The two gas curves, total gas, and heavier hydrocarbons are recorded by 

 a strip-chart recorder (fig. 17-6). The drilling rate may be recorded on the 

 same chart by an electrical connection with a geolograph or similar instrument. 

 Shows may be correlated with their proper depth by making a suitable allow- 

 ance for lag time. Thus, the interested party has at all times a permanent up- 

 to-date record of the most important factor in mud logging — indications of 

 hydrocarbons in the drilling mud corrected to the depth from which they came. 



BIBLIOGRAPHY 



Pixler, B. 0., 1946, Some recent developments in mud analysis logging: Petroleum Tech- 

 nology, Tech. Pub. 2026, v. 9, no. 3, p. 1-13. 



Wilson, R. W., 1949, Methods and application of mud analysis and cuttings analysis well 

 logging: Paper presented at Symposium on Subsurface Logging Techniques, Univ. 

 Oklahoma, April. 



, and Short, A. W., 1954, Mud logging in the Eocene Wilcox formation: 



Gulf Coast Assoc, of Geol. Soc. Trans. (Nov.) 



366 



