色谱相关系数和随钻电性参数实时评价地层流体方法

Real-time evaluation of formation fluid by correlation coefficient of chromatography and electrical parameters while drilling

为了充分挖掘气测和随钻测井数据在地层流体评价中的价值,进一步提高评价的精确度,给出了一种基于轻烃色谱图(轻烃取C_1-C_8)和随钻电性分析的油气水评价方法。通过类比信号处理领域的相关函数,将色谱信号看作连续时间内的轻烃组成分布输出,计算连续井深上的色谱互相关函数,并提取色谱组成中能有效反映油气水变化的3种特征参数(气指数G、油指数P以及水指数W);当储集层流体性质发生改变时,相关函数和3种特征参数亦发生相应改变,建立其变化趋势和方向的区域标准,实时指导待测储集层流体性质的识别。该方法能够在一定程度上弥补常规色谱在含水储集层的识别以及随钻电性参数在含水气层评价上的不足,通过实时在线对复杂的油气水组成进行解释评价,取得了很好的效果。

In order to fully tap value of gas logging and LWD data in formation fluid evaluation and improve the accuracy of evaluation,a method for evaluating oil,gas and water based on light hydrocarbon chromatogram(C_1-C_8)and electrical analysis while drilling was given.Through analog signal processing correlation function in the field,the chromatographic signal is regarded as the distribution output of the light hydrocarbon composition in continuous time,the chromatographic cross-correlation function of the continuous well depth is calculated,and three characteristic parameters which can effectively reflect the changes of oil,gas and water(gas index G,oil index P and water index W)were extracted.When the fluid properties of the reservoirs change,the correlation function and three characteristic parameters also change correspondingly,the regional standards for change trends and directions were established and they can real-time guide the identification of fluid properties of reservoirs to be tested.To a certain extent,the method can make up the deficiency of the identification of conventional chromatography in aqueous reservoir and the evaluation of electrical parameters while drilling water-bearing gas layer.Throuth real-time and on-line interpretation and evaluation of complex oil,gas and water composition in real time,better effects have been obtained.