Barium (Ba) 



It is the extremely weak solubility of barium that regulates the content of 

 barium in connate waters. But the concentration can be considerably increased 

 by the chlorine and sodium content of the water, and by a weak concentration or 

 absence of the SO4 ion. 



Manganese (Mn) 



Very few determinations of manganese have been made on connate waters. 

 In waters where it has been determined it was found to be present in very 

 minute quantities. 



Boron (B) 



Some concentrations of boron found in the ordinary vadose waters of the 

 sedimentary formations are high compared to the very small concentrations 

 generally found in the waters from crystalline rocks. Boron occurs in the boric 

 acid or borate state. 



Nickel, Cobalt, Arsenic (Ni, Co, As) 



It is known that these metals exist in petroleum, but only recently their 

 presence in connate waters has been determined. 



SUMMARY COMMENTS Water analyses have proved very valuable not 



only in subsurface studies with respect to 

 underground water migration, but also in electric-log interpretation and in 

 well remedial and recompletion operations. 



The value and application of water analyses are greatly improved if care 

 is exercised in taking the samples and some method of graphically presenting 

 the individual water information is used. A graphical presentation can indicate 

 clearly that waters from various formations, even though very similar, can be 

 distinguished easily from each other. Changing scales on the diagrams to ac- 

 centuate a certain component may be the key to identification; however, scale 

 changes must be done with caution to avoid confusion when comparing or 

 correlating. 



For the pattern system to be effective, a laboratory analysis of at least six 

 chemical components is necessary. If the analyses are to be used for subsurface 

 studies, as complete an analysis as possible should be made because the presence 

 or concentration of each component has significance. 



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