RSEIS (version 2.4-5)

JSAC.seis: JSAC.seis

Description

Read SEGY/SAC format binary data

Usage

JSAC.seis(fnames, Iendian = 1 , HEADONLY=FALSE, BIGLONG=TRUE, PLOT = FALSE)
JSEGY.seis(fnames, Iendian = 1 , HEADONLY=FALSE, BIGLONG=TRUE, PLOT = FALSE)

Arguments

fnames

vector of file names to be extracted and converted.

Iendian

Endian-ness of the data: 1,2,3: "little", "big", "swap". Default = 1 (little)

HEADONLY

logical, TRUE= header information only

BIGLONG

logical, TRUE=long=8 bytes

PLOT

logical, whether to plot the data after reading in

Value

• List containing the seismic data and header information. Each trace consists of a list with:
• fn
  original file name
• sta
  station name
• comp
  compnent
• dt
  delta t in seconds
• DATTIM
  time list
• yr
  year
• jd
  julian day
• mo
  month
• dom
  day of month
• hr
  hour
• mi
  minute
• sec
  sec
• msec
  milliseconds
• dt
  delta t in seconds
• t1
  time start of trace
• t2
  time end of trace
• off
  off-set
• N
  number of points in trace
• units
  units
• amp
  vector of trace values
• HEAD
  Full header as a data-frame of values (mixture of float and character strings)
• N
  Number of samples in trace
• units
  Units of samples, possibly: counts, volts, s, m/s, Pa, etc
• IO
  list: kind, Iendian, BIGLONG flags for I/O

Details

Uses readBin to extract data in SAC format. user must know what kind of machine the data was created on for I/O purposes.

For SEGY data the program is the same, although SEGY data does not have the problem of the BIGLONG so that is ignored.

For either code, a full header is returned, although the header for each format may be different.

See Also

Mine.seis

Examples

####  this will return a list of traces
Lname = list.files(path='/data/wadati/bourbon/LaurelCanNC/R005.01' , pattern="08.005.01.41.23.9024", full.names=TRUE)

S1  = JSAC.seis(Lname, Iendian = 1, PLOT = FALSE)


#####################   from a data base example: this will return one
#####                    trace header
f1 = DB$fn[200]

j1 = JSAC.seis(f1, Iendian=1, HEADONLY=TRUE , BIGLONG=FALSE, PLOT=FALSE)

print( j1[[1]]$HEAD )


#############   example for SEGY data: one SEGY  header

dir = "/data/wadati/soju/SEISMIC_DATA/Reventador2005/rev05/SEGY/R251.01"
lf = list.files(path=dir, pat="05.251", full.names=TRUE)
f1 = lf[1]
j1 = JSEGY.seis(f1, Iendian=1, HEADONLY=TRUE , BIGLONG=FALSE, PLOT=FALSE)


print( j1[[1]]$HEAD )