[GRASSLIST:1434] import .bil DEM file (cascadia.bil)

[Torge Schuemann]

Hi,

for quite a while I am trying to import a *.bil file into GRASS 5.0.1 by 
using various modules (r.in.bin and r.in.gdal).
I am not familliar with the *.bil format, but the archive "cascdem.tar.gz" 
I downloaded from http://geopubs.wr.usgs.gov/open-file/of99-369/ includes 
some meta data which I applied when using the import modules.

However, so far I haven't been lucky although I think I more or less tried 
every possible combination of the parameters given below.

As info for the data set itself: It contains a 250-meter digital elevation 
model (DEM) for Cascadia (latitude 39N - 53N, longitude 116W - 133W), a 
region that encompasses the Cascade volcanic arc, the Cascadia subduction 
zone, and the Juan de Fuca Ridge system offshore Washington (USA) and 
British Columbia (Canada).

Any help is appreciated, thank you all!

Cheers, Torge

Here below I copied the available information which is included in the tar 
archive.
***** cascadia.blw: *****
                  250.00000000000000
                    0.00000000000000
                    0.00000000000000
                 -250.00000000000000
              -737919.06250000000000
              1710215.28906250000000

***** cascadia.hdr: *****
BYTEORDER      M
LAYOUT       BIL
NROWS         6435
NCOLS         5951
NBANDS        1
NBITS         16
BANDROWBYTES         11902
TOTALROWBYTES        11902
BANDGAPBYTES         0

***** cascadia.prj *****
Projection    LAMBERT
Zunits        NO
Units         METERS
Spheroid      CLARKE1866
Xshift        0.0000000000
Yshift        0.0000000000
Parameters
  41 30  0.000 /* 1st standard parallel
  50 30  0.000 /* 2nd standard parallel
-124 30  0.000 /* central meridian
  38  0  0.000 /* latitude of projection's origin
0.00000 /* false easting (meters)
0.00000 /* false northing (meters)

***** cascadia.stx *****
1 5147 14378 9371.3 2076.8

***** excerpts from README.txt *****
This report contains a 250-meter digital elevation model (DEM) for Cascadia
(latitude 39N - 53N, longitude 116W - 133W), a region that encompasses the
Cascade volcanic arc, the Cascadia subduction zone, and the Juan de Fuca
Ridge system. The DEM is distributed as file cascdem.tar.gz  (39 MB; 78MB
uncompressed).

The DEM contains elevation values in integer meters, at regularly-spaced
points in a Lambert conformal conic projection with standard parallels at
latitudes 41.5N and 50.5N, and a central longitude of 124.5W (the
"Cascadia" projection.).

To ease data transfer for the widest possible range of users, the DEM is
distributed as a BIL (Band Interleave by Line) file, produced with the ARC
GRIDIMAGE command. For grids (the ARC term for a DEM in the form of a
regular array of height values), such files are more compact than ARC
export (.e00) files and USGS DEM-format files, and are much faster to
create and import. They can also be read by many applications other than
ARC. cascadia.bil is such a file of binary integers. Elevations are stored
in cascadia.bil as unsigned positive 2-byte binary integers, in Motorola
byte-order (default for Sun hardware), with an offset of 10000. That is,
203 meters is stored as 10203 meters, and values less than 10000 represent
negative elevations. Values of 0 in cascadia.bil represent no data. Values
are given by row, west to east, starting at the north edge of the region.

To convert CASCADIA files to an ARC grid

Assemble the cascadia.* files (.bil, .blw, .hdr, prj; .stx is not
necessary) in one directory. Make this your workspace.

      Arc: imagegrid cascadia casc1
      Arc: grid
      Grid: casc2 = con(casc1 <> 0, casc1 - 10000)
      Grid: &sys cp cascadia.prj casc2/prj.adf

If you DESCRIBE casc2 in ARC, you should get

      Description of Grid CASC2

      Cell Size = 250.000 Data Type: Integer
      Number of Rows = 6435 Number of Values = 8555
      Number of Columns = 5951 Attribute Data (bytes) = 8

      BOUNDARY STATISTICS

      Xmin = -738044.062 Minimum Value = -4853.000rs)
      0.00000

      Xmax = 749705.938 Maximum Value = 4378.000
      Ymin = 101590.289 Mean = -628.692
      Ymax = 1710340.289 Standard Deviation = 2076.818

                           COORDINATE SYSTEM DESCRIPTION

      Projection              LAMBERT
      Zunits                  UNKNOWN
      Units                    METERS             Spheroid
      CLARKE1866
      Parameters:
      1st standard parallel                                   41 30
      0.000
      2nd standard parallel                                   50 30
      0.000
      central meridian                                       -124 30
      0.00
      latitude of projection's origin                         38  0
      0.000
      false easting (meters)
      0.00000
      false northing (meters)
      0.00000