5 March, 2008

Palaeo-age, depth-to-basement and bathymetry grids of the world's ocean basins from 140-1 Ma

Reference

Muller, R.D., Sdrolias, M., Gaina, C., Steinberger, B. and Heine, C., 2008, Science


age_depth_bath_${age}.xyadb             A simple ASCII file (long, lat, age, depth-to-basement, bathymetry).
                                        The age units are in millions of years with no scaling.
					The depth-to-basement and bathymetry are in meters with no scaling.
                                        The file spans longitudes from 0 E to
                                        360 E and latitudes from 90 N to -90 N.
                                        6 minute resolution, gridline-registered.

All files are compressed with bzip2. Use bunzip2 for unzipping of the
files.                                  

To load these files in ArcGIS you need to:
1.  Extract the data columns that you want to plot.  
2.  Convert this ASCII file into a netcdf grid using your preferred gridding software (e.g. GMT, GDAl, Matlab). 
3.  Import the grid into ArcGIS

The instructions on how to do this for GMT are as follows:
1.  gmtconvert filename -F0,1,2 > outputfile (note: this is to extract the age, change the -F option to plot bathymetry or depth2basement)
2.  xyz2grd outputfile -Goutputgrid -E -Rg -I0.1
3.  Import outputgrid into ArcGIS

Improvements:		We have included a model for the oceanic crust in the Bering Sea after the
			Science paper submission.
						An interpolation artifact off the east coast of India
						has been fixed (18 July, 2008)
                                        
Known Bugs:             Gridding artifacts exist around microplates (e.g.
Bauer microplate), along fracture zones (e.g. Central Atlantic) and in
areas with highly oblique spreading (e.g. South-West Indian Ridge).
                                        
Contribute:             If you would like your work to be included in the next
version of the agegrid, please send us an email.
                                        
Any questions, please email:            
                                        Dietmar Muller dietmar.muller@sydney.edu.au
                                        Maria Seton maria.seton@sydney.edu.au