Difference between revisions of "Dictionary:Static self-potential (SSP)"

From SEG Wiki
Jump to: navigation, search
(Prepared the page for translation)
(Marked this version for translation)
 
Line 3: Line 3:
 
</translate>
 
</translate>
 
{{lowercase}}
 
{{lowercase}}
<translate>{{#category_index:S|static self-potential (SSP)}}
+
<translate><!--T:1-->
 +
{{#category_index:S|static self-potential (SSP)}}
 
The maximum SP that would be recorded when the borehole logging sonde passes from within a very thick, porous, permeable, clean sand to a point that is well within a thick shale. The <b>electrochemical SSP</b> (the electrokinetic SP is often neglected) is approximately given by:  
 
The maximum SP that would be recorded when the borehole logging sonde passes from within a very thick, porous, permeable, clean sand to a point that is well within a thick shale. The <b>electrochemical SSP</b> (the electrokinetic SP is often neglected) is approximately given by:  
  
 +
<!--T:2-->
 
<center><math>SSP=-K log_{10} \frac{a_w}{a_{mf}}</math>,</center>
 
<center><math>SSP=-K log_{10} \frac{a_w}{a_{mf}}</math>,</center>
  
 +
<!--T:3-->
 
where ''a''<sub>''w''</sub> is the activity of the formation water and ''a''<sub>''mf''</sub> that of the mud filtrate. Because of the inverse relationship between activity and equivalent resistivity, this equation can be written:  
 
where ''a''<sub>''w''</sub> is the activity of the formation water and ''a''<sub>''mf''</sub> that of the mud filtrate. Because of the inverse relationship between activity and equivalent resistivity, this equation can be written:  
  
 +
<!--T:4-->
 
<center><math>SSP=-K log_{10} \frac{a_{mfe}}{a_{we}}</math>.</center>
 
<center><math>SSP=-K log_{10} \frac{a_{mfe}}{a_{we}}</math>.</center>
  
 +
<!--T:5-->
 
where ''R''<sub>''mfe''</sub>=equivalent mud filtrate resistivity, ''R''<sub>''we''</sub>= equivalent water resistivity. For NaCl muds that are not too saline, ''R''<sub>''mfe''</sub>=''R''<sub>''mf''</sub>; for other muds an activity correction should be made. In these equations <math display="inline">K=60+0.133 T</math> where ''T''=Fahrenheit temperature. See also [[Special:MyLanguage/Dictionary:SP|''SP'']] and [[Special:MyLanguage/Dictionary:pseudostatic_SP_(PSP)|''pseudostatic SP'']].
 
where ''R''<sub>''mfe''</sub>=equivalent mud filtrate resistivity, ''R''<sub>''we''</sub>= equivalent water resistivity. For NaCl muds that are not too saline, ''R''<sub>''mfe''</sub>=''R''<sub>''mf''</sub>; for other muds an activity correction should be made. In these equations <math display="inline">K=60+0.133 T</math> where ''T''=Fahrenheit temperature. See also [[Special:MyLanguage/Dictionary:SP|''SP'']] and [[Special:MyLanguage/Dictionary:pseudostatic_SP_(PSP)|''pseudostatic SP'']].
 
</translate>
 
</translate>

Latest revision as of 03:12, 27 November 2017

Other languages:
English • ‎español


The maximum SP that would be recorded when the borehole logging sonde passes from within a very thick, porous, permeable, clean sand to a point that is well within a thick shale. The electrochemical SSP (the electrokinetic SP is often neglected) is approximately given by:

,

where aw is the activity of the formation water and amf that of the mud filtrate. Because of the inverse relationship between activity and equivalent resistivity, this equation can be written:

.

where Rmfe=equivalent mud filtrate resistivity, Rwe= equivalent water resistivity. For NaCl muds that are not too saline, Rmfe=Rmf; for other muds an activity correction should be made. In these equations where T=Fahrenheit temperature. See also SP and pseudostatic SP.