Topic:
Underflows and overflows when loading seismic.

Description:
What is the meaning of underflows and overflows when loading seismic.

 *I* 1-74_stk_agc_c                                                             
 *I* ** End cdp 372.                                                            
 *I* ** ACCEPTED 372 Traces.                                                    
 *Warn* # underflows: 6991. Worst case exp: 0.                                  
 *Warn* # overflows: 0. Worst case exp: 0.                                      
 *I* ***  

Solution:
Generally overflow or underflow is the data being converted to internal 
floating point and is nothing to worry about. 

Other possibilities, especially if the data will not load:

1. There may be spike in a trace somewhere. 

Options: 
a. Stop loading when you get the errors and look in seismic report to see if
the min/max range of amplitudes are correct.

b. Do a more complete seg-y dump. If there is a spike, you may need to get a
new tape from vendor without spikes in the data.  

c. Skip the bad data while loading.  

d. If amplitude are more that 10^15 and those values are correct, not a
contractor error, then use a scalar in the loading definition to
lower them.

2. You may have a bad tape. See if you can tcopy the file to disk and load it. 
Otherwise, call contractor for a new tape.




Last Modified on: 10-FEB-99