SAIG: Tools & Data

Small data sets

All files are in xdr-based system-independent Seismic Unix format

  bytes  filename
-------------------------------------
   88464   syn_cmp.su
  112200   data_with_noise.su
     420   wavelet_for_small_stack.su
     380   min_phase_wavelet.su
  666448   gom_cdp_nmo.su
   20800   small_stack.su
  207956   syn_cmp_mult.su
 1939000   Netherlands.su
69012144   prestack_section.su

Example:

julia> using PyPlot, Seismic
julia> download("http://seismic.physics.ualberta.ca/data/gom_cdp_nmo.su","gom_cdp_nmo.su");
julia> SegyToSeis("gom_cdp_nmo.su","gom_cdp_nmo",format="su",input_type="ieee",swap_bytes=true)
julia> d,h,ext=SeisRead("gom_cdp_nmo");
julia> SeisPlot(d,ext)

From a terminal you can now check the content of gom_cdp_nmo

msacchi@macbook:~$ more gom_cdp_nmo
        n1=1751
        n2=92
        n3=1
        n4=1
        n5=1
        o1=0.0
        o2=1.0
        o3=0.0
        o4=0.0
        o5=0.0
        d1=0.004
        d2=1.0
        d3=1.0
        d4=1.0
        d5=1.0
        label1="Time"
        label2="Trace Number"
        label3=""
        label4=""
        label5=""
        unit1="s"
        unit2="index"
        unit3=""
        unit4=""
        unit5=""
        title=""
        data_format="native_float"
        esize=4
        in="/Users/msacchi/gom_cdp_nmo@data@"
        headers="/Users/msacchi/gom_cdp_nmo@headers@"

The binary data is in gom_cdp_nmo@data@ and the headers are in gom_cdp_nmo@headers@

Marmousi P-wave velocity

julia> using PyPlot, Seismic
julia> download("http://seismic.physics.ualberta.ca/data/marmvel.bin","marmvel.bin");
julia> n1=751;n2=2301; 
julia> dx =4; dz = 4;
julia> f=open("marmvel.bin");
julia> v = read(f, Float32,n1*n2);
julia> SeisPlot(reshape(v,n1,n2),dx=dx,dy=dz)