EXHIBIT 21

SUBSIDIARIES OF THE REGISTRANT

The following is a list of all subsidiaries, wholly owned except where noted, owned by the Registrant or one or more of its other subsidiaries at July 31,
2004:

|Corporate Name of Subsidiary                                |  | State or Country of Incorporation
|----------------------------------------------------------- |  | ---------------------------------
|Veritas DGC Asia Pacific Ltd.                               |  | Delaware, U.S.A.                 
|Veritas DGC Land Inc                                        |  | Delaware, U.S.A.                 
|Veritas Geophysical Corporation                             |  | Delaware, U.S.A.                 
|Viking Maritime Inc.                                        |  | Delaware, U.S.A.                 
|Euroseis, Inc                                               |  | Delaware, U.S.A.                 
|Alitheia Resources Inc.                                     |  | Delaware, U.S.A.                 
|Veritas Geophysical (Mexico) L.L.C                          |  | Delaware, U.S.A.                 
|Veritas Investments Inc.                                    |  | Delaware, U.S.A.                 
|Veritas Energy Services Inc                                 |  | Alberta, Canada                  
|Veritas Energy Services Partnership                         |  | Alberta, Canada                  
|Veri-Illuq Geophysical Ltd. (49% owned)                     |  | Alberta, Canada                  
|Veritas MacKenzie Delta Ltd.                                |  | Alberta, Canada                  
|Time Seismic Exchange Ltd.                                  |  | Alberta, Canada                  
|Time Seismic Leasing Ltd.                                   |  | Alberta, Canada                  
|Hampson Russell GP Inc.                                     |  | Alberta, Canada                  
|Hampson Russell Limited Partnership                         |  | Alberta, Canada                  
|Veritas Geophysical (Canada) Corporation                    |  | Nova Scotia, Canada              
|Yamoria Geophysical, Ltd. (49% owned)                       |  | NW Territories, Canada           
|Veritas DGC Australia Pty. Ltd.                             |  | Australia                        
|Guardian Data Seismic Pty Limited                           |  | New South Wales, Australia       
|Veritas do Brasil Ltda.                                     |  | Brazil                           
|Veritas DGC (B) Sdn. Bhd.                                   |  | Brunei                           
|Veritas Geophysical I                                       |  | Cayman Islands                   
|Veritas Geophysical II                                      |  | Cayman Islands                   
|Veritas Geophysical III                                     |  | Cayman Islands                   
|Veritas Geophysical IV                                      |  | Cayman Islands                   
|VGS Holdings (Cayman) Inc.                                  |  | Cayman Islands                   
|VGS Inc.                                                    |  | Cayman Islands                   
|VTS Offshore I, LLC                                         |  | Cayman Islands                   
|VTS Offshore II, LLC                                        |  | Cayman Islands                   
|Exploraciones Geofisicas Veritas Geophysical Chile Limitada |  | Chile                            
|Veritas Geophysical (France) SARL                           |  | France                           
|Veritas DGC Land Guatemala S.A.                             |  | Guatemala                        
|HOT Engineering KMSZ KFT                                    |  | Hungary                          
|HOT Engineering Gmbh                                        |  | Austria                          
|P.T. Veritas DGC Mega Pratama (80% owned)                   |  | Indonesia                        
|Veritas DGC (Malaysia) Sdn. Bhd. (70% owned)                |  | Malaysia                         
|Veritas DGC (Mexico) S. de R.L. de C.V.                     |  | Mexico                           
|Veritas Servicios Geofisicos S. de R.L. de C.V.             |  | Mexico                           
|Veritas Servicios Technicos S. de R.L. de C.V.              |  | Mexico                           
|Veritas Energy Services (Nigeria) Limited                   |  | Nigeria                          
|Digicon (Nigeria) Ltd. (60% owned)                          |  | Nigeria                          
|Veritas Geophysical (Nigeria) Limited (60% owned)           |  | Nigeria                          
|Veritas Geophysical Services (Norway) AS                    |  | Norway                           
|Veritas DGC Singapore Pte. Ltd.                             |  | Singapore                        
|Veritas DGC Limited                                         |  | United Kingdom                   
|Veritas Geoservices Ltd. SA                                 |  | Venezuela                        
|Digicon de Venezuela, C.A                                   |  | Venezuela                        

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