Drilling-time logs, 462 

 application, 462 

 geolograph, 468 

 method of preparing, 468 

 plotting, 471 

 Electric logging, 364 

 application of, 379 

 resistivity, 376 

 spontaneous potential, 364 

 Electric logs, 345 

 Electrical prospecting, 1110 

 controlled currents, 1113 

 natural earth currents, 1112 

 Electric pilot, 676 

 equipment, 677 

 in permeability surveys, 681 

 in selective acidizing, 679 

 in water locating, 684 

 Electron microscope, 202 



description, 203 

 Electron-microscope analysis, 202 

 bed identification, 205 

 correlation of clays, 207 

 correlation, geologic 



applications in, 202 

 correlation, long-range, 208 

 correlation, possible uses in, 205 

 crude oil, 208 

 paleontologic studies, 210 

 specimen mounting, 205 

 Facies, 22 

 definition, 24 

 examples of ancient facies 



changes, 30 

 examples of modern facies 

 changes, 30 

 Faults, 51 



criteria for recognition of, 52 

 definition, 51 

 geologic symbols, 160 

 gravity fault, 51 

 subsurface recognition of, 52 

 thrust fault, 51 

 Feldspars, 196 



identification of, 196 

 Fish scales, 113 

 Fluorescence exploration, 325 

 Fluoroanalysis in petroleum 

 exploration, 320 

 fluorescence exploration, 325 

 fluoroescence microscopy, 325 

 fluoroadsorption analysis, 324 

 fluorographic exploration, 327 

 fluorography, 324 

 fluorologging, 326 

 fluorometry, 323 

 methods of, 323 

 quenching analysis, 325 

 Fluorochemistry of petroleum, 321 

 Fluorographic exploration, 327 

 Fluorolog, 328 



Fluorolog — Cont. 



section of, 328 

 Fluorologging, 326 

 Folds, 161 



geologic symbols, 161 

 Foliation and cleavage, 162 



map symbols, 162 

 Foraminifera, 86 

 Formation testing, 731 



applications, 739 



equipment, 733 



pressure-recording-device chart, 745 



pressure-recording devices, 744 



procedure, 732 



types of testing packers, 737 

 Geochemical methods, 760 



analytical techniques, 764 



correction factors, 768 



future of, 772 



historical development, 760 



interpretations, 769 



results, 769 



theory, 761 

 Geologic cross sections, 884 



block diagram, 890 



directional-drilling, 886 



isometric construction in stratigraphic 

 compilation, 889 



iscmetric projection, 888 



outcrop area and subsurface distribu- 

 tion of Wilcox group, 892 



relative permeabilities, 887 



stratigraphic section, 885 



structural and stratigraphic condi- 

 tions of oil field, 891 

 Geolograph, 468 

 Geophysics, subsurface methods as 



applied in, 1038 



cost of geophysical surveys, 1042 



electrical prospecting, 1110 



geophysical exploration, 1039 



gravitational prospecting, 1060 



magnetic prospecting, 1042 



planning geophysical program, 1041 



seismic prospecting, 1084 



statistics, 1039 

 Grain roundness, 135 

 Graphic representations, 856 



block diagrams, use of, 878 



busk method, 874 



colored well-log symbols, 856 



columnar subsurface sections, 872 



compilation chart, 866 



complex faulting and divisions of 

 sand series and groups with re- 

 lation to geologic time divisions, 868 



complex faulting below major 

 unconformity, 876 



cores, drill-stem tests, production 

 tests, and production histories 

 of wells recorded on structure- 



