SEG-Y Reader Limitations

The SEG-Y Reader can import most files that loosely adhere to the SEG-Y standard. Some features of the revised standard are also supported, such as Inline/Crossline trace header fields and 3D surveys, in general. It does not support extended text headers.

The SEG-Y Reader is capable of processing disk files on the order of tens of Gb.  However, there are some size limitations.

Input SEG-Y Size Limit

• Maximum number of traces in a 2D or 3D SEG-Y file is 2^32, or about 4 billion traces.

2D Image Export Size Limit

• GM-SYS Profile Modelling can have problems importing backdrop images larger than about 25 Mb. This limit is dependent on available system resources. In general, images should be kept below the default limit of 25 Mb.

Voxel export Size Limits

1. There is a soft limit of 512 Mb for exported voxels; equivalent to 512^3 voxel cells, or about 134 Million cells. There is no specific limitation on any particular dimension NX, NY, or NZ, so long as NX x NY x NZ < 512^3.

2. Beyond this limit, processing time will increase dramatically, from tens of minutes to several hours. You will be warned that you have exceeded this limit and given the option of continuing with the export or of subsampling the survey to reduce the size of the output voxel. Note that a read-only field in is continuously updated with the number of cells in the volume, so you can adjust the voxel dimensions appropriately.

3. There is a hard limit on the voxel size of 1500^3 cells, or 3.3 billion cells. You will be warned if your settings exceed this limit and allowed to subsample the survey. This limitation only applies to voxel export and will not prevent you from exporting the survey to a Geosoft Database (.gdb).