Changes

{| class = "wikitable"

{| class = "wikitable"

|-

|-

! Step

! Step || Action

! Action

|-

|-

| 1

| 1 || Use the table below to determine how to enter a neutron porosity value.

| Use the table below to determine how to enter a neutron porosity value.

{| class = "wikitable"

 

*  <table-wrap id="ch09utbl24a" position="float"> <table frame="hsides"> <colgroup> <col align="left"></col> <col align="left"></col> </colgroup> <thead> <tr> <th align="left"> If… </th> <th align="left"> Then… </th> </tr> </thead> <tbody> <tr> <td align="left"> Neutron porosity is in limestone units Enter the chart along the x-axis with neutron porosity. Project up to density porosity. </td></tr> <tr> Neutron porosity is in sandstone or dolomite units Enter the chart on the sandstone or dolomite line. Project up or down to a density value. </tr> </tbody> </table> </table-wrap>

 

|-

|-

| <th align="left"> If…</th>

! If… || Then…  

| <th align="left"> Then…</th>

|-

|-

| Neutron porosity is in limestone units

| Neutron porosity is in limestone units || Enter the chart along the x-axis with neutron porosity. Project up to density porosity.  

| Enter the chart along the x-axis with neutron porosity. Project up to density porosity.

|-

|-

| Neutron porosity is in sandstone or dolomite units

| Neutron porosity is in sandstone or dolomite units || Enter the chart on the sandstone or dolomite line. Project up or down to a density value.

| Enter the chart on the sandstone or dolomite line. Project up or down to a density value.

|}

|}

 

<tr><td align="center" valign="top">2</td><td align="left">Use the table below to determine how to enter a density porosity value

| 2 || Use the table below to determine how to enter a density porosity value

 

 

{| class = "wikitable"

{| class = "wikitable"

|-

|-

! If…

! If… || Then…  

! Then…

|-

|-

| Density log porosity is in sandstone, limestone or dolomite units

| Density log porosity is in sandstone, limestone or dolomite units || Find the density log percent porosity value on the diagonal line that matches the lithologic units recorded on the log (i.e., use the sandstone line if the log was recorded in sandstone units). Move left or right to intercept the neutron projection.

| Find the density log percent porosity value on the diagonal line that matches the lithologic units recorded on the log (i.e., use the sandstone line if the log was recorded in sandstone units). Move left or right to intercept the neutron projection.

|-

|-

| Density log scale is bulk density

| Density log scale is bulk density || Enter the y-axis with the log bulk density value and intercept the neutron projection.

| Enter the y-axis with the log bulk density value and intercept the neutron projection.

|}

|}

 

</td></tr><tr><td align="center" valign="top">3</td><td align="left">Use the table below to determine formation lithology and porosity.

| 3 || Use the table below to determine formation lithology and porosity.

 

 

{| class = "wikitable"

{| class = "wikitable"

|-

|-

! If…

! If… || Then…

|-

|-

| Point falls on a diagonal line

| Point falls on a diagonal line || The point defines the lithology of the formation by which line it falls on and the porosity is the value marked on the line at that point.

| The point defines the lithology of the formation by which line it falls on and the porosity is the value marked on the line at that point.

|-

|-

| Point falls away from appropriate diagonal line

| Point falls away from appropriate diagonal line|| Move down and to the right parallel to the nearest dashed line until a diagonal line is intersected. Read the value for porosity at that point. The lithology is a combination of the lithologies of the lines on either side of the point of intersection. Gas is present if the original point is northwest of the appropriate diagonal lithology line.

| Move down and to the right parallel to the nearest dashed line until a diagonal line is intersected. Read the value for porosity at that point. The lithology is a combination of the lithologies of the lines on either side of the point of intersection. Gas is present if the original point is northwest of the appropriate diagonal lithology line.

|}

|}

===Example density–neutron crossplot===

===Example density–neutron crossplot===