×

Method and apparatus for producing a new output record medium illustrating a quantitative description in the volume dimension of mud filtrate invasion into permeable zones of a formation in a wellbore

  • US 5,379,216 A
  • Filed: 05/27/1992
  • Issued: 01/03/1995
  • Est. Priority Date: 05/27/1992
  • Status: Expired due to Term
First Claim
Patent Images

1. A system responsive to a set of invasion parameters associated with each unit of depth in a wellbore for generating an output record medium, comprising:

  • first means responsive to the set of invasion parameters associated with said each unit of depth in said wellbore for determining a corresponding volume of mud filtrate which has invaded into permeable zones of a formation traversed by said wellbore for a given thickness at said each unit of depth in said wellbore,said permeable zones of formation at said each depth in said wellbore including a flushed zone, an uninvaded zone, and a transition zone interposed between said flushed zone and said uninvaded zoned,said invasion parameters including a resistivity of the flushed zone (Rxo), a radius (r1) measured from a wall of said wellbore to an outer radial extremity of said flushed zone, and a radius (r2) measured from a wall of said wellbore to an inner radial extremity of said uninvaded zone,said first means determining said volume of mud filtrate invasion into said flushed zone and said transition zone of said formation for a given thickness at said each unit of depth in said wellbore by using the following equation;

    
    
    space="preserve" listing-type="equation">Vmf=3.1416 . . . /3[(Rmf/Rxo).sup.1/n ][r.sub.1.sup.2 +(r.sub.1)(r.sub.2)+r.sub.2.sup.2 -3r.sub.b.sup.2 ],where Vmf is the volume of mud filtrate, Rmf is the resistivity of said mud filtrate, and rb is the radius of said wellbore; and

    output record generating means responsive to the volume of mud filtrate invasion into said permeable zones of said formation for said given thickness at said each unit of depth in said wellbore determined by said first means for generating an output record medium illustrating said volume of mud filtrate invasion into said permeable zones of said formation at said each unit of depth in the wellbore.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×