JGET.seis {RSEIS}R Documentation

Reads various seismic file formats

Description

This fuction calls c-routines to read in ‘segy’, ‘sac’.

Usage

JGET.seis(fnames, kind = 1, Iendian=1, BIGLONG=FALSE , HEADONLY=FALSE,  PLOT = FALSE)
getseisinfo(fnames, kind = 1)

Arguments

fnames list of file names.
kind an integer 1, 2, 3; 0=R(DAT) , 1 = segy, 2 = sac, 3 = AH.
Iendian Endian-ness of the data: 1,2,3: "little", "big", "swap". Default = 1 (little)
BIGLONG logical, TRUE=long=8 bytes
HEADONLY logical, TRUE= header information only; not seismic trace will be returned (runs a little faster).
PLOT logical, for if the traces should be plotted. This is interactive and can be shut off for large data sets.

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.

If data was created on a little endian machine but is being read on big endian machine, need to call the endian "swap" for swapping.

If data was created on a machine with LONG=4 bytes, be sure to call the program with BIGLONG=FALSE.

See examples below for different cases.

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

Note

OLDER:

getseisinfo gets only the header information from the trace. Information in the file names is ignored, so be sure to modify headers prior to using this method of extracting meta-data. (Or modify the meta data from the file names after reading in the data.)

For SEGY files, in LINUX-UNIX, use: rename, segymod (PASSCAL) to modify the headers

JGET.seis extracts digital seismic data from binary files stored in the file system. The program uses readBin for I/O and passes data back to R. Currently SAC, SEGY formats are installed but it is easy to extend. AH format is available for LINUX systems, but there were problems compiling in WINDOWS and MACOS so this feature was removed. A filter for mseed format is currently being developed.

getseisinfo is an older (superceded) C-coded version to get the headers.

Author(s)

Jonathan M. Lees <jonathan.lees@unc.edu>

See Also

JSAC.seis , Mine.seis

Examples

  
## Not run: 

Lname = list.files(path='/data/wadati/bourbon/LaurelCanNC/R005.01' , pattern="08.005.01.41.23.9024", full.names=TRUE)

S1  = JGET.seis(Lname, kind = 1, PLOT = FALSE)

###   for data created on UNIX (SUN) but read on linux:

S1  = JGET.seis(Lname, kind = 1, Iendian="swap", BIGLONG=FALSE, PLOT = FALSE)

###   for data created on linux (32 bit)  but read on linux 64 bit:

S1  = JGET.seis(Lname, kind = 1, Iendian="little", BIGLONG=FALSE, PLOT = FALSE)

###   for SEGY data created on linux (64 bit)  but read on linux 32 bit:

S1  = JGET.seis(Lname, kind = 1, Iendian="little", BIGLONG=TRUE, PLOT = FALSE)

###   for SAC data created on MAC-OS (64 bit)  but read on linux 32 bit:

S1  = JGET.seis(Lname, kind = 2, Iendian="swap", BIGLONG=TRUE, PLOT = FALSE)



## End(Not run)


[Package RSEIS version 2.3-3 Index]