测井(国外英文资料).doc

测井(国外英文资料) Spontaneous potential logging: Measure the potential produced by electrochemical action of the formation. The positive, negative and magnitude of the polarity of natural potential are consistent with the relation between mud filtrate resistivity Rmf and formation water resistivity Rw. Rmf is Rw, SP is almost flat; Rmf Rw SP negative anomaly; Rmf Rw, SP in the penetration layer shows a positive anomaly. Spontaneous potential logging Application of SP curve: dividing permeable stratum. To judge lithology and carry out stratigraphic correlation. Estimate the content of shale. Determine formation water resistivity. Determination of water flooded layer. Study on the sedimentary phase. Positive anomaly of natural potential When Rmf Rw, SP appears positive abnormality. Fresh water layer Rw is very large (shallow stratum) Salt water mud (relative to formation water resistivity) Spontaneous potential logging The natural potential curve has a good correspondence with the natural gamma ray and microelectrode curves. Baseline curves of natural potential curves appear in watered out layers Two, common resistivity logging (R4, R2.5) The common apparent resistivity log is a well logging method for studying the electric field distribution in various media. When measuring the first medium to pass into the current caused by the artificial electric field, resistivity, this field distribution depends on the surrounding medium. Therefore, as long as the measured electric field distribution characteristics of various medium can determine the resistivity of the medium. Application of apparent resistivity curve: 1. Dividing lithologic section. Seeking true resistivity of rock stratum. Rock porosity. Depth correction. Stratigraphic correlation. Electrode system logging 2.5 meters at the bottom of a casing resistivity gradient into the shielding tip, which corresponds to the depth of the casing shoe; if the casing is deep and may not log on the cusp of the shield, when availabl