')  
  mycatalog <- catalog(mydata, study.start = "1990-01-01")
  plot(mycatalog)
  
# }
# NOT RUN {
  # circular search
  
# }
# NOT RUN {
  mydata2 <- search.isc(start.year=2017, start.month=11, start.day=12,
                   end.year=2018, end.month=3, end.day=01,
                   searchshape="CIRC", 
                   lat.ctr=34.905, long.ctr=45.956,
                   radius=150, dist.units="km",
                   mag.min=3.5, mag.type='ML') 
  mycatalog2 <- catalog(mydata2)
  plot(mycatalog2)
  
# }
# NOT RUN {
# }