热中子衰减时间测井(TDT)是脉冲中子俘获测井的一种,它测量地层的热中子俘获性质——热中子衰减时间和宏观俘获截面。在一定地层水矿化度的情况下,这些测量值对于区分油(气)层和水层是很有用的。热中子衰减时间测井最主要的用途是在套管井里探测油气,确定地层含水饱和度的变化。因此,它对于解决油井生产中的问题和监测储集层动态具有重要的意义。基本原理 The thermal neutron decay time log (TDT) is a type of pulsed neutron capture log that measures the thermal neutron capture properties of the formation - the thermal neutron decay time and the macroscopic capture section. With certain formation water salinity, these measurements are useful for distinguishing between oil and gas layers. The main use of thermal neutron decay time logging is to detect oil and gas in cased wells and determine the change in the water saturation of the formation. Therefore, it is of great significance for solving the problems in oil well production and monitoring the reservoir dynamics. Fundamental