This is a log of measurements along a well bore (a well-log). You could find this abbreviation RND in your log evaluation software or any (ASCII) log files provided by the logging company. The official name for this log is 'Real-Time CNP (Dolomite Matrix)'. The business value of this log is often deamed high.

Use this log to investigate the porosity derived from a neutron logging measurement, assuming that the rock matrix material is dolomite.

So basically this is a measure of the porosity as measured with an neutron logging device.

In general this log thus reflects units of the apparent porosity. In other words, the initial estimate of porosity, normally from logs, not corrected for the (often large) effects of clays, gas, etc. Such estimates should only be used for qualitative interpretation of clean, gas-free intervals. At a more general level these values are measures of the volume fraction. This can be explained as being the ratio of the volumes occupied by two components, or by one component to the total volume of the system.

This log usually has the unit 'Porosity'. This is the pore volume per unit gross volume. Porosity is determined from measurements on cores or interpreted from logs.

Data for this log is produced by a tool that uses a neutron logging technique and can be used to investigate the porosity of the formation. Similar logs are listed below:

• Neutron Porosity (NEU)
• Smoothed CNP (Sandstone Matrix-Fixed Hole Size) (SPSF)
• Smoothed Neutron Porosity (LS, SS, or DOL) With Subsequent Formation Salinity, Temperature, and Pressure Corrections Applied (NUCP)
• Density Porosity Limestone, Memory (DPLM)
• Smoothed Near Detector ONLY Porosity (Sandstone Matrix-Caliper Corrected) (SNSC)
• Enhanced Thermal Neutron Porosity in Selected Lithology (NPL)
• Smoothed CNP (Dolomite Matrix-Caliper Corrected) (SPDC)
• Thermal Neutron Porosity (TNPA)
• APS Near/Far Corrected Limestone Porosity (FPLC)
• Smoothed CNP (Limestone Matrix-Fixed Hole Size) (SPLF)