914 EXPLORATION GEOPHYSICS 



II. Briefing (Some of this responsibility may be assumed by geophysical department 

 or coordinator if such facilities are available.) 

 When the most promising geophysical method has been decided upon and con- 

 tracted for, arrange a conference with supervisor and party chief to : 



1. Select headquarters of crew where minimum time will be lost in driving to and 

 from work area. However, in selecting headquarters, consider morale of crew. 

 Somewhat longer driving distance may be repaid in higher production if 

 morale of crew is high. 



2. Furnish all literature on area in which prospects are located. Brief the geo- 

 physicists on regional geology and geology of local prospects. Advise them 

 of probable unconformities, intervals of convergence or divergence, facies 

 changes, suspected faults. Be certain the man actually doing interpretation 

 knows these things. Give him your theories. 



3. Provide maps showing location of prospect areas, location of wells critical to 

 the prospects and the geology of the area. Furnish electric, radioactive and/or 

 sample logs with correlations of wells to which they are expected to tie. Grade 

 and qualify all well data as to accuracy and reliability. If accurate correlations 

 cannot be furnished, explain why. 



4. Decide on method of shooting to be employed, whether refraction or reflection, 

 correlation or continuous line, dip shooting, three dimensional control. Con- 

 sider possibility of air shooting. 



5. Lay out preliminary lines, making full use of the geophysicists' suggestions 

 and recommendations. Lay out lines so that areas of possible reverse dip can 

 be quickly confirmed or denied. Lines generally should be laid out normal to 

 the strike. Consider the road network, but avoid roads in areas in which much 

 work has been done by others. This may not be too important in difficult areas, 

 but it may increase the problems of interpretation. 



6. Furnish the geophysical crew with road maps, topographic maps and aerial 

 photos of prospect areas. 



7. Arrange to go into the field, if necessary, to determine what portions of pros- 

 pects can be held back for inclement weather or season. 



8. Advise the geophysicist the desired formations or zones from which to obtain 

 reflections or refractions, and why. Certain important events may be brought 

 out at the expense of less important ones. Shoot two or more records. 



9. Check shot hole drilling difficulties. Often two or more drills may be econom- 

 ically advantageous. 



10. Educate the field parties in the proper safe operating practices (truck driving, 

 drilling, dynamite storage and transporting, shot-hole loading and firing, etc.). 

 Assign an assistant to party chief to observe that all regulations are being 

 followed. Party chief will be held responsible for safety of crew and 

 equipment. 



III. Execution (Part of responsibility can be assumed by geophysical department or 

 coordinator if such facilities are available.) 



1. Be certain that work assignments are sufficient, with careful planning to secure 

 maximum efficiency of crew. Consult continuously with supervisor and party 

 chief on their suggestions for assignments. 



2. Maintain frequent contact with crew during work by telephone and trips to 

 field. 



3. Obtain progress maps for all horizons weekly. Plot your own progress map. 



4. Obtain a weekly progress report, summarizing the work of all units of crew 

 to be certain that each is being utilized to the best economic advantage. 



5. Check costs continuously to see if an increase or decrease in personnel will 

 reduce costs per unit area. Check particularly costs of items chargeable to 

 your client. 



